The sand and gravel resources of the country around Coggeshall, Essex : description of 1:25,000 resource sheet TL 82

The geological maps of the Institute of Geological Sciences, pre-existing borehole information, and 90 boreholes drilled for the Industrial Minerals Assessment Unit, form the basis of the assessment of sand and gravel resources in the country around Coggeshall, Essex. All deposits in the resource sheet area that might be potentially workable for sand and gravel have been investigated and a simple statistical method has been used to estimate their volume. The accompanying 1:25 000 map is divided into five resource blocks or sub-blocks containing between 4.6 and 35.3 km2 of potentially workable sand and gravel. The geology of the deposits is described and the mineral-bearing areas within each block are distinguished. The mean thicknesses of overburden and mineral and the mean gradings, together with detailed borehole data, are also given. The geological lines and symbols, the positions of all IMAU boreholes (including grading information where available) and most other non-confidential boreholes used in the assessment and the outlines of the resource blocks are shown on the accompanying resource map.