Thynghowe Viking Assembly Site Sherwood Forest Nottinghamshire England Dig site early April 2016. Ground to left cleared of small birch trees and rhododendron. Beech trees to right situated in the monument feature but clear of trench lines.
Methodology and Archaeological Discovery
Rescue archaeology occurs on sites about to be destroyed but, on occasion, may include in situ preservation of any finds or protective measures taken to preserve an unexcavated site. In closed canopy woodland survey methods in 2005 were limited.
Plane Table Survey Technique: Alidade and Tape Extendable Measures – Optical Squares
GPS and the difficulties of working in closed canopy woodland - Traditional techniques still have advantages in the detailed analytical survey of archaeological earthworks at large scale (usually 1:1000 or 1:500), where understanding and interpretation are as important as accurate recording. No one should confuse the ability to use electronic instruments with the ability to see and understand archaeological remains; the second is not necessarily a corollary of the first.
Early work in the Forest: Recording the profile of an 18th century 'Saw Pit' with a community group Field surveys undertaken using a combination of electronic and traditional techniques offer: • a descriptive and analytical account of the site • an accurate and analytical plan • relative heights and profiles where necessary • an accurate location • a platform on which to base further interpretation • a permanent record of the site at a given time
Topographical Survey – Total Station, Prisms and clear line of site GPS Modern sites use either GPS or commonly the Total Station for site survey, grid location, coordinating artifacts or samples. The total station is an electronic theodolite (transit) integrated with an electronic distance meter (EDM) to read slope distances from the instrument to a particular point.
Topographical Survey: Community Involvement on site Open Days
Topographical Survey Part of Circle and Enclosure revealed Conventional hachured survey has been found the best way to portray earthworks and their interrelationships. This is because arrays of hachures can: • indicate the all-important relative chronology of features • distinguish between natural and artificial slopes; • give a consistent portrayal of earthworks as they turn across or along natural slopes.
Magnetometry – on what is possibly a Bronze Age Mound (2300 BC- 800 BC) and Viking Law Rock
Magnetometry is the technique of measuring and mapping patterns of magnetism in the soil. Ancient activity, particularly burning, leaves magnetic traces that show up even today when detected with the right equipment. Buried features such as ditches or pits, when they are filled with burnt or partly burnt materials, can show up clearly and give us an image of subsurface archaeology.
The Law Rock: Laying out the grid for the Magnetometry The survey area is laid out in a regular grid, with each metre point marked on string lines. To avoid contaminating the readings, surveyors must be free of magnetic materials, so watches, rings and credit cards must be left away from the survey area. Their clothing must not contain metallic zips, buttons, studs or other such fastenings.
Overlay of Magnetometry results on to the hatchured plan Readings are usually taken every metre or half-metre and then down-loaded from the magnetometer onto a computer and plotted using a special graphics program. The results are usually plotted in squares representing the survey grid, with magnetic variations being represented by darker or lighter colours. When all the grid squares are joined together, they give a full area picture of patterns of magnetism, which can then be interpreted archaeologically.
Topographical Survey Part of Court Circle and Enclosure
THYNGHOWE
THYNGHOWE
The flyover polygon for LiDAR capture
THYNGHOWE
King's Wood
Undertaken with three flyovers at half meter detail plotted on a wide polygon to capture as much of the National Nature Reserve and Birklands as possible within budget for bench mark at 2012.
The task of data analysis: converting a raw file to fine landscape information
By using experts in the field of LiDAR we were able to access different experiences of interpretation. LiDAR allows for changes in light direction (sunrise and sunset) which increases and diminishes shadow direction which can reveal otherwise unseen features.
The Forest landscape with the trees removed. This left clear images of the most distinct earth movements on the Forest floor and gave height information. Red high blue low.
By manipulation of the data we could measure height and depth of earthworks. This a picture of medieval earthworks, a deer leap, in King's Wood the red areas are the highest
An image of a medieval trackway and a 300 year old Estate ride. This time using LiDAR with the trees still in place
LiDAR data triangulated against Ministry of Defence Arial Photography and Ground Truthing. The same trackway and Ride in 1956
Creating a record of archaeology in the forest to inform the Forestry Commission Management Plan and direct contractors during extraction work.
Ground truthing – using ranging poles – extendable measures and theodolite – creating grids – and back markers to record features.
Ground truthing using ranging poles, tape measures, and a Dumpy Level to plot a Viking Hollow Way.
Ground truthing using extendable measures to create line of sight markers for use on community survey days .
Building a wider understanding of archaeology in the bigger landscape
LiDAR overhead view of the topography of the wider Thynghowe site and landscape
THYNGHOWE
LiDAR close up view of the Thynghowe Law Rock, Sand Circle and enclosure earthworks.
LAW ROCK
MEDIEVAL PLOUGH LINES
COURT CIRCLE
TEST TRENCH 2013
ENCLOSURE BOUNDARY DITCH
2013 Test Pit on the Sand Circle
2013 test pit to confirm the extent, the composition and the age of the circle monument. Of considerable size – 60 meters across – enclosed by bank and ditch
2013 Test Trench: Bank and Ditch Profile
The feature was judged to be of great antiquity – but no conclusive evidence of the time of its construction.
Focus of 2016 Dig: Two trenches where the circle bank and ditches were indistinct from the LiDAR data
TRENCH TWO
TEST PIT
TRENCH ONE
Trench 2: Where the enclosure boundary, the Parish of Warsop boundary, the Township of Budby boundary and the court circle meet.
Trench 2: Did one earthwork cut into the other?
WARSOP BANK
BUDBY DITCH
CIRCLE DITCH
Test pit: Fire cracked pebbles – or pot boilers. Fire Cracked Pebbles which were used as prehistoric pot boilers have frequently been associated with the features of Iron Age settlement but not exclusively – Vikings used them as well.
How to date events in the past: Thermoluminescence (TL) or thermally stimulated luminescence (TSL) measures energy emitted after an object has been exposed to temperatures between 400 and 500°C
Up close and personal in Trench 1 – it's all about sifting – sorting sand for possible dating evidence
Trench 1: At the top of Thynghowe where the Court Circle meets the boundary between Budby and Edwinstowe
Up close and personal in Test Pit 3 – its all about the stratigraphy – were the pot boilers all from the same event?
Finds: Mesolithic soft hammered flint Trench 1 The Mesolithic (or "middle stone") period is traditionally that time period in the Old World between the last glaciation at the end of the Paleolithic (~12,000 years ago) and the beginning of the Neolithic (~7000 years ago), when farming communities began to be established.
A hard hammered Neolithic flint Trench 1 The Neolithic period ('New Stone Age') in Britain dates from about 4000 - 2300 BC, and is traditionally defined by the change of economy from one based on hunting and gathering to one based on the the growing of crops (barley, wheat, and pulses) and breeding of animals (sheep, goats, cattle and pigs).
Possible Iron Age Quern Stone fragment from Pot Boiler Test Pit in Britain, because they had few imports from mainland Europe, the Iron Age is divided into Early (800- 400 BC), Middle (400-120 BC) and Late (120 BC-AD 43). The successful invasion of Britain by the Romans under the Emperor Claudius in AD 43 is taken as the official end of the Iron Age in Britain.
Monitoring closely the changes in sand colour to define the mounds and ditches – not easy in bright sunshine and shade
A cleaned profile in Trench 1 revealing a constant design – the same as found in the 2013 Test Trench and giving a complete circle monument
The feature would have been a clearly defined golden sand circle with a centre at certain times of the year covered in purple heather
TOP OF CIRCLE MOUND
Environmental soil sampling Trench 1
Searching for ‘ecofacts’ such as plant and animal remains, is a useful means of reconstructing how the ecology and environment of the surrounding land may have once been, and how it has changed. SAMPLE TAKEN FROM BOTTOM OF CIRCLE DITCH
Thank you to the Nova Scotia Archaeology Society for inviting us to present on our work in Sherwood Forest. Thank you to The Friends of Thynghowe for all their continued hard work. Thank you to Mercian Archaeological Services CIC Thank you to the Forestry Commission England Thank you to the Heritage Lottery Fund
THE LINK TO THE SLIDES USED IN THE PRESENTATION CAN BE FOUND ON OUR FACEBOOK PAGE AT
facebook.com/thynghowe And finally, thank you for coming.