TECTONICS OF THE JUNCTION ZONE BETWEEN THE CENTRAL PAMIRS TROUGH AND NORTH PAMIRS UPLIFT

The Central Pamirs trough, trending E - W, lies between the North Pamir uplift and the Pamir- Hindukush uplift. The North Pamir uplift Was a positive Area during the Mesozoic, while continuous deposition took place in the trough. Within the trough the structures are Alpine. The North Pamir uplift is divisible into three zones. Adjacent to the trough and separated from it by a major northdipping thrust is a zone of highly contorted Ordovician strata. To the north, the central zone, also bounded by thrusts, has gently folded Paleozoic strata in the west, passing eastward into complex structures where the zone is narrowest. The Paleozoics of the northernmost zone lie in broad open folds, thrust southward over the central zone and northward over Permian volcanics and sediments. The northern part of the Central Pamirs trough is an area of broad open folds in Mesozoic and Paleozoic sediments, bounded on the north by a belt of generally north-dipping thrust slices of Paleozoic rocks, paralleling the fold trends. Thrust synclines have been thrust both northward and southward over the intervening anticlines, in some cases with superposition of younger beds over older. The structures described can only be the result' of tangential compression. They do not support the current (Russian) theory that the tectonics Of the area are due to gravitational movement of rock masses from uplifts to troughs. -- P. B. Jones.