Earthwatcher's photos with the keyword: unguessed

Originally uploaded for the GWUK group. This is on Mynydd y Gwair - an extensive moorland commons between Swansea and Ammanford in the South Wales coalfield. The camera location is on Mynydd Garn Fach and is looking north-westerly. The photo shows a Foraky rotary drilling rig on a borehole known as 'Ceunant Borehole' (named after nearby Ceunant Farm just out of view to the left). This was drilled to prove the Red Vein coal seam in October-November 1982 as part of a series of boreholes to prove additional coal reserves for Betws Mine, about 5 km to the north, near Ammanford.

The folds are superficial valley-bulge structures in the weak Namurian shales and do not extend more than a few metres into the subsurface. They have formed as a result of the differential loading of the valley sides and valley bottom - the weak valley floor sort of squidges up. This originates mainly from melting of permafrost conditions at the end of the last glacial period around 11,500 years ago. Continuing movement of the valley sides causes the landslides which periodically disrupt the A57 Snake Pass road nearby on the north flank of the valley.

Originally posted for the Guesswehere UK group. It's the No.4 ventilation shaft for the Totley Tunnel, on the Sheffield-Manchester railway. At 3 1/2 miles long, it's the 2nd-longest railway tunnel in the UK (after the Severn Tunnel). It was driven from both ends - the two headings thirling through in 1892. The line opened for freight in 1893 and for passenger traffic shortly after. There are 5 shafts along the length of the tunnel. Nos 1 - 4 are all fairly close to each other at the Totley end; No.5 Shaft is high up on the moors nearer the Grindleford end.