The sand and gravel resources of the country around Diss, Norfolk : description of 1:25,000 sheet TM 17 and part of TM 18

The geological maps of the Institute of Geological Sciences, pre-existing borehole information and 120 boreholes drilled for the Industrial Minerals Assessment Unit form the basis of the assessment of the sand and gravel resources of the country around Diss, Norfolk. All the deposits in the district that might be potentially workable for sand and gravel have been investigated and a simple statistical method has been used to estimate the volume. The reliability of the volume estimates is given at the symmetrical 95 per cent probability level. The 1:25 000 map is divided into six resource blocks, containing from 7.8 to 34.1 km2 of sand and gravel; the deposits in each block are described. For all six blocks a statistical assessment of the sand and gravel resources is made and the mineral-bearing areas, the mean thicknesses of overburden and mineral and the mean gradings are given. The positions of boreholes and data recorded from them, the geology and the outlines of the blocks are shown on the accompanying resources sheet.