. Former Soviet Union conducted 132 nuclear test between Sept 21, 55 and Oct 24, 90

. 87 athmosphere (1 surface, 3 water surface, 83 air bursts)

. 3 underwater between 55-62

. 42 underground between 64-90

. The underground nuclear test site, loca´ted along the Matochkin Shar strai is the only former Soviet nuclear test site that is presently declared under the 1963 Threshold Test Ban Treaty (TTBT)

. An underground site on the southern part of the islands was deactivated 1975

. Underground tests average one or two per year between 1964 an 1990

. Matochkin Shar test site: 36 test during 64-90

. Matoshkin Shar site is composed of bedded, fractured and faulted sedimentary rocks which dip to the northwest, but are near vertical in Mt. Lasareff, along the strait, where some testing has occured

. deformation of therocks in the test area is due primarly to thrust faulting, though folding occurs

. The tests have occured in low-porosity rocks of middle Paleozoic age, mostly shale, siltstone, sandstone, quartzite, and conglomeate with lesser amounts of limestone and dolomite

. Descriptions of sericite and chlorite schists and quartzites at Matochkin Shar suggests that the rocks are metamorphosed to he Greenschists fascies.

. The largest granitic intrusion on Novaya Zemlya is located on the northern side of the straits, about 20 km to the westt of the current testing region

. No underground test are known to have occured in the granite

. NZ is located in the zone of continuous permafrost

. Up to 600 m thick in the higher mountains

. Uncertain if the tests have occured within or below the permafrost