Friday, 16 March 2018

Lidar Landscapes

I am writing this blog post at this year’s Archaeology Day (10 March 2018), organised by the Durham County Council Archaeology Section. One of the displays I put together for the event is about the project on which we have been collaborating with the Archaeology Section. 

Durham at War Lidar Landscapes began in early 2017 with a workshop introducing interested volunteers to Lidar and its use in archaeology. Lidar (originally a portmanteau of ‘light’ and ‘radar’) is a relatively new information source being used by archaeologists to discover, interpret and record archaeological sites. The data for this project, provided free of charge by the Environment Agency, was gathered using sensors mounted on an aircraft. This data can be processed to make a computerised 3D model of the ground and all the features on it, in effect producing what is termed a ‘Lidar map’. For this project the 3D data collected has been processed to produce 2D ‘hillshaded’ images; this technique emphasises features on the ground, including surviving earthworks of archaeological sites and allows the data to be used as image files which can be viewed on home computers.
Digital surface model and digital terrain model of Dene Mouth , Horden
Digital surface model and digital terrain model of Dene Mouth , Horden

The workshop was given by Paul Frodsham of Oracle Heritage Services, who introduced us (I was new to it too) to what Lidar is, and how to analyse it (you can read more about the methodology in the report, see below). Ten separate survey areas were chosen by the Project Team, eight in County Durham and two in Tyne and Wear. These vary in size from a single km square to 5 km squares. Each was chosen because of the known or suspected presence of features relating to the First World War, such as training camps, prisoner of war camps or training trenches. The ten areas included: 
Whitburn and South Shields 
Cocken Hall, near Durham City 

After the workshop, volunteers were sent data for a km square at a time, this comprised four jpegs sent by email: DTM, DSM, OS map, and aerial photograph. They analysed the data at home at their own pace, and returned their findings by email. Once all the km squares had been looked at, Paul went through the data and a produced a report. You can download this in pdf format from the Durham at War website: 

In February this year, we began a second phase project. For this, we wanted to look at a larger, and continuous, area, as opposed to sites dotted around the county. This will enable us to complete a landscape survey as well as looking for things of archaeological interest.
Area is orange shows Lidar being looked at for 2018 project
Area is orange shows Lidar being looked at for 2018 project
Like before, as this is a First World War project, the area has been selected with this mind. We know there was military activity from this time in the Seaham and Dawdon area. This activity included the submarine bombardment, three Voluntary Aid Detachment hospitals, and 4th Battalion Durham Light Infantry on coastal defence. The rest of the selection was then made based on coverage. 

Since the first phase of the project, we have found a website that itself is concerned with providing data for home insurance, but provides processed Lidar coverage for England and Wales. It is not possible to search the map, but clicking on an area provides a grid reference that can be used to help orient yourself:

A report for this project will be produced at the end, and will again be put online. 

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