The NE Tajik Basin in Central Asia, compressed between the ranges of the Tien Shan in the north and the Pamir in the south, is a key region for understanding the evolution of these mountain systems. Erosion and deposition history of the NE Tajik Basin and the adjoining orogens since the late Oligocene is reflected in the sedimentary record.The sedimentary rocks of the NE Tajik Basin are composed of thick units of proximal braided river deposits. They reflect large fluvial plains extending from the margins of the Northern Pamir and the Southern Tien Shan mountains, but are not related to the established lithostratigraphic scheme. Almost all Oligocene–Pliocene synorogenic deposits of the NE Tajik Basin were derived from the northern Pamir ranges, except upper Miocene–Recent proximal deposits close to the active margin of the Tien Shan. Initial uplift in some areas of the SW Tien Shan since the Oligocene was followed by a phase of low-energy sedimentation and a predominance of the southern source area. Since the middle Miocene, erosion of the ranges has occurred with the proximal sedimentation of coarse fluvial deposits along the northern margin of the Tajik Basin.
Late Pleistocene societies throughout the northern hemisphere used mammoth and mastodon ivory not only for art and adornment, but also for tools, in particular projectile points. A comparative analysis of the mechanical properties of tusk dentine from woolly mammoth (Mammuthus primigenius) and African elephant (Loxodonta africana) reveals similar longitudinal stiffness values that are comparable to those of cervid antler compacta. The longitudinal bending strength and work of fracture of proboscidean ivory are very high owing to its substantial collagen content and specific microstructure. In permafrost, these properties can be fully retained for thousands of years. Owing to the unique combination of stiffness, toughness and size, ivory was obviously the most suitable osseous raw material for massive projectile points used in big game hunting.
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