The sand and gravel resources of the Loddon Valley area : description of 1:25,000 sheets SU 75, 76 and parts of SU 64, 65, 66 and 74

The geological maps of the Institute of Geological Sciences, pre-existing borehole information, and 131 boreholes drilled for the Industrial Minerals Assessment Unit, form the basis of the assessment of sand and gravel resources in the area of the Loddon Valley in the counties of Berkshire and Hampshire. All deposits in the area which might be potentially workable for sand and gravel have been investigated and a simple statistical method has been used to estimate their volume. The reliability of these estimates is given at the 95 per cent confidence level. The 1:25 000 map is divided into seven resource blocks containing from 5.0 km2 to 13.2 km2 of sand and gravel. For each block, the geology of the deposits is described and the mineral-bearing areas, the mean thickness of overburden and mineral and the mean grading are given, together with detailed borehole data. The position of the boreholes, the geological lines and the outlines of the blocks are shown on the accompanying resource map which covers sheets SU 75, 76 and parts of SU 64, 65, 66 and 74.