The sand and gravel resources of the country south of Wrexham, Clwyd : description of 1:25,000 resource sheet SJ 34 and parts of SJ 24

The geological maps of the Institute of Geological
Sciences, pre-existing borehole information, and 70 boreholes
drilled for the Industrial Minerals Assessment Unit
form the basis of the assessment of the sand and gravel
resources of the area south of Wrexham, Clwyd.
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 mineral-bearing ground is divided into four
resource blocks, containing between 9.4 and 18.4 km2 of
sand and gravel. For each block the geology of the
deposits is described, and the mineral-bearing area, the
mean thickness of overburden and mineral and the mean
grading of the mineral are stated. Detailed borehole data
are also given. The geology, the position of the boreholes
and the outlines of the resource blocks are shown
on the accompanying resource map.