Hexacopter UAV and Agisoft used to survey spoil tips at Greenside Lead Mines

View down the valley overlooking Tip 1 and the lower working areas at Greenside Lead Mines

At the end of July we were commissioned by the Lake District National Park Authority to undertake topographic survey of the three large spoil tips at the extensive Greenside lead mining complex near Ullswater in the Lake District. Archaeologically the site is of national importance and is protected as a Scheduled Monument. Future management of the property necessitated the present detailed topographic survey in advance of engineering works to maintain the stability and structural integrity of the large spoil tips. The buildings beneath the spoil tips are currently used as hostel accommodation.

Tip 1 precariously sat above the youth hostel at Greenside Lead Mines

Normally such a detailed survey, requiring close contours for the extensive complex would take an inordinate amount of time to survey using traditional survey techniques such as Total Station or even differential GPS.  Over the last few years we have been developing more rapid and cost-effective survey capability using various unmanned aerial vehicles (UAV) to photograph archaeological sites, which is combined with Agisoft software to create 3D models and contours of sites.

Preparations for surveying Tip 3 at Greenside Lead Mines with the hexacopter UAV

Part of the site was surveyed and excavated in 2003-4 in advance to engineering works on Spoil Tip 2 using traditional survey methods, but whilst that took a week or so to undertake the present UAV survey took a day of flying and setting in survey control to cover the entire mine complex.

Surveying at Greenside Lead Mines with our hexacopter UAV

The site was visualised in Agisoft as a digital terrain model in both solid form and also with the aerial photography draped over the top. The data from this model was used to create detailed contours of the earthworks at various scales which could then be used when drawing up the site.

Isometric view up the valley at Greenside Lead Mines – screen capture of a solid texture model in Agisoft

Isometric view up the valley at Greenside Lead Mines – screen capture of a photo texture model in Agisoft

The complete site was also output as a single flattened scaled composite image which was then annotated in the field to add in the finer detail of archaeological structures and provide hatchures to the topographic survey.

Agisoft xy topographic plot of Greenside Lead Mines

The finalised site drawings, contours and survey detail were then compiled into a single CAD drawing for the entire complex and figures created showing both the entire complex and detailed ones of specific features in the complex.

Finished topographic survey of Greenside Lead Mines

Detail of the topographic survey between Tips 1 and 2 at Green side Lead Mines – no photo

Detail of the topographic survey between Tips 1 and 2 at Greenside Lead Mines

Update! – Standingstone Rigg, Northumberland

The drawings depicting the prehistoric stone row and pit alignment that we surveyed at the beginning of the month have now been completed! Profuse thanks must again go to all of the Altogether Archaeology volunteers who gave up their weekend to come out and be part of the survey.

Stone Row at Standingstone Rigg – Topographic Survey

Stone Row at Standingstone Rigg – Aerial Photography

Volunteer Survey at Standingstone Rigg, Northumberland

A training weekend was undertaken on the first weekend in September supervised by myself and Gemma Stewart, the Northumberland National Park Community Archaeologist, to survey a stone row alignment located on the open moorland at Standingstone Rigg, near Simonburn, Northumberland.

Training volunteers to use a theodolite

The project was funded through Northumberland National Park to enable volunteers to undertake practical archaeological projects within the National Park. The aim of the project was to provide appropriate professional supervision and training in order to build the capacity of local groups to actively research little studied or poorly understood elements of the archaeology of the National Park.

The survey falls under the wider umbrella of the Heritage Lottery Funded Altogether Archaeology Project, a multi-period community archaeology project  being undertaken to record archaeological sites in the North Pennines AONB and beyond.

Theodolite recording in progress

The field survey aimed to build upon preliminary survey work carried out in 2012 by Phil and Anne Bowyer, and train volunteers in various survey techniques to create a series of detailed plans of key features associated with the stone row.

Phil and Ann Bowyer 2012 sketch plan of the stone row

The stone row was surveyed using a combination of a theodolite and disto technology to create a manual measured plan of the stones and a differential GPS to record surrounding structures and archaeological features. All upstanding and recumbent stones from the row were measured, described and photographed.

Northern end of the stone row, looking north

Preliminary results of the survey revealed a slightly sinuous NNE/SSW double alignment of both upstanding and recumbent stones that ran upslope over the crest of a ridgeline and down the other side, adjacent to one, or possibly two funerary cairns on the crest of the ridge. The stones have packing stones surrounding them and in the centre of the alignment it is often just the packing stones that survive as the standing stones have been removed for building a nearby sheepfold. The size of the stones does seem to follow the broad pattern of larger examples nearer the crest of the ridge in the north end of the alignment, and it is clear that the sandstone bedrock has been hewn and cleaved up along natural bedding planes often immediately adjacent to where the stones now stand.

Northern end of the stone row, looking south

The southern end of the stone row continues as an alignment of ten pits surviving as part-filled sunken features before it probably disappears into a boggy area to the south. The double stone row is a prehistoric monument  usually dating from the later Neolithic or Bronze Age, and this example is a very rare, if not unique surviving example from Northumberland. In the British Isles sinuous double stone rows which meander across open moorland countryside are more typically associated with the Dartmoor area.

Southern end of the stone row, looking south

These types of monuments are often found in association with other features such as funerary cairns, which is also possibly the case at our example, but so far I have not been able to identify any other stone rows associated with an extant pit alignment.

Pit alignment on the southern end of the stone row

Hexacopter survey at Standingstone Rigg

When the bad weather abated the week after the survey weekend, my manager Jamie Quartermaine returned to site with Gemma and Phil to survey it using his Hexacopter. This is a small remote-controlled helicopter that can be used (in light winds) to take aerial photography of archaeological sites.  The data was processed in Agisoft software to create both a composite photograph of the stone row and a 3D model of the site.

Hopefully when the final results of the project are published the weekend training exercise will have added significantly to our knowledge of the prehistory of Northumberland National Park, and it will have given local volunteers practical skills for recording further monuments in this landscape in the hinterland north of Hadrian’s Wall.

Particular thanks are due to Gemma Stewart for making the project possible, Phil and Anne Bowyer who have been doing so much background work to understand the archaeology of the surrounding landscape (forthcoming Ravensheugh Crags blog post), and the volunteers from Altogether Archaeology and members of Tynedale Archaeology Group who braved the inclement weather. Thanks are also due to the tenant farmer at Great Lonbrough farm and the Nunwick Estates. A special mention should also be given to Stan Beckensall who braved the rain on the Sunday to help survey the stones.

Agisoft plot of the aerial photography at the stone row