This is one of several stone quarries around the villages of Read and Simonstone. Stone from here is said to have been used in the building of Whalley Abbey, 1296-1537, and of course for local buildings and drystone walls which have been a feature of upland Britain since the Iron Age. Across the road are the ruins of perhaps a quarryman's cottage or a toll bar. What do you think?
Geology of the area
Millstone Grit is the name given to any of a number of coarse-grained sandstones of Carboniferous age which occur in Northern England. The name derives from its use in earlier times as a source of millstones for use principally in watermills. Geologists refer to the whole suite of rocks that encompass the individual limestone beds and the intervening mudstones as the Millstone Grit Group. The term Millstone Grit Series was formerly used to refer to the rocks now included within the Millstone Grit Group together with the underlying Edale Shale Group. The term gritstone describes any sandstone composed of coarse angular grains, (usually capitalised by British rock climbers) and specifically refers to such sandstones within the Peak District, Pennines and neighbouring areas of Northern England.
The high ground here on Black Hill and across the valley on Pendle Hill is dominated by Namurian (Millstone Grit) sandstones, chiefly Pendle Grit, which is a coarse to medium grained stone that occurs in massive beds up to 4.5m thick.
In the glaciated valley between Black Hill and Pendle hill, around the town of Sabden, there are layers of glacial till fringing the higher land, which were deposited during the the last Ice Age. North of Pendle around Clitheroe, the geology is dominated by limestone, and south of this quarry around the actual villages of Read and Simonstone, there are coal measures.
Quarry Zones
In the quarry, as you face the back wall you will see three distinct zones of rock, with a fourth zone over to your right slightly behind you.
The three zones are tilted at an angle due to folding and faulting during periods of uplift. The separate zones can be identified by the pattern of cracks that appear along the bedding plains.The fourth zone appears not to have been tilted.
To log the cache:-
1 Research and provide approximate dates of the start and finish of the Namurian Period, saying which major era this is a sub-division of.
2 Study the three zones from left to right and give the approximate distance interval between their cracks in each case. A) State the approximate angle of tilt fom horizontal, B) Speculate why the three zones differ, C) Do you think one zone was ever on top of another?
3 From the evidence on the quarry floor, what do you think they were making when the quarry was abandoned?
4 Photos, not giving away answers are welcomed but not obligatory.
Please send answers to CO via geocaching profile page. You do not need to await confirmation before logging. Logs without answers will be deleted after a couple of days.