Earthquakes

Earthquakes and Volcanoes 1. Before the earthquake

After the earthquake

Location: Stanford University, San Francisco, United States Date of Occurrence: April 18th, 1906 Magnitude: 8.3 2.

3.

UTC DATE-TIME y/m/d h:m:s MAP 2.5 2007/12/06 02:41:13 MAG

LAT LON DEPTH Region deg deg km 60.056 -153.085 100.0 SOUTHERN ALASKA

MAP 5.1 2007/12/06 01:11:18 -23.120

-70.352

MAP 3.4 2007/12/06 00:10:24

52.987 -168.793

MAP 3.5 2007/12/06 00:10:23

52.876 -168.622

MAP 5.0 2007/12/06 00:10:16

54.638

160.296

UTC DATE-TIME LAT LON y/m/d h:m:s deg deg MAP 2.5 2007/12/05 22:05:45 61.506 -149.795 MAG

MAP 2.8 2007/12/05 21:40:36 39.615 -121.827 MAP 2.7 2007/12/05 15:21:06 61.278 -151.256 MAP 2.8 2007/12/05 13:09:35 32.148 -115.914 MAP 5.1 2007/12/05 12:55:04

-5.603

148.458

MAP 5.4 2007/12/05 12:11:23 15.041

-61.315

MAP 2.6 2007/12/05 11:36:49 60.615 -151.729 MAP 3.0 2007/12/05 10:49:28 40.023 -121.161 MAP 2.5 2007/12/05 07:02:51 32.752 -115.541 MAP 5.1 2007/12/05 04:33:39 25.893

124.167

MAP 4.7 2007/12/05 03:14:55 30.054 70.148 MAP 4.9 2007/12/05 01:41:41 22.991 121.387 MAP 3.4 2007/12/05 00:22:42 36.429 -113.182

ANTOFAGASTA, CHILE FOX ISLANDS, 57.3 ALEUTIAN ISLANDS, ALASKA FOX ISLANDS, 49.1 ALEUTIAN ISLANDS, ALASKA NEAR THE EAST COAST OF 113.5 KAMCHATKA, RUSSIA DEPTH Region km 50.4 SOUTHERN ALASKA NORTHERN 2.4 CALIFORNIA 63.7 SOUTHERN ALASKA BAJA CALIFORNIA, 6.5 MEXICO NEW BRITAIN 186.3 REGION, PAPUA NEW GUINEA DOMINICA REGION, 162.7 LEEWARD ISLANDS KENAI PENINSULA, 50.7 ALASKA NORTHERN 0.0 CALIFORNIA SOUTHERN 14.7 CALIFORNIA 66.8

184.4

* NORTHEAST OF

TAIWAN 7.0 PAKISTAN 5.3 *TAIWAN REGION 5.0 ARIZONA

Symbols * Earthquakes nearest to Kunming 4. A. Place of Volcanic Eruption: Arenal, Costa Rica Location: 10.46N, 84.70W Erupted in February 06, 2006 and ongoing throughout 2007

B. Place of Eruption: Karymsky, Kamchatka Peninsula, Russia Location: 54.0N, 159.5E Erupted in December 14, 2004 and ongoing in 2007 C. Place of Eruption: Kilauea Volcano, Hawaii, United States Location: 19.452 N, 155.292 W Erupted in November 30, 2004 and ongoing in 2007 D. Place of Eruption: Rabaul Caldera, Papua New Guinea Location: 4.27 S, 152.20 E Erupted in February 05, 2005 and ongoing 2007 5.

Place of Eruption: Rabaul Caldera, Papua New Guinea Type of Volcano: Active Location: 4.27 S, 152.20 E Elevation: 688 m (2,257 feet) Last Updated: February 05, 2005

Sangay, Ecuador Type of Volcano: Active Location: 78.3W, 2.0S Elevation: 17,154 feet (5,230 m) Last Updated: February 13, 2004

6.

Symbols ^ Earthquakes

+ Volcanoes 7. Recent Earthquake Posted : Mon, 26 Nov 2007 02:50:04 GMT Author : DPA Category : Asia (World) Jakarta - Strong earthquakes struck off the eastern Indonesian island of Sumbawa early Monday, killing at least two people and injuring more than 40 others, seismologists and officials said. One quake, measuring 6.7 on the Richter scale struck 50 kilometres north-west of the Raba district town on Sumbawa island in West Nusa Tenggara at 12:02 am (1602 GMT Sunday), Indonesia's Meteorology and Geophysics Agency (BMG) reported. It occurred at about 50 kilometres beneath the seabed.

A 6.8-magnitude aftershock took place about two hours later, adding to the damage of homes and buildings as well panicking residents who had fled their homes after the initial quake, officials and residents said.

According to reports from the scene two people were killed and 45 others were injured, said Rustam Pakaya, chief of the Health Ministry's Crisis Centre.

He said one of the deaths was a 5-year-old boy, while scores of homes and buildings were badly damaged by the quakes, the latest in series of shocks to strike in Indonesia in recent days.

Suriyani, an official at the general hospital in Dompu district on Sumbawa, said that the hospital was treating around 20 injured people, adding that most of them had been wounded from collapsing walls.

An official at BMG in Jakarta said a tsunami warning was issued but lifted later after no tidal waves took place.

The quakes were also felt on the nearby islands of Lombok and Bali.

Another 6.0-magnitude quake hit off the western coast of West Sumatra early Monday, but there were no reports of casualties or damage.

The Indonesian archipelago sits on the so-called "Pacific Ring of Fire," where continental plates meet and cause frequent seismic and volcanic activity.

Indonesia was the nation worst hit by the earthquake-triggered Asian tsunami in December 2004, which left more than 170,000 people dead or missing in Aceh province alone.

Copyright, Earthtimes

Recent Volcano Posted : Sun, 02 Dec 2007 00:21:04 GMT Author : DPA Category : Environment

Mexico City - Mexican volcano Popocatepetl on Saturday threw a large cloud of gas and ash into the air about 80 kilometres east of the capital, Mexico City. The cloud reached a

height of up to two kilometres over the 5,400- metre mountain in the large eruption at 1220 GMT, the national disaster prevention centre said Saturday. Five other minor eruptions had occurred in a 24 hour period, most of which consisted only of steam, the centre said.

Ash rained down on some towns near the volcano, including Atlautla, Tepetlixpa and Amecameca in the state of Mexico, and Iztacalco in the federal district. An area of 12 kilometres around the mountain was blocked off.

Authorities said the activity was likely caused by a mix of water from recent rains with lava.The volcano, known locally as Popo or Don Goyo, has been active for some time, and steam cloud has become a common sight over its peak. copyright, earthtimes 8. How do geologists predict an earthquake or a volcano eruption?

Most geologists (and seismologists) do not predict earthquakes, as so far they have not recognised any warning signs which occur reliably before earthquakes. After earthquakes, people have recognised events which have been interpreted as warnings, such as sudden changes of water level in wells, electrical currents in the earth, emissions of radioactive gases from rocks, but these do not occur before every earthquake, and sometimes the same events occur without any large earthquake occurring. The appearance of sudden and unusual small tremors in an area which has previously been quiet has occasionally been used successfully as a warning of a larger earthquake, for example in China. However such ‘foreshock’ activity is unusual, and quite often it is possible to get a ‘swarm’ of small earthquakes with no larger earthquake following them. Some people suggest using unusual animal behaviour as a warning, but animals can behave strangely without any earthquake occurring, so this is not a reliable warning. It is important that warnings must be reliable, because if there are many false alarms, people will ignore warnings.

It is possible to predict volcanic eruptions with some confidence. Observations made on the volcano, including increases in earthquake activity, swelling of the ground, and the emission of gases from the volcano, can be used for prediction. All these effects are characteristic of the movement of molten rock (magma) under the volcano before an eruption, and the geologists work to describe the movement as best they can in order to predict when the volcano is likely to erupt. Eruptions vary in character, so that it is often not possible to say whether an eruption will take place in days or hours, and what type of eruption it will be. In the worst kind of eruption, a cloud of superheated ash can sweep down the side at high speed, burning everything in its path. Where sufficient observations are available, a fairly reliable warning can usually be issued, which may be partly based on the previous eruption history of the volcano.

What kinds of building designs can withstand a major earthquake?

Few buildings can withstand a major earthquake successfully if it occurs close by. In an earthquake, seismic waves move the ground, and the buildings on it, violently up and down and side to side. Not many buildings can withstand this unless they have been designed and built very carefully. A basic safeguard is to have a strong band of steel or reinforced concrete round the structure, usually positioned at ceiling level in each floor, to hold the building together. If the building twists or deforms then joints between columns and supports can break, so columns and supports must be braced in some way to stop them moving too much. Diagonal beams and solid walls are often used to provide bracing. This is particularly important if there are few walls in one floor of a building (e.g. to accommodate a large garage), as the building then has poor resistance to sideways shaking. In most countries which suffer large earthquakes, strict building rules are used to make sure that buildings are designed and built to minimise earthquake damage.