A Geological Journey KHAO YAI National park

A GEOLOGICAL JOURNEY KHAO YAI NATIONAL PARK

THE WONDER OF THE WORLD HERITAGE

A GEOLOGICAL JOURNEY KHAO YAI NATIONAL PARK THE WONDER OF THE WORLD HERITAGE

“Khao Yai National Park” has long

been visited by many visitors who left nothing behind but their foot steps. Each visitor has different experience and impression after each visit. One thing that has always been the same, from the time when it was the mysterious “Dong Phaya Yen” forest to the day when the State declared the area to be the first “National Park” of the country, is the fertility of this beautiful tropical rain forest complex.

The UNESCO later designated the area, “Dong Phayayen – Khao Yai Forest Complex”, to be the Natural World Heritage for everyone to conserve and nurture.

Only a small number of people have realized that the beautiful physiography of Khao Yai National Park as we see it today is the result of hundreds of million years of magical work of geological processes that have created geological sculptures on the Earth’s surface. The landscapes of this world heritage site inhibit its complexity through a series of mountain ranges and hills, large and small. Even though the area is covered with calm and peaceful forest area, the lithospheric plate hidden underneath, on the other hand, has a rather amazing story behind. Such story involves volcanic eruptions, sedimentation, crustal uplifting and the weathering and erosion of soil and rocks that periodically occurred through each of the geological time periods. These are challenges for all of us to go through the endless research study and work to solve these geological puzzles.

The Royal Thai Department of Mineral Resources (DMR) realizes how important to publish the geological information of this Natural World Heritage to the public to be informed and gain an understanding of the geological processes involved. The DMR publishes this book in hope that readers realize the value of this piece of land and nature, which is the heritage of the world that has been given to all the Thai people to cherish with care, to protect and to preserve it for eternity.

CONTENTS CHAPTER 1

The Northeastern Part and the Dynamic Earth 4

Hew Suwat Waterfall: From Hot Volcanic Ashes to the Prominent Beautiful Waterfall

28

Pha Kluay Mai Waterfall: From Hot Lava Texture to the Wilderness

30

Kaeng Hin Phoeng: Sculpture of the Water Stream on the Rock Floor

32

Scenic View Point at KM. 30: The Historical Map of the Mountain Ranges

34

Scenic View Point at Pha Diew Dai: Panoramic View in the Middle of the Forest

36

Khao Samo Pun Scenic View Point: The Inclined Mountain That Looks Like A Thai Cleaver Knife

38

Dinosaur Footprint: Traces of Ancient Animals in the Centre of the Forest

40

16

CHAPTER 4

CHAPTER 2

Geology of “Khao Yai”, From the Past to the 6 Present

The Origin of “Khao Yai” Terrain

Silurian - Devonian - Carboniferous Period (443.7 - 299 Ma) 7

The Long Journey Has Begun: Drifting from the “Gondwana”

8 Permian Period (299 - 251 Ma) The Submarine Kingdom of Khao Yai

Permo - Triassic Period 10 Furious Earth, Earthquake, Thundering Volcanic Eruption

Triassic Period (251 - 199.6 Ma) 12 The Origin of the Northeastern Highland, the Beginning of the Dinosaurs’ Legendary

“Khao Yai” Today

26

14

CHAPTER 3

Hew Narok Waterfall: The High Cliff and the Miraculous Power of the Water Flow

The Evolution of the “Earth”

Jurassic Period (199.6 - 145.5 Ma) Population Growth on the Fertile Land

Cretaceous Period (145.5 - 65.5 Ma) The Golden Age of Dinosaur, Heading toward the End

Paleogene - Neogene Period (65.5 - 23 - 2.6 Ma) The Period of Natural Sculpturing to Create Khao Yai

Quaternary Period (2.6 Ma - Present) Ready to be the World Heritage

The Origin of Natural Sculpture Khao Yai National Park 24

Investigation from Rock, Soil and Sand

The Geologist’s Work 18 Geological Survey Report of Khao Yai National Park

20

CHAPTER 5

46

What Does Khao Yai Give Us…?

48

Turning the Land over to Find the Geological Information Glossary of Geology Geological Map of Khao Yai National Park

44

Nature Will Live on Forever

“Ecotourism”: The Sustainable Use of Khao Yai National Park Area

22

42

Bibliography

49 51

The Northeastern Part and the Dynamic Earth

6

CHAPTER 1 The Northeastern Part and the Dynamic Earth The Evolution of the “Earth”

Since the beginning of the Earth 4.6 billion years ago, this planet has never been at rest. Deep down beneath the Earth’s surface, the heat accumulated from the decay of radioactive elements has caused the rocks to melt and become molten rocks or magma. The heat transferred within magma has created “convection current” of hot materials that keeps pushing the Earth’s lithospheric plates to move. The evidence of this dynamic earth has been recorded in the Earth’s materials leaving geological clue for further investigation of this amazing past event.

Jurassic Period 199.6 - 145.5 million years ago: The sedimentation on the continent continued through the sediment transportation of the braided streams on the vast flood plain.

Many plants and animals evolved.

The remains of these plants and animals accumulated with sediments and became fossils in the bed rocks, e.g., fish, turtle, crocodile and dinosaur.

Silurian - Devonian Period 443.7-416 - 359.2 million years ago: At that time, Thailand was under the sea and attached to the “Gondwana”, an ancient supercontinent, located in the Southern Hemisphere. Later, the “Indochina Plate” split from the Gondwana and being pushed toward the Northern Hemisphere.

195 million years

Triassic Period 251 - 199.6 million years ago: The subduction of the oceanic lithospheric plate continued until the Late Triassic when the Shan-Thai and the Indochina completely joined resulting in the uplift of the area along the suture zone or collision zone.

The eastern part of the Indochina sub-continent became a vast area of flat plain where sedimentation began on land. Fossils found in the sedimentary rocks of this period comprise various types of plants and animals, including dinosaurs, on the Northeastern Highland.

94 million years

Cretaceous Period 145.5 - 65.5 million years ago: The on-land sedimentation continued from the Jurassic to the Late Cretaceous then there was an extreme event at the end of the Cretaceous that greatly changed the environment resulting in the extinction of all dinosaurs. As a result, both meat-eating (carnivore) and plant-eating (herbivore) dinosaur fossils are most abundant in rocks of this period found on this Northeastern Highland.

50 million years

7 390 million years

Permo-Triassic Periods: During the changing periods from Permian to

Triassic, the oceanic lithosphere located between the Shan-Thai and the

Indochina sub-continents, subducted beneath both sub-continents

resulting in the moving toward each other of the two sub-continents.

The subduction caused extensive and violent explosion of volcanoes

all along the subduction zones during this time resulting in the great

extinction of many species of plants and animals in the area.

Permian Period 299 - 251 million years ago: The Shan - Thai Plate separated from the Gondwana and moved to the north toward the equator to the Indochina Plate.

The environment of these two continents at that time was the warm sea with a wide-spread of the sediments accumulated along the continental shelf and continental slope. Fossils found during this period are those of marine animals, e.g., fusulinids and ammonites.

Present

Paleogene - Neogene Period 65.5 - 23 - 2.6 million years ago: There was an uplift of the Northeastern Highland and the Phuphan Mountain Range during this time. As a result, major rivers played a key role on stream weathering and erosion of the rocky terrain and transported all sediments to deposit over the basin of the Northeastern Khorat during Late Paleogene time.

Neogene : Rivers continued to erode. Sediments accumulated along the river valleys, afl t plains and shallow lakes as a result of the erosion and transportation of wind and flash flf loating. The Neogene is the golden age of mammals, including apes, which is believed to be the human’s ancestor. Many mammal fossils including elephants, ancient rhinos, ancient horse, giant turtle and large crocodile were found in the sand pit in Chaloem Phra Kiat District, Nakhon Ratchasima Province.

Quaternary Period 2.6 million year ago - present: the last period of volcanic eruption that occurred along the southern rim of the Northeastern Highland. There was a violent change of weather during this period. High rate of erosion occur continuously resulting in the landscapes as being seen today. This period is still the golden age of mammals.

Apes have continually evolved and become the modern man.

The Northeastern Part and the Dynamic Earth

Carboniferous Period 359.2 - 299 million years ago: The oceanic plate subducted to the east under the Indochina Plate. At depth, the subducting part was melt due to high pressure and temperature and became molten rocks that intruded up to the Earth’s surface and exposed to form the volcanic chain along the subduction zone called “volcanic arc”. Fossils found in sedimentary rocks accumulated during this period include a number of marine animals, e.g., brachiopods and coral reefs.

Geology of “Khao Yai”

8

CHAPTER 2 Geology of “Khao Yai”, From the Past to the Present The Origin of “Khao Yai” Terrain

The Earth’s surface comprises the continents and the oceans that may look similar to the orange peel. In fact, the Earth’s surface consists of a number of lithospheric plates that include the Earth’s crust and the upper part of the upper mantle. The interior heat within the Earth originated from the decay of radioactive elements has caused the vast amount of materials in the lower mantle to become molten rocks or magma that move upward and become a convection current. This convection movement within the mantle has caused the continual movement of all the lithospheric plates through time.

Khao Yai area is another historical pages that record changes of the Earth. The story has begun since the two lithospheric plates that underlain Thailand, i.e., Indochina Plate on the east side and Shan-Thai Plate on the west side, separated from the ancient Gondwana in the Southern Hemisphere and drifted into the Northern Hemisphere. Simultaneously, living things evolved on the land surface. Through time, the evolution of lives sometimes has been temporarily paused or completely ended due to factors from both within and outside the Earth.

• Mid Oceanic Ridge • Oceanic Crust • Continental Crust

Lower Mantle • Convection current

• Upper Mantle

9

The Long Journey Has Begun: Drifting from the “Gondwana”

Million Years 443.7

299

251

199.6

Tracing back in time to the Silurian - Devonian, which is about 444 - 359 million years ago (Ma), the original piece of land, the “Indochina Plate”, presently located to the eastern part of Thailand, used to be a part of the Gondwana, which was the super continental lithospheric plate located in the Southern Hemisphere.

The Indochina Plate was pushed to continually move northward through the ancient sea toward the equator along with the sedimentation of marine sediments. The evidence of marine environment has been reported in Loei Province as marine animal fossils, e.g., coral reefs and radiolarian, indicating the sedimentation in the rather deep marine environment.

Toward the end of the Devonian, the western oceanic plate subducted beneath the Indochina Plate resulting in the volcanic island arc and the pushing up of marine sediments to form an accretion along the subduction zone.

The Carboniferous covers the period between 359 - 299 million years ago. During these times, the subduction of the oceanic plate continued until Late Carboniferous time. Sedimentation of sediments from marine and turbidity current occurred throughout the period as can be seen from the fossils evidence including algae, foraminifera and brachiopod found in the rocks of this period in Loei Province.

•Accretion of marine sediments along the subduction zone

145.5

65.5

2.6

Fossil Evidence • Lublinophyllum thailandicum, found in Loei Province.

These invertebrate and multicellular animals, similar to sponges, lived and flourished in shallow reefs and marine flf loor during the Early Carboniferous.

20 cm.

4.5 cm.

• Brachiopods, found in Loei Province.

These primeval marine invertebrate animals characterized by two bilaterally symmetrical valves. Brachiopods were usually attached to a solid substrate with a muscular structure called a pedicle.

Brachiopods were abundant during Palaeozoic Era. Most went extinct at the end of the Permian.

• Stromatoporoid found, in Loei Province.

These invertebrate and most primitive of multicellular animals were abundant in Devonian - Carboniferous Periods.

Extinct sessile benthic marine organisms of uncertain biologic aff ifinities 8 cm. that were abundant in Devonian time.

•The oceanic plate subducts beneath the Indochina Plate.

Present

Silurian - Devonian - Carboniferous Period

Silurian - Devonian - Carboniferous Period (443.7 - 299 Ma)

Permian Period

10

Permian Period (299 - 251 Ma) The Submarine Kingdom of Khao Yai

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

11 the reach of sunlight, occupied the area between the two continental plates. Such environment caused the sedimentation of sediments along the continental shelf and continental slope widely found as limestone, chert and shale. Fossils of marine animals were also abundant in limestone, e.g., fusulinids, coral reefs and ammonites. Rocks that are the main evidence of the Permian are located to the northwestern part of the present-day Khao Yai National Park.

Fossil Evidence

15 cm.

• Corals, found in Loei Province.

Corals, marine invertebrate organisms, are common in shallow and warm inter-tropical seas where sunlight can be reached. Fossils of corals are usually found in limestone, especially those of the Permian.

• Fossils of fusulinid, found in Phetchabun Province.

Fusulinid, or “Khot Khao San” in Thai, was a simple - celled animal characterized by a multi-chambered elongate calcareous microgranular test, commonly resembling the shape of a grain of rice, its small size with approximately 0.5 - 1 cm long. Its habitat was in warm shallow sea.

Fusulinid began to occur in Late Carboniferous time and became extinct at the end of the Permian. Because of that, it is very useful to use fusulinid as an index fossil for the rock unit formed during 299 - 251 million years ago.

15 cm.

0.5 - 1 cm.

• Ammonoids, found at Khao Chon Tho, Phetchabun Province.

Ammonoids are extinct cephalopod of the same class with the Coleoidea (octopus, squid and cuttlefish) characterized by thick external shell that is symmetrical and coiled in a plane with the appearance ornament and suturing. Most ammonoids float near to the sea surface.

• Alatoconcha fossil, found in Saraburi Province.

Shallow marine animal of Alatoconchidae that had adjusted to habitat in the warm sea area in Thailand.

The fossils were found in the rock of Saraburi Group in a number of provinces including Saraburi, Lopburi, Nakhon Ratchasima, Nakorn Sawan. It was also found in rocks of Ratchaburi Group in Chumphon Province.

19 cm.

19 cm.

Permian Period

After the cessation of the subduction of the ancient oceanic lithospheric plate beneath the Indochina Plate around Late Carboniferous, the Shan - Thai, which constitutes the original landmass of Western Thailand, began to separate from the Gondwana and moved northward to the equator until it was near to the western part of the Indochina Plate.

During the Early Permian, there was a relatively calm and warm ancient sea, with

Permo – Triassic Period

12

• Volcanic ash • Volcanic dust

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

13

Permo - Triassic Period

Furious Earth, Earthquake, Thundering Volcanic Eruption Permo – Triassic Period

• Flow Band

•Driving Force of the Mid Oceanic Ridge has pushed Oceanic Lithospheric Plates to subduct causing the Violent uplift of Indochina Plate and the explosion of the volcanoes along the subduction zone.

During the end of the Permian and the beginning of the Triassic, a series of oceanic ridge began to rise along the area between the Shan - Thai and Indochina Plates.

The event had caused the subduction of oceanic lithospheric plate beneath those two continental plates, which in turn rapidly moved toward each other along with violent volcanic explosion along those two subduction zones resulting in major extinction of many plants and animals, especially the marine ones.

On the Indochina landmass, there has been a report on the finding of agglomerate, tuff, rhyolite, andesite and basalt along the area ranging from Loei Province down to the southwestern rim of the Khorat Plateau. Some of the volcanic rocks were underlain with

• Agglomerate

intrusive igneous rocks, i.e., along the western and the northeasternmost part of Khao Yai National Park.

The volcanic eruptions spilled out pyroclastic sediments of various types into the atmosphere leaving all the volcanic dust of very tiny sizes to be blown by the wind for great distance and then deposited to become tuffaceous rocks. Hot volcanic ashes, along with gases and water vapours, spewed out from volcanic vent and fell down on the slope of the volcanoes and flowed along the slope, cooled down and turned to ash-flow tuff or ignimbrite. Large pieces of pyroclastic materials such as volcanic bombs or lapilli always deposited near to the volcanoes to form agglomerate.

• Agglomerate found in Hew Suwat Waterfall Area clearly showing the alignment of rhyolite.

Triassic Period

14

Triassic Period (251 - 199.6 Ma)

The Origin of the Northeastern Highland, the Beginning of the Dinosaurs’ Legendary

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

Later, running water had played a key roll on surface erosion of the high grounds and carried sediments, along with the remains of plants and animals, to deposit in the lowland area of the continent during Triassic time.

The Triassic is the time when thet vertebrate animals such as dinosaurs, fresh - water crocodiles, reptiles, turtles, as well as a number of seed plants, began to rise. There has not any report on the finding of Triassic sedimentary rocks in Khao Yai National Park.

Fossil Evidence • Bones and teeth of Phytosaur, found in Loei Province.

Phytosaur, the ancient animal similar to the ancient crocodile lived through the Late Triassic, found only jaws and teeth fossils.

25 cm.

• Isanosaurus attavipachi, found in Chaiyaphum Province.

The oldest plant-eating dinosaur, with an average length of 13 - 15 meters, lived during the Late Triassic around 210 million years ago. Its neck, tail and back bone fossils were found in the rock of the Nam Phong Formation.

110 cm.

Triassic Period

The subduction of the oceanic plates continued to occur until the Shan - Thai Plate joined with the Indochina Plate to become one piece of landmass during the Late Triassic. The event had resulted in the closing of the ancient sea, the uplift of the area along the suture zone (boundary zone located between the two continental plates) and the formation of the vast flat plain over the eastern part of the Indochina Plate.

15

Jurassic Period

16

Jurassic Period (199.6 - 145.5 Ma) Population Growth on the Fertile Land

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

17 with strong and turbulent running water resulting in the sedimentation along both sides of the river plain. The sedimentation continued until the time about the end of Jurassic time and the beginning of Cretaceous Period, when the sedimentation environment changed to the braided stream environment.

Sediments produced by such environment later formed the rock unit of Phra Wihan Formation. Rocks of these two formations can be found in the central and the eastern parts of Khao Yai National Park. Such fertile environment contributed by running surface water during the Jurassic had resulted in the flourishing of plants and animals, especially those big - and small - sized dinosaurs.

Fossil Evidence

• Nam Chan Fishes: Lepidotes buddhabutrensis, found in Kalasin Province.

30 cm.

• Stegosaurid dinosaur, found in Kalasin Province.

Jurassic plant-eating Stegosaurid, a 15 meter long dinosaur, was firstly found in the rock of the Phu Kradueng Formation. The fossils found include the spine bone with the part that used to be connected to the back plate.

35 cm.

Jurassic Period

During this period, the pre-existing volcanic belt uplifted to form mountains in Khao Yai National Park area. The mountain range extended along the areas of Saraburi Province up to Loei Province with its slope dipping eastward. Most of the running water washed down all sediments from the high ground to accumulate and form large fluvial plain deposits. Through time, these deposits then later became sedimentary rocks of the Khorat Group.

According to the sedimentation pattern of the sedimentary rocks of the Phu Kradueng Formation indicates that sediments found during Middle to Late Jurassic times deposited in the environment of meandering streams

Cretaceous Period

18

Cretaceous Period (145.5 - 65.5 Ma)

The Golden Age of Dinosaur, Heading toward the End

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

of extensive mega volcanic explosion. Some believe that the Earth was hit by large meteors that caused tremendous amount of terrestrial dust to float into the sky and blocked the sunlight from reaching the ground surface for a very long period of time. This might have resulted in death of many plants and animals, especially the big ones like dinosaurs that ended up in extinction. Recent findings confirm the meteor hypothesis through the finding of iridium element, which is normally abundant in the space and meteorite, accumulated in an anomalous amount in thin layers of sedimentary rocks occurred during the boundary between Cretaceous and Paleogene times worldwide.

Fossil Evidence

300 cm.

• Bone fossils and teeth of the plant-eating dinosaur (sauropod) “Phuwiangosaurus sirindhornae”, found in Kalasin and Khon Kaen Province.

Phuwiangosaurus sirindhornae, a 15 - 20 meter long planteating dinosaur lived in the Early Cretaceous. The fossils of this long-neck sauropod were found in the rock of the Sao Khua Formation. The name “Sirindhornae” was given to highly honour Her Royal Highness Princess Maha Chakri Sirindhorn, who is interested in paleontology.

6 cm.

20 cm.

During the Cretaceous, braided streams stil played an important role as major weathering and erosion agent in the northeastern part of Thailand where sand sediments were washed from its source and continued to deposit until Late Cretaceous when the environment changed to desert and salt - water lake. Due to the hot and arid weather, vast amount of water in the lake evaporated leaving

• Tortoise shell “Isanemys srisuki”, found in Nong Bua Lamphu Province.

The fossil found was an almost complete shell of an ancient fresh - water tortoise lived during the Early Cretaceous.

30 cm.

• Teeth of fish-eating dinosaur “Siamosaurus suteethorni”, found in Khon Kaen Province.

The fossils found were sharp ended teeth of the seven meter long fisheating Siamosaurus sutheethorni. This long and narrow jaw dinosaur lived during the Early Cretaceous.

• Fossil of Psittacosaurus sattayaraki, found in Chaiyaphum Province.

This small plant-eating dinosaur with its mouth similar to parrot beak, quick movement, lived during the Eariy Cretaceous. The body is approximately 1.5 m long. Fossils found include molar teeth and the upper and lower teeth.

Cretaceous Period

behind evaporites that later became thick beds of rocksalt and potash minerals in the northeastern part of Thailand.

Dinosaur fossils have been found within rock beds of Cretaceous period. Footprints of theropod dinosaurs were reported in Khao Yai National Park. The footprint occurred on Cretaceous sandstone piece washed down and found next to Lam Sai Yai river in Nadi District, Prachinburi Province.

Cretaceous is the golden age of dinosaur until the end of the period when the great extinction of dinosaur emerged worldwide, including Thailand. Some scientists believe that the event occurred as a result

19

Paleogene - Neogene Period

18

Paleogene Period (65.5 - 23 Ma) Neogene Period (23 - 2.6 Ma)

The Period of Natural Sculpturing to Create Khao Yai

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

19 Khoratpithecus piriyai or Khorat ape, which is one of the closest ancestors of orangutans, was found along with other fossils, e.g., elephant, rhinos, horse, large tortoise and crocodile in the sand pitch located in Chaloem Phra Kiat District, Nakhon Ratchasima Province.

Fossil Evidence 15 cm.

• Tetralophodon elephant teeth, found in Nakhon Ratchasima Province.

Tetralophodon elephant was the primitive types of mammals found during the Neogene.

• Fossil of Maemohcyon potisatifi, found in Mae Mo District, Lampang Province.

A new meat - eating, large sized, of the Amphicyonidae Trouessart Family with a combined dog - bear characteristics.

The fossils found included 4 molar teeth.

2 cm.

• Khoratpithecus piriyai, found in Chaloem Phra Kiat District, Nakhon Ratchasima Province.

This Khorat ape has a special characteristic, which are: large size, the same size as the present orangutan. The fossil found is the best piece ever reported in Thailand.

During the Paleogene, Indian continental plate rapidly moved from the south and collided with Eurasian continental plate resulting in the uplift of the Khorat Plateau, as well as created faults, fractures and joints in rock units in the area. Major rivers then played a key role on erosion, transportation and deposition of sediments. The period is truly the beginning of the time the nature began to carve the Khorat Highland and Khao Yai National Park to become as it is today.

7 cm.

15 cm.

• Parambassis paleosiamensis ffi ish bone, found in Phetchabun Province.

Fish bones found in sediments of the Paleogene belong to Parambassis group, Ambassis family, with 7.5 length from head to tail.

Paleogene - Neogene Period

River erosion continued until the Neogene. Most of these sediments were washed down to accumulate along the flat plain and shallow water lake. Neogene is the golden age of the mammals, including ape as supported by the study on fossils of

Quaternary Period (2.6 Ma - Present)

20

Ready to be the World Heritage

Quaternary Period

According to the geological time scale, the Quaternary is the last period that covers the time from 2.5 million years ago to the present. The weathering and erosion continued to work on rocks located within Khao Yai National Park from the previous period. Running water was still the main weathering and erosion agent. The erosion occurred deep into the rock unit to form steep valleys and washed all sediments, rock fragments, gravels, sand and mud to deposit along the bottom of the valleys, hill slopes and streams. At the same time, running water cut through the rock beds to create various types of landforms in the area.

The weathering and erosion processes gradually changed the highland or plateau to a number of smaller highlands called mesa and butte. These processes also carved a cuesta from a hill with gently mono incline rock beds. Sediments derived from the

weathering and erosion process combined with organic matters from the remains of animals and plants to form a fertile soil that is suitable for growing crops, plants and trees that soon cover the area to become a piece of forest of Khao Yai. This forest is a habitat for large and small animals. Volcanic rocks in certain areas were weathered and eroded to become salt lick area that are rich in illite, kaolinite, calcite and rocksalt, the most important source of elements for wild animals.

Fossil Evidence • Molar teeth of Hyena Crocuta crocuta found in Nakorn Ratchasima Province.

Hyena is a carnivore. According to the skill and teeth found, it is estimated that it had a body of 1.0 - 1.6 meters long. Hyena lives in the open and dry area. This can clearly imply the Pleistocene’s weather during the Early Quaternary.

10 cm.

Million Years 443.7

299

251

199.6

145.5

65.5

2.6

Present

21

Quaternary Period

3 cm.

25 cm.

• Rhinoceridas’ bone, found in Kalasin Province.

Rhinoceridas, an ancient animal, had a characteristic similar to the present rhinos.

• Grinder teeth of the giant panda “Ailuropoda melanoleuca baconi”, found in Chaiyaphum Province.

The giant panda, Ailuropoda melanoleuca baconi, is the meat-eating mammal lived in the temperate to cold areas. The fififinding of the bones of giant panda in Chaiyaphum Province informs us that the area used to have cold weather during the Quaternary.

“Khao Yai” Today

22

A

C

meters 1200 1000 200 600 400 200 0

A

meters 1200 1000 800 600 400 200 0

C

meters

B

1200 1000 200 600 400 200 0

meters

D

1200 1000 200 600 400 200 0

CHAPTER 3 “Khao Yai” Today

It took nature hundreds of millions of years to create the landscapes of Khao Yai National Park that have been through various geological processes, which still continue to, on one hand, destroy, and on the other hand, create natural balance of the world cycle.

B

LEGEND Sedimentary Rock Qa Alluvia gravel

Age

Holocene Qt Terrace gravel Pleistocene JKpw Phra Wihan Formation Lower Cretaceous Jpk Phu Kradueng Formation Jurassic Psb Sabbon Formation Middle-Upper

Permian

Igneous Rock TRgr PTRv

Granite Volcanic Rocks

Upper Triassic Permian - Triassic

The area of Khao Yai National Park covers areas of several provinces including Saraburi, Nakhon Ratchasima, Prachinburi and Nakhon Nayok. The name “Khao Yai” has been given due to the large mountain ranges of the park. These mountain ranges are underlain with rocks of various types and unconsolidated sediments. All of these combined to become the geological heritage that have been created through a long period of time.

Located along the northwesternmost part of the national park, the area is underlain with the oldest rocks ever found in Khao Yai National Park. Sedimentary rocks of this area comprise limestone, shale and chert of Permian age. These rocks belong to the Saraburi Group deposited as chemical sediments in the ancient marine environment along the continental shelf and continental slope.

Pyroclastic sedimentary rocks and volcanic rocks of the Permo-Triassic were reported over the western and northeastern parts of the national park. The rocks formed during the transition period from the Permian to the Triassic covering almost half of the area of the national park. These rocks comprise volcanic agglomerate, tuff, rhyolite, andesite and basalt. Some parts of this rock unit are underlain with intrusive igneous rocks.

Rocks located over the central and eastern parts of the national park comprise

alluvial sedimentary rocks of the Khorat Group including sandstone and mudstone of Phu Kradueng Formation. The rock unit overlies the pyroclastic and volcanic rocks of PermoTriassic period located to the central part of the national park along the roadway from Mo Singto to the sharp-curve located next to the Pha Diew Dai Viewpoint. These volcanic rocks represent the boundary unit between the sandstone unit of Phu Kradueng Formation and the overlying sandstone of the Phra Wihan Formation.

The southernmost part of the national park is underlain with unconsolidated sediments of gravels, sand and mud of Quaternary time representing the result of erosion caused by running surface water over sandstone of Phra Wihan Formation. Sand and gravel sediments were then washed down to accumulate along the streams.

Geological processes have continued its work through time creating various rock types in the national park. Furthermore, the interior force of the Earth also lifted up the northeastern highland resulting in the disintegration and transportation of sediments down stream leaving behind records of various geological structures, e.g., fault, fractures and joints, to occur all over the rock beds.

“Khao Yai” Today

Turning the Land over to Find the Geological Information Geological Map of Khao Yai National Park

D

23

The Origin of Natural Sculpture, Khao Yai National Park

24

The Origin of Natural Sculpture, Khao Yai National Park This forest has its legend. Many may be familiar with Khao Yai as one of the tourism sites that provides an outdoor natural classroom. In fact, Khao Yai has hid a mysterious past that many have told its legend for a long time until now.

The large piece of the tropical evergreen forest located between the northeastern highland and the central floodplain is known as “Dong Phaya Fai” or “Dong Phaya Yen”.

The legend has long been told about its deep tropical rain forest that contains fierce wild animals, malaria, and mysterious legends for a long time. All these have created fearsome to many who had traveled through this forest.

Until B.E. 2502 (A.D. 1959), His Excellency General Sarit Thanarat, Prime Minister, made an official trip to the northeastern part and realized the importance of conserving the nature and its environment, especially the forest resources.

He officially designated the forest area of Khao Yai to become the first national park of

the country. The national park covers an area that occupied parts of four provinces, which are Prachinburi, Nakhon Ratchasima, Nakhon Nayok and Saraburi. Later, there have been other announcements on the establishment of Thab Lan and Pang Sida National Parks in the adjacent pieces of forest. The combined piece of forests has become the largest national park forest of the country. Khao Yai National Park has been recognized as one of the top five national parks of the world with best management and has been announced to be the “Natural World Heritage” during the World National Park Congress held in the USA in 1972. It has been one of the things for the country to be proud of at all time.

General Information on Nature Khao Yai National Park covers an area of approximately 2,168 km2. The physiography of the park comprises wide fields alternated with rich forest. The eastern part of the park is covered with hill evergreen forest and tropical rain forest. The northwestern part of the park is covered with mixed deciduous forest, whereas the dry evergreen forest is located along the area in Nakhon Ratchasima and Prachinburi Provinces. Over the area where agricultural activity used to take place has become savanna forest or range land.

There has been a small portions of dipterocarp forest existed in the park.

25 The Origin of Natural Sculpture, Khao Yai National Park

Wild animal is one of the most important elements of Khao Yai ecological system that has greatly contributed to the dynamics of the park’s development. According to the survey result of researchers and park rangers, there have been many types of animals found in the area. The mammals include: 16 types of meat-eating (carnivores) animals, a type of elephant, 7 types of hoofed animals, 3 types of insect-eating animals or insectivores, 6 types of rodents, over 25 types of bats. In addition, there are 293 types of birds and approximately 70 types of reptiles and amphibians found.

The piece of Khao Yai National Park forest provides a watershed area for a number of rivers, e.g., as the headwater for the Nakhon Nayok River and the Prachinburi River that flow down and join to form the Bang Pakong River; the Lam Takhong that feeds people in Nakhon Ratchasima Province; and as the headwater of the Mun River, which is considered as the main blood vessel that feed all walk of lives in the southern part of the northeastern highland.

The Mun River gradually flows westward across the region to join the Mekhong River in Khong Chiam District, Ubon Ratchathani Province.

Geology and the Origin of Natural Sites within “Khao Yai” Landforms are physical, recognizable, form or feature of the Earth’s surface, having a characteristic shape, e.g., mountain, plateau, plain, etc., as produced by natural causes, which are geological processes that work through time to make up the Earth’s surface configuration as seen today.

The landscapes of Khao Yai National Park exhibit a series of mountains and ranges that are underlain by volcanic rocks and sedimentary rocks. The original ground was eroded and washed away by surface running water. Besides, all faults, joints and fractures occurred within the rock unit act as a catalyst to speed up the weathering and erosion process. Small fractures in the rock mass can start to form a stream line, which then be developed to become the main river later.

The power of the running surface water change from season to season. Running water erodes bedrocks on both sides to form cliffs and flows to the lower ground to form waterfalls. Confronting the resistive rocks, flowing water would be forced to flow through the weaker paths, such as along rock cracks, fractures or fault that cut through the rock units, leaving behind the resistant beds as cataracts or rapids in the streams.

Hew Narok Waterfall

26

Hew Narok Waterfall:

27

The High Cliff and the Miraculous Power of the Water Flow

The Hew Narok Waterfall is located to the southern part of Khao Yai National Park.

In the past, the area comprised two rock types, the underlying pyroclastic rocks and the overlying sedimentary rocks of the Khorat Group. Until Early Paleogene time, the Khorat Plateau had uplifted resulting in the forming of fractures, joints and faults within rock formations making it easy to be weathered and eroded.

Rain water and water stream of Khlong Tha Dan eroded much of the sedimentary rocks of the Khorat Group and continued to vertically

cut into the rock unit until it reached the underlying tuff bed formed from volcanic ash flow. The powerful water flow, in cooperated with tremendous amount of water during the rainy season, violently cut along the fractures vertically eroding rock blocks and fragments and created high cliffs and waterfall. This never-ending process has continued to carve the rock beds making the cliff to move toward the upstream direction.

• Texture of tuff

Retreat on the Steep Cliff The steep cliff of the Hew Narok Waterfall originally was not located at the present location. Running water eroded the rock cliff to fall apart making the cliff front to retreat toward the upstream direction through time. The eroded rock fragments and blocks fell down to the bottom of the valley below and form the wonderfully beautiful landscape.

Hew Narok Waterfall

The one-hundred-meter-high cliff of the Hew Narok Waterfall is a result of the amazing power of the running water that has intensely eroded rocky cliffs for a very long period of time. The name “Hew Narok” has been achieved from its thrilling height with almost 90 degrees steep and an “elephant graveyard.”

Hew Suwat Waterfall

28

Hew Suwat Waterfall:

29

In the midst of the shady rain forest of Khao Yai, the scenery of Hew Suwat Waterfall is the spectacular scene of the water stream flowing out from the cliff over the deep valley, similar to long water curtain. The strong water flow turbulently eroded the rocky beds to create deep reservoir underneath. The touch of the peaceful and refreshing atmosphere of the waterfall make it hard to believe that the area once used to be baking hot of volcanism many millions of years back.

Hew Suwat Waterfall

From Hot Volcanic Ashes to the Prominent Beautiful Waterfall

The violent volcanic eruption through the rhyolite flow, which accumulated around the volcanic vent had resulted in the breaking of rock chunks that exploded into the atmosphere and fell down to mix with the hot lava flow that oozed out from the volcanic vent. Once these pyroclastic sediments cooled down, it formed volcanic agglomerate bed where the Hew Suwat Waterfall is originated.

Similar to that of Hew Narok Waterfall, the Hew Suwat area once used to be overlain by sedimentary rocks of the Khorat Group.

Years after years that these cap rocks were eroded by surface running water that cut deep

down to reach the volcanic rock bed below.

Apart from the banging of water that cause the rock to erode, the water stream also carry rock fragments, gravels and sand grains to abrade and erode the rock bed beneath the cliff of the waterfall. The cutting continued for a long period of time resulting in the thinning of the top bed at the waterfall front, which then finally broke down. The front of the waterfall then moved upstream creating the Hew Suwat Waterfall as being seen today.

The cool atmosphere of the water flow of Hew Suwat Waterfall has left no clue on the heat of volcanoes in the past, leaving behind evidence that awaits to be explored • The formation of the rocky cliff that has been and challenge us to search for the miraculous cared by running water that has resuit in tumbilng past of the land. down and eroded rocks.

The Puzzle in the Rock: Solving the Clue to the Deposition It is noticed that agglomerate found around the Hew Suwat Waterfall displays a gradual and progressive change in particle size from coarse grains at the base of the bed to fine grains at the top. The characteristic is referred to as

“graded bedding”. It happened when volcanoes exploded and spewed out pyroclastic sediments and ashes into the atmosphere. Once these materials reached its highest levels, it began to fall. The large pieces of pyroclastic materials are among those that fell first, followed by the smaller and lighter particles. The process kept repeating when another eruption occurred.

When these pyroclastic sediments cooled to form agglomerate, which inhibits gradual change of particle sizes in each rock layers from coarse to fine, alternately, as seen today.

• Valcanic agglomerate found around Hew Suwat Waterfall showing the alternate layers of fine and coarse grains due to gravity force.

Pha Kluay Mai Waterfall

30

Pha Kluay Mai Waterfall:

31

From Hot Lava Texture to the Wilderness

• Potholes at Pha Kluay Mai Waterfall Pha Kluay Mai Waterfall is another waterfall formed in one of the tributary streams that combined to become the Nakhon Nayok River. The waterfall was formed in a similar way as that of the Hew Suwat Waterfall.

The only difference for the Pha Kluay Mai Waterfall is that the underlying volcanic rock unit is rhyolite with flow bands instead of the agglomerate bed.

The erosion caused by water stream along the structures such as fracture, joint and lava flow within the rock has created beautiful landforms such as waterfall, rapids and the bend of the river. These features hold the water for the area and all the plants, attracting a large group of butterflies to come and search for food along the sand sediments and rock boulders. Such scenery is so exciting that one cannot wait to take some photographs for their good memory.

Walking upstream from the rock outcrop above the Hew Suwat Waterfall, visitor may observe the change of rock type from agglomerate to rhyolite. A large number of large and small potholes distributed all over

the bedrocks may also be observed as a result of erosion process caused by running water.

The timing correlation between the agglomerate bed and the rhyolitic flow around the Pha Kluay Mai Waterfall is still unclear whether which one came first. However, considering based on the terrain elevation, it is possible that the agglomerate occurred after because it overlays the rhyolite flow.

The Thermal Design Beautiful patterns created by nature that occur on the rock surface around the Pha Kluay Mai Waterfall. These rocks, at one time, used to be hot lava that oozed up, flowed, and burnt out things along its path. While the lava with high viscosity due to the high silica (SiO2) content slowly flowed and cooled down with crystallization of minerals, lava masses became solid while being pulled along its flow direction resulting in frozen patterns in the rock that beautifully designed by the heat.

Pha Kluay Mai Waterfall

After the volcanic eruption occurred many million years ago, viscous lava slowly flowed from the volcanic vents into all directions. With temperature of a thousand degrees Celsius, the lava burnt down everything along its path. The viscous lava, when cooled, created special textures that are as beautiful as those sculpted and painted by the artists. This is truly a work of nature that created master pieces of art for all man to admire in the middle of the jungle.

32

Kaeng Hin Phoeng

Kaeng Hin Phoeng:

Sculpture of the Water Stream on the Rock Floor Kaeng Hin Phoeng is the eye-witness evidence of the power of water stream that carved onto this vast rock floor to form irregular rock surface. Potholes, natural arches, small waterfalls and rapids are also displayed in the area. This miraculous place makes us wonder about how long the forest of Khao Yai can hide this heavenly place before anyone can discover it.

• Erosion by running water along fractures is the main process which forms streams, rapids and valleys.

33

Who would have thought that holes and hollows on the rocky bed that familiar to our eyes are the key evidence that reflect the power of the water streams and the creation of the nature?

“Potholes” are the work of nature occurred as a result of the force of the stream current during the rainy season that carry all gravels and sand to whirl around, grind and abrade the rocky bed to form holes and hollows that soon getting larger to form “potholes” or the features with the “characteristic of pot”.

The erosion occurred along fractures and the bedding plane within sandstone bed of the Lam Nam Sai Yai has created a large area of rock-rapids across the watercourse way. The narrow watercourse has resulted in a never-ending process of high erosion rate over the bedrock due to the powerful and tremendous amount of water in the rainy season alternated with the slow flowing through the rapids during the summer time.

“Kaeng Hin Phoeng”, is well-known for adventure rafting activity of Lam Nam Sai Yai. Kaeng Hin Phoeng is characterized as a large sandstone bed with gently dip to the south. The sandstone is coarse-grained, poorly sorted, with the bed strikes in the E-W direction across the Lam Nam Sai Yai, which flow from north to south. There are several sets of fracture and joint shown within the rock unit, however, only two sets control the development of Kaeng Hin Phoeng, i.e., the one that parallel to and the other that perpendicular to the rock bedding.

Water streams at various seasons have cut through fractures and joints, breaking rocks into fragments, cutting deep into the rock bed, changing the slope and the level of stream bed. These have created small waterfalls along the watercourse. The great power of water stream is more than enough to carry all gravels and sands to whirl around and kept in motion by eddies or the force of the stream current to grind the rocky bed and create potholes of various sizes all over the place.

This can be evident on the surface of rocky bed, rapids and stream beds during the dry season. Furthermore, the other geological feature that can be seen at this famous Kaeng Hin Phoeng is the “cross bedding” that can be used to indicate the direction of paleo- or past current.

Kaeng Hin Phoeng

“Potholes” on the Rocky Bed

34 Scenic View Point at km. 30

Khao Wang Hin Khao Pha Chaeng Khao Rim Hua Baan Khao Phaeng Ma Khao Khao Tha Ma Prang Tham Din Saeng Kham

Limeston e Volcanic rocks

Various rock properties and geological structures are the main factors controlling the formation of various topographic features as can be seen in the topographic map.

Limestone-volcanic rock lt Fau

N Triangular facet Scenic View Point at KM. 30

35

Scenic View Point at KM. 30 : From the Scenic View Point at KM. 30, one can admire, as far as one can see, the scenery of the mountain ranges. Each of these mountains tells us about the natural history, background, origin, as well as what have been hidden behind geological puzzles for generations to explore the legend of the mountain range.

To reach the Viewpoint at KM. 30, one can take the forest-scenic road to Khao Yai National Park from Pak Chong District. This is the first Scenic View Point that visitors always stop to admire the beauty of the mountain overlooking the northern part of Khao Yai National Park.

Looking north from the viewpoint, one can see the landscapes showing high and low areas in comparison with the topographic map, which is a reproduction of the 3D topographic features such as mountain, valley, tributary, plain, or any physiographic forms originated from rocks of different types and ages, including the man-made ones, into a 2D map.

The mountain ranges seen as the furthest one exhibits cliffs. The mountain has sharp, upright and uneven tops with some of the area showing brown rock cliff similar to caves. These are the Permian (299 - 251 Ma)

Limestone mountains, namely, Khao Phaeng Ma, Khao Pha Chaeng, Khao Wang Hin and Khao Tham Din. Next from the mountain mentioned down to the Scenic View Point is underlain with Permo-Triassic (approximately 260 - 254 Ma) volcanic rocks. It is obvious to see the cliff that was formed as a result of the cutting of normal fault through the mountain ridge and trough. The movement of the rock located above the fault plane would reveal the triangular facet, which can be recognized from a distance even though it is being covered with dense vegetation.

Furthermore, looking carefully along the foot hills, one can see the characteristic of the flood plain of the Lam Takhong and its tributaries.

(CaCO3) compound in the warm sea along with the remains of animals such as shells and corals. Limestone has the hardness that is a little bit harder than our nails and easily dissolved in acid. When rainwater, a diluted acid, reacted with and dissolved limestone, it would have resulted in steep cliffs with sharp and rough surface, usually on the top of the mountain, as well as burrow and caves that water can seep through.

The Triangular Facet over the Volcanic Rock Mountain Once that faults cut through the pre-existing volcanic rock mountains formed from the erosion of running streams to form mountain ridges and troughs, the portion that located Natural Sculpture on the Limestone above the fault plane slipped down Mountain according to the Earth’s gravity to open the Most of limestone mountains are originated triangular facet on the other lower side of from the deposition of calcium carbonate the fault plane.

Scenic View Point at KM. 30

The Historical Map of the Mountain Ranges

Scenic View Point at Pha Diew Dai

36

Scenic View Point at Pha Diew Dai:

Panoramic View in the Middle of the Forest

Pha Diew Dai Scenic View Point is the biggest and the highest point of Khao Yai National Park. The site is open for everyone to see a natural Scenic View Point, the shape of mesa or a flat-top mountain that formed from stream erosion. It is like learning to understand a new lesson on geology of this rich piece of forest.

To reach the Scenic View Point, take the road from Nong Khing intersection up across Khao Khiew through sedimentary rock beds of the Khorat Group, including that of Phu Kradueng Formation from the intersection, then climb into that of Phra Wihan Formation until reaching the top of Khao Khiew. There is a parking space for Pha Diew Dai Scenic View Point once traveling through the sharp curve. Then walk to the other side of the parking lot, continue to walk until reaching the open space of approximately 5 meters wide located on the top of the high cliff of Pha Diew Dai. It is a view point to see “mesa”, a flat-top mountain that formed as

a result of water erosion through the mountain that underlain with gently dipping rock beds of different resistance. Mesa is the outstanding landform of rock of Khorat Group that comprises various types of sedimentary rocks.

The uplift to form mountains that have been eroded for a very long time through geological time scale created this rocky ground on the top of the high and steep cliff namely “Pha Diew Dai”, which underlain by sandstone of Phra Wihan Formation. The sandstone is composed of white and pale brown sand, well sorted, thick bed with cross-bedding. The rock also clearly shows the evidence on the changing of

water flow directions of the braided streams in the past. Water streams cut deep into the rock unit along the escarpment slope washing away all the supporting rock below leaving behind the top bed of approximately 1 meter thick to stick out of the cliff over the deep alley with dense vegetation and unpredicted depth.

Weathering process has disintegrated sandstone to white sand grains that being washed down to the cycle of deposition to form a ground for various types of forest to grow beautifying the area of this lone cliff.

• Plateau

37

• Mesa

The Miraculous Mesa

Stream Evidence on Cross -bedding

Cross-bedding, an evidence of ancient sedimentation in large braided streams, is characterized by the bedding that dips from its normal bedding due to the changing direction of the river stream. This has resulted that the sediments can no longer deposit to form horizontal beds but dip toward the down-stream direction.

Scenic View Point at Pha Diew Dai

• Butte

Mesa is an outstanding landscape created by stream erosion on various sedimentary rocks of the Khorat Group.

These gently-dipping rock beds have different resistance to erosion. The process transformed the large flat plain to a number of flat-top mountains with the area of no more than 10 km2 each with steep hill side, for instance, Phu Kradueng and Phu Luang.

If the erosion process continues until the flattop area become less than 1 km2, it is then called “Butte”.

Khao Samo Pun Scenic View Point

38

Khao Samo Pun Scenic View Point:

The Inclined Mountain That Looks Like A Thai Cleaver Knife Khao Samo Pun is a sandstone mountain with an inclined outline at the top that makes it look similar to the “E-To” cleaver knife. This type of mountain is sometimes referred to as “Cuesta”. On the top of mountain, wild flowers are usually flourished around the end of rainy season to the beginning of the winter. The miracle of the nature attracts many visitors to explore and gain an experience of a lifetime.

39

• Sandstone

• Volcanic rock

Strange-looking “Phukhao Meed E-To”

A mountain with a shape that is similar to the “E-To” cleaver knife is referred to as a Spanish word, “Cuesta”. Looking horizontally towards the mountain from the direction that is perpendicular to the gently dipping (5-10 degrees) direction (or parallel to the strike of the bed), one would see the outline of the mountain with one face long and gentle (dip slope) and the other steep or even cliff-like. Mountains with this characteristic can be found in many places, e.g., Khao E-To, Prachinburi Province and along the Dong Rak Mountain around Phra Wihan Stone Sanctuary in Sisaket Province.

Khao Samo Pun Scenic View Point

Khao Samo Pun is a part of mountains along the rim of Khorat Plateau that can be seen from the viewpoint located just before getting to Khao Yai National Park on the side of Prachinburi Province. The formation of the ridge is controlled by the differential erosion of the gently dipped or inclined strata. The scene from the viewpoint overlooks the western side of Khao Samo Pun displaying the sandstone beds of Phra Wihan Formation interbeded with siltstone and mudstone beds that have been eroded out due to the lower resistance, leaving behind the resistant sandstone bed as a steep ridge on the top of the mountain.

Looking from the rock quarry for Khlong Mai Plong Reservoir, one may clearly see the side-view of Khao Samo Pun with its outline that look similar to an “E-To” cleaver knife with the landform of “Cuesta”.

Furthermore, deep into the quarry, one may find the contact between rocks of Phra Wihan Formation and the underlying Phu Kradueng Formation.

Dinosaur Footprint

40

Dinosaur Footprint:

Traces of Ancient Animals in the Centre of the Forest A group of nature explorers came into this tropical forest a long time ago in hope to find new plant species or rare wild animals. However, what they found was even more miraculous than expected as it turned out to be the important clue to let us know that Khao Yai National Park used to be the habitat area of dinosaurs more than 65 million years ago.

Flowing through the valley in Nadi District, Prachinburi Province, Lam Nam Sai Yai has cut through and eroded rock layers creating a series of high cliff, approximately 40 meters high. Large sandstone pieces that tumbled down and distributed along the water course and on both banks of the river.

Over the southern bank of the river, there are three pieces of sandstone with evidence indicating that this area used to be dinosaurs’ habitat.

On the surface of these white to reddish-brown sandstone pieces, interbedded with a thin layer of gravel, exhibits a large cast of dinosaur’s footprint, many casts of small footprints, along with ripple marks.

Based on the characteristic of the flatness of the foot and the three fingers found, paleontologists have pointed out that the footprint belongs to the meat-eating theropods of both large and small sizes.

These dinosaurs walked on their two powerful hindlimbs or hindlegs, with their heads pointed to the front, balancing its bodies using the straight tail that pointed backward. Their two forelimps or forearms were used for hunting its preys. The dinosaur has later been named as “Siamopodus khaoyaiensis” (Lockley et al., 2006) to honour the place where the dinosaur fossil was firstly discovered.

• There are a long number of dinosaurs’ footprints occurred on the ripple marks.

This is a clear evidence indicating that there were large and small dinosaurs walked on clayey sand sediments along the bank of the slow flowing stream.

Later, a number of geologists from various offices have studied the dinosaurs’ footprints of Khao Yai and agreed that this dinosaur existed during the Early Cretaceous or approximately 140 million years ago.

Even though the rock pieces that display the footprints are assigned to be of Khorat Group, the stratigraphic correlation based on rock formation of these rock pieces are still somewhat questionable due to the fact that these rock pieces are floated materials.

41

Dinosaur Footprint

Rock Piece 1: It displays one large dinosaur footprint with 27 centimeters wide and 31 centimeters long. Another seven footprints are small sizes with 11 centimeters wide and 17 centimeters long.

Rock Piece 2: This piece of rock is located further up the bank slope with its base faces up showing a number of small dinosaur footprints that have been eroded and not clearly displayed.

Rock Piece 3: It is the large piece of rock found along the bank of the stream with its base faced up and oriented with the dipping of approximately 80 degrees.

The surface of this rock displays three footprints along with a clear evidence of ripple marks.

• Footprints, marks, tracks, burrows, eggs and nests are trace fossils because they are not actually the remains of the organism itself, i.e., skeleton and bones, but rather reveal more about lifestyle and habits of those living things.

When dinosaurs walked along the banks of slow flowing waterway leaving its footsteps to form mold over the ripple marks on the clayey sand bed.

Later, some sediments deposited over those molds.

The process continued for millions of years, those sediments were then lithified to form rock. Later, when the rock beds were uplifted to the Earth’s surface and eroded along the beding plane, it reveals footprints traces on the rock’s surface and the casts of dinosaurs on the bedding surface of the upper rock bed.

Investigation from Rock, Soil and Sand

42

CHAPTER 4 Investigation from Rock, Soil and Sand The Geologist’s Work

“Geologist” is a person who can interpret geological clues in rocks and various types of landforms through the investigation on rock, soil and sand and the interpretation though the application of geological principles to solve the amazing past, present and future of the Earth.

With the efforts to understand the nature of the Earth, geologists study rocks of various types that constitute the Earth’s crust. These rocks are similar to the documents that record the story of the past events. The study involves works in the field and the laboratory. Then

43

identify rocks and minerals, a field note, as well as necessary stationery, rock and mineral identification toolkit, camping gears, foodstuffs, field assistants, and most importantly, experience, would start their survey, investigate and search for evidence in the study area to check out their hypothesis.

After the fieldwork, geologists carry all rock, mineral and fossil samples, including information noted, back to the office or to analyze through scientific process in the laboratory to achieve vital data that will be compiled to reach the conclusion at the end of the study.

Nowadays, “Geology” becomes widely involves with our lives, such as: the exploration for minerals to be used to sustain lives and to be consumed in an increasing quantity; the prevention and mitigation of dangers from geohazard events; the planning on soil development that has impacts on the environment; the searching on the evolution of life, and the national development planning.

Investigation from Rock, Soil and Sand

gather the data achieved to be analyzed, interpreted and summarized.

Before getting into the field, geologists always try to familiarize with the area through the study of topographic and geological maps of various scales; study of previous survey reports in order to have some guidelines for the follow-up survey; interpret the aerial photographs and satellite imagery in order to study the topography, rock types, geological structures and other relevant information; then compile all the data to create the preliminary geological map of the area that will be very useful for the speed up of the geological survey of the study area.

During the dry season, in the winter and summer times, many trees shed its leaves, the dense forest turns sparse unfolding many outcrops. Geologists, equipped with all indispensable geological tools including topographic maps, a field compass, a geological hammer for breaking the rock pieces, a magnifying glass or hand lens to

Geological Survey Report of Khao Yai National Park

44

Geological Survey Report of Khao Yai National Park Khao Yai National Park covers an area of 2,168.74 square kilometers. It is located in a 1:50,000 scaled topographic maps of the Royal Thai Survey Department sheets: Amphoe Pakchong (5238II), Amphoe Kaeng Khoi (5238 III); Ban Salika (5237 I); Changwat Prachinburi (5237 II); Amphoe Ban Na (5237 IV); Ban Sabbon (5337 I); Ban Thung Pho (5337 II); Amphoe Prachantakham (5337 III) and Ban Tha E-Som (5337 IV). The area is also located in the 1:250,000 scaled geological map of Changwat Phra Nakhon Si Ayutthaya, which was surveyed

by Chaiyan Hinthong et al. (2524).

Khao Yai National Park is underlain with Permian rocks of Saraburi Group, which is the oldest rock unit in the area, unconformably overlain with rocks of the Mesozoic Era or the Khorat Group.

Geology of Khao Yai National Park and Its Vicinity

Khao Yai National Park area comprises rocks of different ages ranging from Permian to Cretaceous times. Over 50 percent of the area is underlain by rocks of the Khorat Group and Saraburi Group. The rest of the area is covered with volcanic rocks.

Rocks of Saraburi Group: Rocks of Saraburi Group of Permian age are the oldest rocks of the area comprising marine sedimentary rocks. The rock group is divided into 6 rock formations, only two of these were found within the national park, i.e., Khao Khad and Sabbon Formations.

• Khao Khad Formation: Rocks of this formation were reported located to the north of the national park area and can be seen from the Scenic View Point at Km. 30. The area exhibits karst topography with a number of high mountain ridges where caves with stalactite and stalagmite were always reported, e.g., around Khao Luk Chang and Khao Tham Din. The rock unit comprises white- to dark-grey limestone, with thin to thick beds, interbedded with some chert layers and intruded by volcanic rocks in some of the area. Fossils found within this rock unit include small organisms, i.e., fusulinids, corals, crinoids, nautiloids, and brachiopods.

These fossils indicate that this limestone unit deposited in shallow sea approximately 250-240 million years ago.

45

Khorat Group Rocks of Khorat Group are sedimentary rocks deposited from stream sediments approximately 180 - 65 million years ago.

According to the Department of Mineral Resources, rocks of Khorat Group can be divided into nine formations, namely, from bottom to top, Huai Hin Lat Formation, Nam Phong Formation; Phu Kradueng Formation, Phra Wihan Formation, Sao Khua Formation, Phu Phan Formation, Khok Kruat Formation, Maha Sarakham Formation, and finally, Phu Thok Formation at the top. There are only Khorat Group found within the national park detailing as follow: • Phu Kradueng Formation: This rock unit comprises micaceous siltstone interbedded with fine-grained, reddish-brown and greenish-grey, micaceous sandstone. According to the texture and structure within the rock beds, it indicates that rocks of Phu Kradueng Formation were deposited under the meandering stream system in the semi-arid type of weather approximately 140 - 150 million years ago (Late Jurassic time).

The outcrop is spotted as small hills, e.g., round the scenic view point located to the west of the camping ground of Pha Kluay Mai Waterfall.

• Phra Wihan Formation: These rocks distribute over the eastern part of the national park, usually formed as butte, e.g., Khao Khiew, Khao Kamphaeng, Khao Rom and Khao Samo Pun. Most of the rocks comprise medium-to-coarsegrained quartzitic sandstone, white, pale brown, yellowish brown, well sorted, with cross-beddings that show flow directions of paleo-current indicating that these rocks were deposited under the braided stream environment approximately 120 - 130 million years ago.

• Khao Yai Volcanic Complex Rock Group: There are various types of extrusive rocks or volcanic rocks found in Khao Yai National Park, e.g., rhyolite, andesite, volcanic agglomerate and volcanic tuff. Generally, within a particular area, it is possible to find more than two rock types that can hardly be identified, thus referred to as “Khao Yai Volcanic Complex Rock Group”. This rock unit was found distributed over the northern and western parts of the national park, i.e., Khao Nong Ma Kor, Khao Fa Lami, Khao Inthani, Khao Khlong Phai, Khao Kaew, Khao Salika, Khao Tabaek, Khao Pa Por, and Khao Takrut.

• Rhyolite: Rhyolite was mostly found around the lower part of Hew Suwat Waterfall, Hew Narok Waterfall, Pha Kluay Mai Waterfall and around the mountain area located to the western part of the national park. In the area around Pha Kluay Mai Waterfall, the rhyolite outcrop clearly reveals its flow direction. Rhyolite of the area is pale white and purplish pink, fine-grained with some quartz and feldspar phenocrysts. Some calcite (pale-green) and sericite (yellowish brown) grains were also presented in the rock.

• Andesite: the rock was found around the southern part of the national park, especially in the area of Nakhon Nayok Province. The rock is fine-grained, grayish green to grey, and consisted of feldspar, quartz and hornblende.

Tuffaceous andesite was also cropped out on the Hew Suwat Waterfall area.

• Volcanic Agglomerate: the volcanic agglomerate is a clear evidence of violently explosive volcanism in the past. The rock is found narrowly distributed in small area, e.g., the upper part of Hew Suwat Waterfall.

• Volcanic Tuff: the rock was exposed around the northern and eastern parts of the national park, e.g., Surasawadi Youth Camp Area and the Scenic View Point Km. 18. It is coarsegrained, usually purple and reddish brown.

Structural Geology There are several types of geological structures found within the national park including many folding and faulting. These structures indicate the violent past movement of the Earth’s crust, especially during the PermoTriassic, resulted in change and deformationin the old rock sequences.

Geological Survey Report of Khao Yai National Park

• Sabbon Formation: Rocks of this formation exposed over the northern part of the national park with topography of rolling hill around the foothills located to the south of Ban Tha E-Som. The rocks comprise: shale interbedded with siltstone and sandstone, yellowish-brown to pale brown; interbedded with thin to thick layered of grey to dark grey limestone, with some chert nodules. Rocks in some places were metamorphosed to form phyllite.

Fossils found in this rock formation include small organisms of fusulinids and nautiloids, indicating the deposition environment of shallow sea, similar that of to the Khao Khad Formation.

Nature Will Live on Forever

46

CHAPTER 5 Nature Will Live on Forever

“Ecotourism”: the Sustainable Use of Khao Yai National Park Area It took nature millions of years to create water and land that used to be hot to become a fertile piece of green and valuable forest, namely “Khao Yai”, that Thai people are proud of. It would be rather unfortunate if the beloved world’s natural heritage that should be handed over to the next generation would have come to an end due to the lacks of awareness.

47 Nature Will Live on Forever

The work of natural creation, equipped with its charm of beautiful landscapes, yearround cool temperature, healthy ecosystem, and biodiversity of both wild plants and animals, have made this piece of forest invaluable for a long time. At present, Khao Yai National Park has turned to be the popular and important tourists’ site and nature study site that create great amount of income from tourism to both local community and the country.

Human beings who are gifted in making use of natural resources with the appreciation of what the nature has done for them would always want to pay back with an understanding of the creating process of many natural resources. This would help to sustain the use of nature. However, the reverse is true in reality. Even though, Khao Yai National Park is one of the World Heritage, it is still unavoidably facing the problems on deterioration of natural resources due to human’s activities such as deforestation, hunting, invasion of protected area, as well as destroying the natural elements of landscapes in the tourism sites without any awareness that may have resulted in an end to this Khao Yai forest.

“Ecotourism” or “Sustainable Tourism” is another alternative to conserve this World Heritage forest. Under the up-to-date concept on the development and make use of the area that “the development that can respond to the present needs of tourists and the local communities through the protection and

conservation for the opportunity to access to the resource of the next generation to come”. To make this conservation path successful, there must be the integration among related organizations and persons that are responsible for the management of the area; issuing management pattern based on proper technical knowledge; and people or tourists who travel for pleasure with an understanding of the value of these natural resources. The ecotourists would go out there to take pictures, learn and be filled with the contentment on the beauty of the nature, leaving behind only footsteps on the ground in stead of their names or words that carved on rock surfaces that would ruin and rid of the charming of all landscapes.

What Does Khao Yai Give Us…?

“What does Khao Yai give us?” is a big question. Similarly, the question: “What does nature give human?” would be too difficult to answer it all, due to the fact that human beings must rely on nature before building up their own civilization.

“Khao Yai”, a fertile piece of forest, is like the origin of life. This forest is an important study site that tells us how great the nature is.

Khao Yai National Park is the work of nature that takes hundreds of million years to carve from wide sea to form continental plate. Stream and wind eroded big mountain down to small sized gravels and sands that were then transported and deposited to form soil. At the same time, early organisms like mosses and lichens began to digest and root at the beginning of plant evolution. It takes a very long period of time for living things to evolve and become a fertile forest piece of Khao Yai, which is the valuable source of natural resources, such as, mountains, streams, waterfalls, forest, rare plants and animals. This natural archive that recorded the evolution of the Earth is very valuable to the research studies making the forest a study site and a beautiful recreational and rest area.

This World Heritage belongs to everyone who can access and make use of

it to suit their purposes, e.g., research and study, recreation, etc. All the things

that form Khao Yai National Park including the topography and ecosystem are all

related as a big system. If any of the small parts were completely destroyed, it

would be difficult for the whole forest to continue its existence. We have always

taken from nature for a very long time. It is time to ask oneself on what we have

ever given back to the nature. The answer may help Khao Yai National Park to continue its existence for the benefit of the next generations to come.

(Mrs. Pornthip Puncharoen)

Director General Department of Mineral Resources

49

Glossary of Geology mainly of quartz microcrystals with various colours, e.g., gray, red and brown. It may also contain some organisms.

Continental crust = The type of the Earth’s crust which underlies the continents and the continental shelves and ranges in thickness from about 35 km to as much as 60 km under mountain ranges.

Continental plate = Landmasses that comprises the Earth’s crust and the upper part of the upper mantle that were broken up to form continents and drifted by the magmadriven convection cell within the Earth.

Continental shelf = That part of the continental margin that is between the shoreline and the continental slope with a very gentle slope of 0.1 degree.

Continental slope = That part of the continental margin that is between the continental shelf and the continental rise. It is characterized by its relatively steep slope of 1.5 - 6 degrees and the depth between 200 - 3,600 meters.

Convection current = A heat transfer phenomenon. In plate

tectonics, it refers to the movement of molten rock mass in

the mantle that moved from the inner part, that is hotter,

to the outer part, that is cooler, due to heat transfer from

the inside of the Earth.

Cross bedding = Geological layers formed at angle: layers

of geological strata in which deposits were laid down at an

angle with respect to those above and below due to the

changing directions of water or wind resulting in the dipping

of layers towards the flow direction.

Crust = The outermost shell of the Earth with an average

depths between 6 - 35 km and made up of two layers: the

granitic upper part or sial and the intermediate mafic or sima.

Cuesta = A hill or ridge with a gentle slope on one side

and a steep stope on the other.

Dip = The angle that a structural surface makes with the

horizontal, measured perpendicular to the strike of the

structure and in the vertical plane.

Escarpment = A long and continuous cliff or relatively steep

slope facing in one general direction, breaking the continuity

of the land by separating two level or gently sloping surfaces,

and produced by erosion or by faulting. A cliff formed by

differential erosion.

Evaporite = A non clastic sedimentary rock composed mainly

of minerals produced from a saline solution as a result of

extensive or total evaporation of the solvent. Most minerals

include rocksalt (halite), gypsum, and anhydrite.

Fault = A fracture or a zone of fractures along which there

has been displacement of the sides relative to one another

parallel to the fracture.

Flood plain = The surface of relatively smooth land adjacent to

a river channel, constructed by the present river in its existing

regimen and covered with water when the river overflows

its banks during the rainy season.

Flow bands = One of the structural pattern in volcanic rock

that formed from the crystallization of lava with the orientation into the flow layers or bands while it was still hot and flowing.

Fluvial = Said of or pertaining to a river or rivers; produced

by the action of a stream or river.

Fluvial plain deposit = A sedimentary deposit consisting of

material transported and laid down by a stream.

Footprint = A type of structural trace fossils that occur in the

rock indicating the habitat environment of the living things

in the past.

Fracture = A general term for any break in a rock, whether

or not it causes displacement. Fracture includes cracks,

joints and faults.

Fusulinid = Any foraminifer belonging to the suborder Fusulinina characterized by a multichambered elongate calcareous microgranular test, commonly resembling the shape of a grain of rice.

Geologist = A person who works on geology.

Geology = The science that examines the Earth as a whole, its origin, its form, the materials of which it is made, the processes that act on these materials and make it to change, the history of the planet and its life forms since its origin.

Gondwana = The very large Late Paleozoic continent that used to be located in the Southern Hemisphere. It later moved up and disintegrated to form African Plate, Indian Plate, part of Australia and Thailand.

Graded bedding = A type of bedding in which each layer displays a gradual and progressive change in particle size, usually from coarse at the base of the bed to fine at the top.

Ignimbrite = A type of volcanic rocks formed by the widespread deposition and consolidation of ash flows and nuée ardentes (swiftly flowing volcanic gaseous cloud) Iridium = An element of the platinum group, symbol Ir, with an atomic number of 77. It is a transition element, silver white, very hard and heavy but brittle, used in making alloy. It is one of the elements of a mineral found in meteor.

Island arc = (or volcanic arc) A generally curved linear belt of volcanoes or volcanic islands above subduction zone.

Joint = A surface of fracture or parting in rocks, without displacement. The surface is usually planar and often occurs in various sets of fracture planes indicating force direction that applied to the rocks.

Landform = Any physical, recognizable form or feature of the Earth’s surface, having a characteristic shape, and produced by natural causes. It includes major forms such as plain, plateau, and mountain. The study on the land form is referred to as “Geomorphology”.

Lapilli = Pyroclastics that may be either essential, accessory, or accidental in origin, of a size range that has been variously defined within the limits of 2 and 64 mm. The fragments may be either solidified or still viscous when they land, thus there is no characteristic shape. The pyroclastic that is larger than 64 mm is called “volcanic block”.

Lava = A general term for a molten extrusive (being pushed up to the Earth’s surface).

Lithosphere = The solid portion of the Earth. It is a layer of strength relative to the underlying asthenosphere for deformation at geologic rates. It includes the crust and part of the upper mantle.

Glossary of Geology

Accretion = 1. Process by which an inorganic body grows

in size by the addition of new particles to its exterior. 2. The

increase in size of island arc or the addition of materials

to the edge of a continent due to plates convergence or

collision.

Agglomerate = volcanic breccia: A pyroclastic rock that

consists of angular volcanic fragments that may or may not

have a matrix.

Ammonite = Any ammonoid belonging to the order

Ammonitida, characterized by a thick, strongly ornamented

shell with sutures having finely divided lobes and saddles.

Ammonoid can be roughly divided into goniatite, ceratite

and ammonite. Ammonite can be used as an index fossil to

tell the age of the rock.

Andesite = A dark-coloured, fine-grained extrusive rock that

mainly contains calcic-plagioclase and pyroxene.

Ape = Any of various large, tailless or short tail, old world

primates.

Ash-flow tuff = A tuff deposited by an ash flow or gaseous

cloud that violently exploded from the volcanic vent

breaking the lava around the vent to small pieces (less

than 2 millimeters); a type of ignimbrite. It is a consolidated

by not necessarily welded deposit.

Asthenosphere = The layer or shell of the Earth below the lithosphere which is weak and in which isostatic adjustments take place, magmas may be generated, and seismic waves are strongly attenuated. It is a part of the upper mantle around the depths from 100 - 350 km from the Earth’s surface.

Basalt = An extrusive rocks with fine-grained, dark-coloured,

grey to dark grey, composed chiefly of calcic-plagioclase

and clinopyroxene. Secondary minerals include apatite and

magnetite.

Base level = The theoretical limit or lowest level toward

which erosion of the Earth’s surface constantly progresses

but seldom reaches, especially the level below which a

stream cannot erode its bed.

Bedding plane = A planar or bedding surface that visibly

separates each successive layer of stratified rock from the

preceding or following layer.

Brachiopod = Any solitary marine invertebrate characterized

by a lophophore and by two bilaterally symmetrical valves

that are commonly attached to a substratum but may also

be free. Range: Cambrian to present.

Braided stream = A stream that divides into or follows an

interlacing or tangled network of several small branching

and reuniting shallow channels separated from each other

by branch islands or channel bars, resembling in plan the

strands of a complex braid.

Butte = A small mountain with relative steep slopes and a

flat-top cap of resistant layer caused by differential erosion

of gently-dip rock layers.

Cast = Sedimentary rock or mineral material that fills a

natural mold creating a replica or a reproduction of the

external details of a fossil.

Chert = A hard, extremely dense sedimentary rock consisting

Glossary of Geology

50 Lower mantle = The part of the mantle that lies below the mohorovicic discontinuity and above the Wiechert - Gutenberg discontinuity or a depth of about 1000 km to 2900 km with ultramafic composition that has a density of 4.7 g/cm3, in which the seismic velocity increases slowly with depth.

Magma = A body of molten rock generated within the Earth and capable of intrusion and extrusion. It may or may not contain suspended solids (such as crystals and rock fragments) and gas phase.

Meandering stream = Bending stream courses that is similar to the strand of ropes. It is usually found with the river running along the flat plain where the vertical erosion is less than the horizontal one. The moving water in a river erodes the outer banks and widens its valley, and at the same time, deposits the sediments on the inner banks.

Mesa = An isolated table-land area with steep sides, the result of a horizontal capping of hard strata having resisted denudation.

In the course of time with continual erosion of the sides a mesa is reduced to a smaller flat-toped hill, a butte.

Modern man = Homo Sapiens, with intelligence, with important characteristics of verbal and written communication, able to invent tools for their livings.

Mold = An impression made in the surrounding earth or rock material by the exterior or interior of a fossil shell or other organic structure.

Mudstone = Fined-grained detrital sedimentary rock with generally equal proportion of clay and silt particles. The sediment sizes range from 0.3 - 2.0 mm.

Neogene = the name given to the Miocene and Pliocene periods of the Tertiary, covering the time from 23 to 2.6 million years ago.

Oceanic plate = It is the part of Earth’s lithosphere that surfaces in the ocean basins that comprises the Earth’s crust and the upper part of the upper mantle that were broken up to form the ocean floor and drifted by the magma-driven convection cell within the Earth.

Oceanic ridge = A continuous, seismic, median mountain range.

It is 1-3 km in elevation, about 1500 km in width, and over 48000 km in length. According to the hypothesis of sea-floor spreading, the mid-oceanic ridge is the source of new crustal material. The new plates gradually move from both sides of the ridge and subduct along the submarine trench.

Paleogene = An interval of geologic time incorporating the Paleocene, Eocene and Oligocene of the Tertiary referring to the age from 65 - 23 million years ago.

Plate = (Lithospheric Plate) Under the plate tectonic theory, a plate is a layer of the Earth’s materials that comprises the Earth’s crust and the upper part of mantle. It is relatively a rigid layer compared to the lower mantle underneath that can move horizontally in various ways along the plate’s boundary.

Plateau = A flat, upland region characterized by horizontal structure with at least one side abruptly dipping toward the lower ground.

Plate tectonic = A theory of global tectonics in which the lithosphere is divided into a number of plates whose pattern or horizontal movement is that of torsionally rigid bodies that interact with one another at their boundaries, causing seismic

and tectonic activity along these boundaries.

Pothole = A smooth bowl-shaped or cylindrical hollow usually with gravel and coarse sand deposited at the bottom, formed in the rocky bed of a stream by the grinding action of stones or coarse sediment, whirled around and kept in motion by eddies or the force of the stream current to form various sizes of holes.

Pyroclastics = Volcanic rock fragments, minerals and volcanic glasses of various sizes that formed from the falling down (from volcanic explosion) directly form the air; washed down by water; and blown and dropped by wind, to accumulate in the nearby area.

Pyroclastic rock = Pyroclastic rocks consist of mixed fragmental volcanic material which has been blown into the atmosphere by explosive activity. These materials include rock fragments, minerals and volcanic ashes of different sizes.

Radiolaria = Marine planktonic animals, in which a central capsule and surrounding spicules consist of silica. They are found only in the deep part of the ocean in tropical area.

Rapids = A part of a stream where the current is moving with a greater swiftness than usual and where the water surface is broken by obstructions but without a sufficient break in slope to form a waterfall, as where the water descends over a series of small steps. It commonly results from a sudden steepening of the stream gradient, from the presence of a restricted channel, or from the unequal resistance of the successive rocks traversed by the stream.

Rhyolite = A group of extrusive igneous rocks, typically porphyritic and commonly exhibiting flow texture, with phenocrysts of quartz and alkali feldspar in a glassy to cryptocrystalline groundmass, the extrusive equivalent of granite.

Ripple mark = An undulatory surface or surface sculpture consisting of alternating subparallel small-scale ridges and hollows formed at the interface between a fluid and incoherent sedimentary material. It is produced on land by wind action and subaqueously by currents or by the agitation of water in wave action, and generally trends at right angles or obliquely to the direction of flow of the moving fluid.

Rock salt = Coarsely crystalline halite (sodium chloride: NaCl) occurring as a massive, fibrous, or granular aggregate and constituting a nearly pure sedimentary rock. In Thailand, rock salt is abundant in the northeastern part, i.e., in Sakon Nakhon and Khorat Basins.

Salt lake = An inland body of water situated in an arid or semiarid region, having no outlet to the sea, and containing a high concentration of dissolved salts (principally sodium chloride).

Shale = A fine-grained detrital sedimentary rock, formed by the consolidation or compression of clay, silt or mud. It is characterized by finely laminated structure, which imparts a fissility approximately parallel to the bedding, along which the rock break readily into thin layers and that is commonly most conspicuous on weathered surfaces, and by a appreciable content of clay minerals and detrital quartz.

Siltstone = A clastic sedimentary rock having the texture and composition of shale but lacking its fine lamination or fissility.

It is a massive mudstone in which the silt predominates over

clay, in other word, a nonfissile silt shale.

Sorting = The dynamic process by which sedimentary particles having some particular characteristic such as similarity of size, shape, or specific gravity, that are naturally selected and separated from associated but dissimilar particles by the agents of transportation.

Subduction = The process of one lithospheric plate descending beneath another along subduction zone, which is a long, narrow belt.

Suture zone = An area along the convergent lithospheric plate boundary.

Tectonics = Said of or pertaining to the forces involved in, or the resulting structures, or features of, tectonics.

Theropods = The meat-eating or carnivore dinosaur that walked on two hind limbs, with two short fore limbs.

Topographic map = A map showing the topographic features of a land surface, commonly by means of contour lines.

Trench = A narrow, elongate depression of the deep sea floor, with steep sides, oriented parallel to the trend of the continent and between the continental margin and the abyssal hill. Such a trench is about 2 km deeper than the surrounding ocean floor, and may be thousands of kilometers long.

Triangular facet = Cliffs that formed as a result of vertical movement along fault plane that cut through mountain ridge, then eroded by streams that run along ridges to form this triangular facet cliff.

Tuff = A general term for all consolidated pyroclastic rocks that are generally consist of volcanic gases and ashes that violently exploded, deposited and cool to form tuff.

Turbidite = A sediment or rock deposited from, or inferred to have been deposited from, a turbidity current. It is characterized by graded bedding, moderate sorting and well-developed primary structures in the sequence.

Uplift = A structurally high area in the crust, produced by positive movements that raise or upthrust the rocks.

Upper mantle = The part of the mantle which lies below the Earth’s crust, approximately 35 km over continent and 10 km over the ocean, and lies above a depth of about 1000 km with a density of 3.40 g/cm3, in which P-wave velocity increases from about 8 to 11 km/sec with depth and S-wave velocity increases from about 4.5 to 6 km/sec with depth.

Volcanic arc = A generally curved linear belt of volcanoes above a subduction zone, and the volcanic and plutonic rocks formed there.

Volcanic ash = Fine pyroclastic material (under 2.0 mm diameter; under 0.063 mm diameter for fine ash). The term usually refers to the unconsolidated material but is sometimes also used for its consolidated counterpart, tuff.

Volcanic rock = Rocks formed from volcanic explosion, either rejected explosively or extruded as lava at or near the Earth’s surface, generally finely crystalline or glassy. Volcanic rocks can be classified into various types depend on its composition and how it forms.

Bibliography

51

Thai Asavachaichan, S. and Krairotchananan, P. Guidebook Series for Park Trip: Khao Yai National Park. Bangkok: Sarakadee, 2000.

Department of Mineral Resources. Biodiversity of the Ancient Lives in Thailand, A Special Publication on the Occasion of 114th Anniversary of the Department of Mineral Resources, 1 January 2006. Bangkok: n.p., 2006.

Department of Mineral Resources. Geology of Thailand, The Celebration for H.M. the King, A Special Publication for the Celebration on the Auspicious Occasion of His Majesty the King’s 6th Cycle Birthday Anniversary 5 December 1999. Bangkok: Ministry of Industry, 2001.

Foundation of Khao Yai National Park, Guide Book on 5 Nature Trails of Khao Yai National Park. Bangkok: Plan Printing Co., Ltd., 2001.

Imsamut, S. A Study Report on Stratigraphy and Texture of Rocks of Sao Khua Formation, Khao Kamphaeng Area, East Khao Yai National Park. Department of Mineral Resources, 1997.

National Geographic. National Geographic Special Issue, Origin of Life on Earth. Bangkok: National Geographic, 2004.

Srikosamatara, S. and Hansel T. improved by W. Dougworth and A. Lynam. Mammals of Khao Yai National Park. 3rd ed. Bangkok: Green World Foundation, 2004.

Suphachanya T. [et al.]. Thai-English Picture Dictionary, Our World. Bangkok: River Books, 1996.

Tansathien, W. Manual for a Workshop on the Development and Promotion of Department of Mineral Resources’ Legal Aspects on Basic Knowledge on Fossils. Bangkok: n.d.

English Bates, Rk., and Jackson, J.A. Glossary of Geology. 3rd ed. Virginia: American Geological Institute, 1987.

Chandler, Fiona, Sam Taplin and Jane Bingham. Prehistoric World. Bangkok: Osborne, 2005.

Osborne, Roger, Donald Tarling and Stephen Jay Gould. The Historical Atlas of the Earth.

Great Britain: Henry Holt, 1996.

Bibliography

Bureau of Fossil Study and Museums. Dinosaurs of Thailand. Bangkok: Department of Mineral Resources. 2007.

A GEOLOGICAL JOURNEY: KHAO YAI NATIONAL PARK THE WONDER OF THE WORLD HERITAGE Publisher Department of Mineral Resources 75/10 Rama VI Road, Ratchathewi, Bangkok 10400 Tel. 66 (0) 2621 - 9500 Website: www.dmr.go.th

International Standard Book Number (ISBN) 978-974-226-462-8 First Edition September 2010, 500 copies Thankful and appreciation to the following offices Director General of Department of National Parks, Wildlife and Plant Conservation Khao Yai National Park, Department of National Parks, Wildlife and Plant Conservation

Committee Dr. Pol Chaodumrong Mr. Lertsin Raksakulwong Mr. Wattana Tansathien Dr. Somboon Khositanont Mr. Terapon Wongprayoon Mr. Suvapak Imsamut Mr. Pracha Kuttikul Mr. Kamol Boonnum Mr. Rath Jitrattana Ms. Darunee Jenjai

Advisory Group Dr. Varavudh Suteethorn Mr. Phitaks Ratanajaruraks Dr. Dhiti Tulyatid Mr. Surachai Siripongsatian Mrs. Yaowalak Chaimanee Mr. Boonroong Suangarmiam Mr. Somchai Khieowruangngam Ms. Sasidhorn Khansubha Mr. Sakchai Juanngam Writer and Technical Advisor Mr. Sin Sinsakul Writer Mr. Sirot Salyapongse Advisor Geological Period Illustration Mr. Chotiwat Punnopatham Designed by Amarin Publishing Services Amarin Printing and Publishing Public Company Limited 65/16 Chaiyaphruk Road, Taling Chan, Bangkok 10170 Tel. 66 (0) 2422 - 9000 Ext. 1200, 1213 Fax. 66 (0) 2422 - 9091

Colour Separation and Printed by Printing Business Division Amarin Printing and Publishing Public Company Limited 65/16 Chaiyaphruk Road, Taling Chan, Bangkok 10170 Tel. 66 (0) 2422 - 9000, 66 (0) 2882 - 1010 Fax. 66 (0) 2433 - 2742, 66 (0) 2434 - 1385 Text and images in this book are copyrighted by Department of Mineral Resources. If used, whether some or all must get permission from Department of Mineral Resources.

“Mankind has the highest potential in protecting the nature” Department of Mineral Resources 2010

กรมทรัพยากรธรณี ถนนพระรามที่ 6 เขตราชเทวี กรุงเทพฯ 10400