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1 Introduction
Until the 1990s, geological surveying of the Pamirs focused on Precambrian geology
and ore exploration. At the same time, the neighbouring Himalayas and Tibet (Fig. 1.1)
were studied applying modern mountain building theories. Despite the shortage of
modern data, several scientists were successfully placing the Pamirs’ geologic history
into a plate tectonic framework (e.g. Zonenshain et al. 1990, Burtman & Molnar 1993).
In accordance with the tectonic history of other Central Asian regions, the Pamir crust
amalgamated over several orogenic cycles during the Palaeozoic and Mesozoic.
Although attempts have been made to correlate Palaeozoic and Mesozoic sutures in
the Tien Shan and Pamirs with those in Tibet and Afghanistan, mapping of ophiolites
and related rocks has not sufficiently highlighted the sutures. Likewise is the structural
relationship, number, identity, and evolution of intervening blocks in the Central Asian
region still poorly known. Attempts to correlate Palaeozoic and Mesozoic sutures from
Tibet or Afghanistan across the Pamirs are problematic. This is by virtue of northward
deflection of the Pamirs relative to the neighbouring areas in the east and west.
Another difficulty arises from significant post-collisional shortening during the
Cenozoic India-Asia collision. Although this collision occurred approximately 1000 km
south of the Pamirs, it has dramatically reshaped the Pamirs until recently. Much of the
research in Central Asia of the last two decades focused on Tibet and on the tectonic
activity post-dating the India-Asia collision (e.g. Tapponnier & Molnar 1977; Dewey et
al. 1989, Yin & Harrison 2000 and several others). By contrast, only little is published
about the post-collisional history of the Pamirs (Arrowsmith & Strecker 1999; Burtman
& Molnar 1993; Coutand et al. 2002; Ducea et al. 2003; Frisch et al. 1994a, 1994b;
Hubbard et al. 1997, 1999; Pavlis & Hamburger 1997; Ratschbacher & Schwab 1999;
Ratschbacher et al. 1996, 1997; Schwab et al. 1997, 1999, 2000; Strecker et al. 1994a,
1994b, 1995a, 1995b, 2003). Nevertheless, reconstructions of Cenozoic deformation
resulting from the India-Asia collision are considered preliminary owing to insufficient
knowledge of the pre-collisional geometry of Central Asia. Identification of pre-
Cenozoic sutures can provide crustal markers which aid in unravelling Cenozoic
shortening and displacements. This in turn facilitates understanding and
reconstruction of tectonic events that were affecting the Pamirs.
The aim of this study is to elucidate the Pamirs’ pre- and post-collisional tectonothermal
evolution and to help understanding the development of the Pamir-Tibet
orogenic setting, responsible for constructing one of the Earth’s largest mountain belts.
Data collection was concentrated across E-W striking magmatic belts and along a N-S
traverse from South Tien Shan (STS) through the eastern Pamirs.
The following main questions are addressed:
� What is the age and origin of the E-W striking magmatic belts and what was
their role in the crustal formation of the Pamirs?
� What are the eastern and western equivalents to Pamiran sutures and crustal
blocks?
� Where is intracontinental deformation, caused by the India-Asia collision,
concentrated in the southern Tien Shan and eastern Pamirs? How does
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