Brockholes
A Walk around Brockholes to look at the Rocks, Fossils and Landscapes
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Image produced from the Ordnance Survey Get-
Rough Rock sandstone in quarry next to Tor Rocks, Brockholes.
The rocks of the Brockholes area are Upper Carboniferous (Langsettian) in age, so they are about 310 million years old.
These rocks were laid down in deltas on the edge of a large continent, with mountains to the north and south. Sands and muds were deposited by rivers in shallow water. Because the continent was close to the equator, the climate was warm and wet so that tropical rain forest flourished. Dead plant material became trapped in stagnant swamps between river channels. Over geological time it was buried by muds and sands as the rivers in the delta changed position and built up more deposits. The water, oxygen and hydrogen were driven out of the plant remains, leaving only the carbon in coal seams.
After the sediments were formed close to sea-
These rocks, particularly the mudstones, contain fossils, of which the most important are goniatites. There are several layers of mudstone which contain goniatites, as well as other fossils, such as shells and microfossils. One fossiliferous layer is exposed in a stream gully in Round Wood and goniatites and bivalves can be found there.
Most of Brockholes is built on sandstone called the Rough Rock, which has been quarried extensively. It can be worked into an excellent building stone so has been widely quarried throughout West Yorkshire. There are several coal seams which have been exploited in the Brockholes area, probably for several hundred years until the 1940s.
WEST
Cross section to show the geology of the Brockholes area.
EAST
Mudstones are white
Sandstones are yellow
The landscape of West Yorkshire is largely controlled by underlying geology. The Rough Rock is a thick, resistant bed of sandstone which forms many gently sloping plateaux in the Huddersfield and Halifax areas, including the slope on which Honley stands. The mudstones are less resistant and are weathered and eroded more easily, so are exposed in the cloughs and valleys.
This pattern of erosion on the sandstones and mudstones is common and gives West Yorkshire its characteristic landscapes of flatter moorlands formed by sandstones and steeper slopes formed by mudstones.
Goniatite
Brockholes
Rough Rock
Greenmoor Rock
Coal seams
Honley
Thurstonland
Grid Reference
SE 151 110