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Continental evolution is responsible for the evolution of orogenic belts and sedimentary basins. The India–Asia convergence during the late Mesozoic to Cenozoic and the resulting tectono-sedimentary processes in the Tibetan Plateau and and its environs are among the most spectacular manifestations of continental evolution and sedimentary basin formation in recent Earth history. The aim of this special issue is to explore continental evolution and sedimentary basins in central-southern Asia since the late Mesozoic, with a main focus on the India–Asia convergence and the resulting tectono-sedimentary, tectono-geomorphologic, and paleoclimatic/paleoenvironmental processes in the Tibetan Plateau and its environs during the late Cretaceous to Neogene. The issue comprises ten papers that address the significance of Continental Evolution and Sedimentary Basins of the Tibetan Plateau and its Environs since the middle Cretaceous, and that fall into three categories. (i) The first category addresses the paleogeography of the southern-central Tibetan Plateau during the Cretaceous to Paleogene. These studies decipher the multistage collision of India with Asia, the opening and closing of ocean basins, and the tectonic evolution of the major blocks (such as Tibetan Himalaya, Lhasa, and southern/western Qiangtang) and especially of the major Himalayan tectonostratigraphic units during the convergence history between India and Asia. (ii) The second category addresses the tectono-sedimentary and tectono-geomorphologic evolution of the eastern and northeastern margins of the Tibetan Plateau during the late Cretaceous to Neogene. (iii) The third and the final category addresses the tectono-sedimentary basin filling and/or paleoenvironmental processes during the late Eocene to Pliocene, which are recorded in the intermontane Kuche and Tajik basins in central Asia and thus may reflect the far-field influence of the post-collisional India–Asia convergence on these sedimentary basins. • Continental evolution is responsible for the evolution of orogenic belts and sedimentary basins. The India–Asia convergence during the late Mesozoic to Cenozoic and the resulting tectono-sedimentary processes in the Tibetan Plateau and and its environs are among the most spectacular manifestations of continental evolution and sedimentary basin formation in recent Earth history. • The paleogeography of the southern-central Tibetan Plateau during the Cretaceous to Paleogene was shaped by the multistage collision of Inida with Asia, the opening and closing of ocean basins, and the tectonic evolution of the major blocks (such as Tibetan Himalaya, Lhasa, and southern/western Qiangtang) and especially of the major Himalayan tectonostratigraphic units during the convergence history between India and Asia. • The India–Asia collision and ongoing convergence led to southeastward crustal extrusion, eastward and northeastward crustal growth and expansion of the Tibetan Plateau, and widespread crustal deformation surrounding the plateau. The concurrent uplift, denudation, and sedimentation have played important roles in shaping the mountain topography of the orogenic plateau margins. • The tectono-sedimentary filling and/or paleoenvironmental processes recorded in the intermontane Kuche and Tajik basins in central Asia during the late Eocene to Pliocene may reflect the far-field influence of the post-collisional India–Asia convergence on the sedimentary basins in central Asia and/or the interplay between tectonics and climate in the Asian interior. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge of the Little Ice Age (LIA) on the Tibetan Plateau (TP) is of critical importance for understanding the climate changes over the past millennium. However, the data associated with the extents and chronologies of TP LIA moraines are highly dispersed in literature. Lack of systematic integration of these data hampers us to further understand the nature of the LIA, especially from a perspective of whole TP. The paper reviews multiple types of dating on LIA moraines to examine the timing and nature of the LIA on the TP. These include ages of radiocarbon 14C, lichenometry, and cosmogenic radionuclide (CRN), by which we can cross-date the same or morphostratigraphically similar landforms. LIA moraines on the TP are usually present a few hundred to thousand meters beyond the contemporary glaciers. The morphological and stratigraphic evidence indicates multiple periods of glacier advance during the last millennium (LIA). At present, available chronology evidence allows to fully compare the timing of the LIA maximum extents. The glaciers reached and retreated from their LIA maximum extents by an asynchronous pattern between different parts of the TP. The majority of glaciers advanced to their LIA maximum extents at late-14th and early-14th century on the southern and northwestern TP, respectively. The glaciers retreated from their LIA maximum extents during 16th to early-18th, late-14th to early-15th and early-16th century on the southern, northwestern, and northeastern TP, respectively. In addition, the glacier advance period of late-18th to early-19th centuries and retreat period of late-19th century are common on the whole TP. Comparison with ice core records suggests that on the TP, the glacier fluctuations responded more strongly to temperature than to precipitation. By comparison of the LIA chronologies from a global perspective, this paper also concludes that the LIA maximum extents occurred commonly earlier on the TP than in North Atlantic and Southern Hemisphere regions, despite of the variability in the timing of LIA maximum extents on the TP and in the North Atlantic regions. Further, more chronology programs, especially in the central TP, are necessarily needed to improve our understanding of the LIA glacier fluctuations. [Copyright &y& Elsevier]

Two atmospheric circulation systems, i.e., the mid-latitude Westerlies and the East Asian summer monsoon (EASM), dominate climate change in the NE Tibetan Plateau. However, controversy remains with regard to the climatic boundary between these westerly and monsoon regimes. In this paper, detailed rock magnetic and geochemical Rb/Sr analyses for a larger number of surface soils from a wide area in the NE Tibetan Plateau are presented. They show that surface soils in this region evince relatively significant regional variations in magnetic properties and geochemical characteristics. The magnetic parameters χ fd, χ ARM and geochemical Rb/Sr ratios exhibit higher values in EASM-controlled (humid) areas, and lower values in Westerlies-influenced (arid) areas. These characteristics indicate that such variations in χ fd, χ ARM and Rb/Sr ratios can be regarded as effective indicators of the degree of pedogenesis and weathering in the NE Tibetan Plateau. Our results also demonstrate that the climatic boundary between the westerly and monsoon regimes approximately overlaps with the boundary of highland meadow and temperate steppe desert/desert in NW China. [ABSTRACT FROM AUTHOR]

Carbon and hydrogen isotopic compositions of leaf wax n -alkanes are promising paleoelevation proxies. In this paper, the two proxies were applied to the Dingqing Formation in the Lunpola basin in the central Tibetan Plateau to reconstruct paleoelevation of the basin from the latest Oligocene to the early Miocene. Values of δ 13 C and δD of C 29 n -alkane were − 29.8 ± 0.7 ‰ ( n = 38) and − 188 ± 10 ‰ ( n = 22), respectively. Using the δ 13 C and δ 18 O of the early Miocene Siwalik paleosol carbonate in south Asia as lowland references, paleoelevation of ~ 3000 m was independently estimated from the two isotopic proxies. The results are consistent with recent estimates from pollen and mammal fossil studies. Furthermore, the time-series leaf wax δ 13 C and δD records consistently suggest a reduction of ~ 900 m from 25.5 Ma to 21.6 Ma, which is likely associated with rapid erosion or tectonic unroofing. [ABSTRACT FROM AUTHOR]

Climate on the Tibetan Plateau is often considered sensitive to global changes, yet the degree of sensitivity in different spaces and seasons prior to instrumental records is not clear. In this paper, we studied tree-ring maximum latewood density (MXD) to examine the late-summer (August–September) temperature variation over the past two and half centuries on the eastern Tibetan Plateau. The MXD regional chronology was established from 109 tree-ring samples of Balfour spruce [ Picea likiangensis var. balfouriana (Rehd. et Wils.)] at four high elevation sites. The chronology exhibited a high correlation ( r = 0.82, n = 56, p < 0.001) with the mean August–September temperature. Using the tree-ring data, we reconstructed the late-summer temperature for the period A.D. 1765–2009. The reconstruction accounted for 71.4% of the variance in instrumental temperature in the period 1954–2009. The reconstructed temperature did not show a warming trend in the past 250 years, suggesting a unique characteristic of late-summer temperature variability in the study region of the Tibetan Plateau. Our tree-ring data are useful for further understanding of the plateau's thermal condition in late summer and its role in regulating southward retreat of the Southwest Asian monsoon. [ABSTRACT FROM AUTHOR]