Wednesday, 16 October 2013

TELLUS A STORY: Filming for the TELLUS SW project... by Clive Mitchell

Me [Clive Mitchell] at Bigbury
Many of you have been following the work being carried out for the TELLUS South West project. (previous post with even more photos!!) In a nutshell, this project includes airborne geophysical and LiDAR surveys, geochemical sampling of stream sediments and a soil and habitat survey. Probably the most visible aspect is the on-going high-resolution airborne geophysical survey which involves low level flying over Cornwall, Devon and parts of Somerset. It was decided that a video would be made to highlight the benefits of the data forthcoming from the project which would be premiered as part of the TELLUS SW conference at the Eden Project on the 31st October (no pressure then!).

Ed and Andy at Bigbury
The film crew included myself (Clive Mitchell, part-Geologist, part-Press Officer), Andy Howard (BGS Director of Science for Geology and Regional Geophysics) and Ed Collard (film maker from Widecast). Armed with a schedule of interviews with people across Cornwall and Devon for the second week of October, put together with the help of Emma Ward at BGS and Cally Oldershaw at Camborne School of Mines (CSM), we set out…

Monday 7th October
On a particularly grey looking day (not unusual for the East Midlands it seems), we set out for the southwest passing through north Somerset on the way (my home turf, Hi Mum!) and by mid-afternoon we had arrived at our filming base in Plymouth. So as not to waste time, and because we were keen to start filming, we headed out to the coast.
Filming location 1: Sedgewell Cove, Bigbury-on-Sea, Devon (Devonian siltstones).
Close to Burgh Island, a tidal island where Agatha Christie once holed up to write her murder mysteries. Ed and Andy made a start on the filming for the TELLUS SW project. It's overcast and drizzling but it's actually quite mild for the time of year. Surf is up with a handful of surfers braving the waves. It’s great to be by the seaside, although all I can think of during the filming is fish and chips!

(I eventually get my fish and chips at The Dolphin, Newton Ferrers).

Richard Scrivener holding ore samples
Tuesday 8th October
Filming Location 2: Hemerdon, Devon (Mineralised granite dykes intruded into Devonian slates)
We met up with ex-BGS geologist Richard Scrivener at the Miners Arms pub in the tiny Devon hamlet of Hemerdon which is just to the southwest of Dartmoor. Richard took us to a vantage point on Crownhill Down looking towards Drakeland Corner and the old mineral workings at Hemerdon Ball. This is the site of the Hemerdon tungsten deposit, one of the largest in the world, which is due to start production in 2015. Next we visited Hemerdon Ball which was previously worked for tungsten in the Second World War. Evidence of the mineralisation (90% tungsten in the form of the mineral wolframite and 10% tin in the form of the mineral cassiterite) was found in veins on the edges of the pit.

Filming Location 3: Tremough Campus, Camborne School of Mines (CSM), Penryn, Cornwall
From Hemerdon we headed west into Cornwall and to the Penryn campus (just north of Falmouth) of the Camborne School of Mines (CSM). Our first interview was with Professor Mark Smethurst (Honorary Professor of Applied Geophysics visiting from the Geological Survey of Norway) who is a Radon expert. In his opinion, the data from the radiometric survey carried out by TELLUS SW will be “worth its weight in gold” as it will significantly improve the understanding of the concentration of radon in dwellings in the southwest. In particular it should highlight local extreme exposure sites that may require special attention.

Ed, Cally and Niell with Quadcopter
The head of the department, Professor Frances Wall, was then filmed walking through the corridors of CSM popping into the laboratories, offices and ending up in the mineral gallery, generally taking people by surprise!

Next we had a demonstration of an Unmanned Aerial Vehicle (UAV) by Neill Wood. The QuadCopter was equipped with a GoPro camera. We were treated to a 7 minute aerial display (the length of time Neill dares to fly the QuadCopter before its battery runs out and crash lands!) and, much to his delight, it made a perfect landing!

On the way back to way back to Plymouth we stopped off in Truro so that Ed could film Truro Cathedral. The cathedral is 80m tall, which is the height the TELLUS SW survey plane flies over open countryside (200m over populated areas).

Ed and Tony Bennet down the mine
Wednesday 9th October
Filming Location 4: Rosevale Mine, Zennor, Cornwall (tin mineralised granite)
At 8am we set off on the 2 hour drive across to the west of Cornwall. We met Tony Bennett from EGS Energy in the car park at Zennor. Tony took us up to Rosevale Mine which, along with 4 friends, is essentially run as a ‘hobby’ mine! Rosevale Mine is only accessible on request and is not generally open to the public. This is a former tin mine which originally opened in the 18th century and was worked until the First World War. There is very easy access through a drift adit into one of the mining levels. Luckily it was relatively free of water due to the recent dry weather and to the fact that it is a free draining operation not requiring an engine house to pump out water. There are not many places in Cornwall where you can truly experience what it was like to be a tin miner. Tony is the operations manager at EGS Energy which is looking to develop geothermal energy in the region. EGS is currently working at the Eden Project where it plans to drill a deep borehole into the underlying granite. Water pumped down will heat up to 180oC and the superheated steam will return through a second borehole to the surface where it will be used to generate electricity ad as a source of heating.

Next we drove across to St. Agnes Head where we met Mark Owen from Wardell Armstrong for lunch at the Driftwood Spars, Trevaunance Cove. Mark is a mining geologist with many years of experience in the industry including time as Chief Geologist at South Crofty (the last operating tin mine in the UK which closed in 1998). After lunch we walked out onto the beach from where the mining history of this part of Cornwall is all too visible with the relic of a tin mine engine house overlooking the village, the rubble of the former harbour from where tin was exported and the small tin mine adits that pockmark the cliffs.

Ed and Mark on the beach
The last stop of the day was at Cligga Head where the remains of a tin processing plant can be found, with evidence of ‘Buddles’ (used to concentrate the cassiterite). We got some great shots of the coast east towards Perranporth beach and west back towards St. Agnes Head. Afterwards we headed back to the BGS filming base in Plymouth where we reconvened to review the day’s footage in the hotel bar.

Thursday 10th October
Last day in the southwest! We checked out of the hotel and headed back over the Tamar into Cornwall for the last time this trip.
Filming location 5: Minions Heritage Centre, Bodmin Moor, Cornwall (copper and tin mineralised granite)
We met Deborah Boden from the Cornish Mining World Heritage Site at Minions Heritage Centre on Bodmin Moor. In a change to the weather of the last 3 days, it was gloriously sunny but also a lot colder! The heritage centre is based in Housemans Engine House, which was built in 1881 as part of South Phoenix Mine. It was purchased and restored by Caradon District Council on behalf of the Minions area heritage project with grant aid from the Rural Development Commission in 1991. As we filmed ponies were galloping around and generally looking photogenic. Beryl Martin, key holder for the heritage centre and Minions Parish councillor, popped out to have a chat with us. The centre has a series of displays that focus on the mining history, geology and past life of the area. It was in 1836 that a rich lode of copper ore was discovered just south of the present day village of Minions. This precipitated a ‘Copper Rush’ with miners coming from all over the southwest for work creating a mining boom. The railway soon followed, which explains why Minions was actually known as ‘Cheesewring railway’ at this time. Tin and arsenic were subsequently mined.
Housemans Engine House
However in time the mines were exhausted, competition from overseas increased causing prices to collapse and by 1914 all of the mines had closed.

It’s a wrap! The last filming took place at vantage points looking towards Cheesewring Tor and granite quarry. We set of back to the East Midlands and I arrived home about 8.30pm. Ed still has some filming to do with the survey pane at some point (this took place the following week) and the video will be released at the end of October 2013.

 Clive Mitchell

1 comment:

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