This layer of the map based index (GeoIndex) shows the location of available Mineral Assessment Reports, the information for the index has been taken from the BGS UK Sand and Gravel Database. Each report studied the sand and gravel resources of an area of between one hundred and two hundred square kilometres. This layer shows individual polygons of the geographical areas covered by each report. Selecting the individual polygons via the map based index (GeoIndex) application gives details of the corresponding report title, number, author(s), subtitle and the date report was first published. The Department of the Environment commissioned this Report series from the British Geological Survey.