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igneous and sedimentary rock sequence deposited in an oceanic environment
(Geological map of Tadzhik SSR 1983, Ruzhentsev and Shvol’mann 1982). This cover
encloses volcanic rocks (Burtman & Molnar 1993), which are unconformably overlain by
flysch-greywacke sequences of Middle to Upper Carboniferous and Permian age. All
strata were deformed in the latest Palaeozoic, during the closure of the Palaeotethys.
The southern subzone consists predominantly of Late Palaeozoic flysch and molasse
sediments and a narrow band of Middle to Upper Triassic basaltic andesites belonging
to a calc-alkaline series (Burtman & Molnar 1993). These volcanic rocks unconformably
overlie the Palaeozoic rocks. In the Lake Karakul area large batholiths of Triassic age
are widespread. This area represents a large depression dominantly filled with
Quaternary lacustrine and glacial deposits (Strecker et al. 1995b). In the eastern part of
the Northern Pamirs, the active Markansu fault in the north and the Aksu-Rangkul fault
in the south document dextral strike-slip; intervening is the rift structure of the Karakul
area. In the southern part of the Northern Pamirs thrust faults are south vergent. This
southern margin of the Northern Pamirs documents the Late Palaeozoic accretion of the
Central Pamirs (Burtman & Molnar 1993). Neither the exact closing time of the suture
nor an intervening oceanic basin are well constrained. Based on oceanic rock
assemblages, the Late Palaeozoic suture can be traced from the southern margin of the
Northern Pamirs, where it is called Tanymas suture, into the northern Hindu Kush in
Afghanistan, and into the Kunlun in Tibet (Burtman & Molnar 1993).
Central Pamirs, Rushan Pshart Zone, and South Pamirs
The Late Palaeozoic and Mesozoic history of the Central Pamirs, Rushan Pshart
zone (RPZ), and of the South Pamirs (Fig. 1.1 and 3.1) has been much debated. In
tectonic and palaeogeographic reconstructions, Karapetov et al. (1975), Shvol´man
(1978), Pashkov & Shvol´man (1979) and Shvol´man & Pashkov (1986) interpret the RPZ
as a major tectonic suture extending into Afghanistan and Tibet, and marking the
consumption of a Permo-Triassic ocean that closed during the Jurassic. In some
palaeotectonic reconstructions, the oceanic basin is thought to have been more than
2000 km wide in the Triassic (Sengör 1990).
Burtman & Molnar (1993) pointed out that the Khas Rud ophiolite in Afghanistan is
likely an equivalent of the RPZ. Late Palaeozoic to Mesozoic sedimentary sequences of
the Farah Rud basin in Afghanistan were apparently deposited on a passive
continental margin and can be correlated to sequences near the southern edge of the
Central Pamirs. The eastward continuation of the Farah Rud and RPZ to Tibet is more
problematic: two ophiolite belts are commonly interpreted as Mesozoic sutures in
Central Tibet. One lies south of the Kunlun mountains (e.g. Pearce & Deng 1988, Sengör
1984) extending to north-eastern Tibet. The other one is the Banggong suture (e.g.
Matte et al. 1992) in western Tibet. Burtman & Molnar (1993) aligned the west Kunlun
suture with the RPZ and the Banggong suture with the Shyok suture. The Shyok and
Indus-Tsangpo ophiolite belts mark the suture between India and Eurasia and
intervening island arcs; in latest Mesozoic the Karakoram, Kohistan and Ladakh were
incorporated and in early Cenozoic time India was involved (e.g., Petterson & Windley
1985, Coward et al. 1987).
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