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Project launch
Geophysics surveys
Geological survey Downley Common
Archaeology of Downley Common - photos
Downley School excavation
Bricks and brick-making
Events next in the programme
Art and archaeology on Downley Common
Poetry at Downley School
Maps and archaeology
The 'Big Dig'
Art workshop on Downley Common
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Geological survey Downley Common
Location: Buckinghamshire
There were several aspects to the geological survey. Firstly, the soil and vegetation types were recorded and this changes considerably over the site. There are distinctive clay areas, chalky soils and also very light sandy soils. The vegetation changes from dense woodland, mostly on the clay to grassland with heather and gorse on the sands, to a mixture of trees and scrub on the thin chalky soils.
Secondly, auger traverses were undertaken to determine what the sequence of soils and sediments were in several locations and to obtain some good samples for later analysis.
Thirdly, in one area it was impossible to auger and a small exploratory trench was dug to determine the strata.
The results were that there are two types of clay present: clay-with-flints for the bulk of the land area, with Reading Beds clay preserved in hollows - many of which have been dug out for brick-making use.
The sands were a surprise - the team had expected Reading Beds sands, but were surprised to see a very fine deposit (silt not sand) which is called loess and is wind-blown dust from the last ice age!
The chalk is close to the surface where these other deposits have not been deposited or were since eroded away.
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