Contemporary in situ stress determinations at three sites in Scotland and northern England

During 1987, in situ stress measurements using two overcoring techniques (doorstopper and triaxial strain cell) were made in England and Scotland as part of the former SFB 108 Project ‘Stress and Stress Release in the Lithosphere’ at Karlsruhe University. The results for three of the test sites—Spittal in Caithness, Gartur in the Midland Valley of Scotland and at Burton in Cumbria—are reported. Complementary studies on cores from Gartur using portable ASR equipment are included. The maximum horizontal stress orientations agree closely with those seen in the general contemporary stress field in NW Europe. These results confirm that, in favourable circumstances, these shallow methods offer effective approaches to the acquisition of reliable contemporary stress information, whether derived from boreholes or rock cores.