The sand and gravel resources of the country north and west of Billingham, Cleveland : description of 1:25,000 sheets NZ 42 and part of NZ 52

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 country north and west of
Billingham, Cleveland.
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 two
resource blocks, containing 12.5 and 10.6 km2 of
potentially workable 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 gradings 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 map.