'Institute of Geological Sciences of the National Academy of Sciences of Ukraine'
Abstract
Economic deposits of chromite were discovered in Unst, Shetland
Islands in the early part of the nineteenth century and extraction
continuedi ntermittentlyu ntil exhaustiono f the known near-surface
deposits in 1945. Since it is likely that further comparable deposits
exist at shallow depth, detailed geophysical smeys employing
2
magnetic and electrical methods were carried out over ? km of the area
of known mineralisationt o test the feasabilityo f detectinga nd
delineatingt hem. Seven of 16 small positive gravity arumaJ.ie&se
tested by shallow boreholes but only two were attributed to chromite
concentrations.T he gravity anomaliesa t the other borehole sites
remain unexplained; they may be due to unidentified variations in bedrock
density at depth; they may be
of weathering and the thickness of
in overburden thickness
