TY - JOUR A1 - Licht, A. A1 - van Cappelle, M. A1 - Abels, Hemmo A. A1 - Ladant, J. -B. A1 - Trabucho-Alexandre, J. A1 - France-Lanord, C. A1 - Donnadieu, Y. A1 - Vandenberghe, J. A1 - Rigaudier, T. A1 - Lecuyer, C. A1 - Terry, D. A1 - Adriaens, R. A1 - Boura, A. A1 - Guo, Z. A1 - Soe, Aung Naing A1 - Quade, J. A1 - Dupont-Nivet, Guillaume A1 - Jaeger, J. -J. T1 - Asian monsoons in a late Eocene greenhouse world JF - Nature : the international weekly journal of science N2 - The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34Myrago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago. Y1 - 2014 U6 - https://doi.org/10.1038/nature13704 SN - 0028-0836 SN - 1476-4687 VL - 513 IS - 7519 SP - 501 EP - + PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Huang, Wentao A1 - van Hinsbergen, Douwe J. J. A1 - Lippert, Peter C. A1 - Guo, Zhaojie A1 - Dupont-Nivet, Guillaume T1 - Paleomagnetic tests of tectonic reconstructions of the India-Asia collision zone JF - Geophysical research letters N2 - Several solutions have been proposed to explain the long-standing kinematic observation that postcollisional upper crustal shortening within the Himalaya and Asia is much less than the magnitude of India-Asia convergence. Here we implement these hypotheses in global plate reconstructions and test paleolatitudes predicted by the global apparent polar wander path against independent, and the most robust paleomagnetic data. Our tests demonstrate that (1) reconstructed 600-750km postcollisional intra-Asian shortening is a minimum value; (2) a 52Ma collision age is only consistent with paleomagnetic data if intra-Asian shortening was 900km; a 56-58Ma collision age requires greater intra-Asian shortening; (3) collision ages of 34 or 65Ma incorrectly predict Late Cretaceous and Paleogene paleolatitudes of the Tibetan Himalaya (TH); and (4) Cretaceous counterclockwise rotation of India cannot explain the paleolatitudinal divergence between the TH and India. All hypotheses, regardless of collision age, require major Cretaceous extension within Greater India. KW - India-Asia collision KW - tectonic reconstruction KW - paleomagnetism Y1 - 2015 U6 - https://doi.org/10.1002/2015GL063749 SN - 0094-8276 SN - 1944-8007 VL - 42 IS - 8 SP - 2642 EP - 2649 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Yang, Wei A1 - Dupont-Nivet, Guillaume A1 - Jolivet, Marc A1 - Guo, Zhaojie A1 - Bougeois, Laurie A1 - Bosboom, Roderic A1 - Zhang, Ziya A1 - Zhu, Bei A1 - Heilbronn, Gloria T1 - Magnetostratigraphic record of the early evolution of the southwestern Tian Shan foreland basin (Ulugqat area), interactions with Pamir indentation and India-Asia collision JF - Tectonophysics : international journal of geotectonics and the geology and physics of the interior of the earth N2 - The Tian Shan range is an inherited intracontinental structure reactivated by the far-field effects of the India-Asia collision. A growing body of thermochronology and magnetostratigraphy datasets shows that the range grew through several tectonic pulses since similar to 25 Ma, however the early Cenozoic history remains poorly constrained. The time-lag between the Eocene India-Asia collision and the Miocene onset of Tian Shan exhumation is particularly enigmatic. This peculiar period is potentially recorded along the southwestern Tian Shan piedmont. There, late Eocene marine deposits of the proto-Paratethys epicontinental sea transition to continental foreland basin sediments of unknown age were recently dated. We provide magnetostratigraphic dating of these continental sediments from the 1700-m-thick Mine section integrated with previously published detrital apatite fission track and U/Pb zircon ages. The most likely correlation to the geomagnetic polarity time scale indicates an age span from 20.8 to 13.3 Ma with a marked increase in accumulation rates at 19-18 Ma. This implies that the entire Oligocene period is missing between the last marine and first continental sediments, as suggested by previous southwestern Tian Shan results. This differs from the southwestern Tarim basin where Eocene marine deposits are continuously overlain by late Eocene-Oligocene continental sediments. This supports a simple evolution model of the western Tarim basin with Eocene-Oligocene foreland basin activation to the south related to northward thrusting of the Kunlun Shan, followed by early Miocene activation of northern foreland basin related to overthrusting of the south Tian Shan. Our data also support southward propagation of the Tian Shan piedmont from 20 to 18 Ma that may relate to motion on the Talas Fergana Fault. The coeval activation of a major right-lateral strike-slip system allowing indentation of the Pamir Salient into the Tarim basin, suggests far-field deformation from the India-Asia collision zone affected the Tian Shan and the Talas Fergana fault by early Miocene. (C) 2015 Elsevier B.V. All rights reserved. KW - Magnetostratigraphy KW - Cenozoic KW - Tian Shan KW - Pamir KW - Tarim Basin KW - Tectonics Y1 - 2015 U6 - https://doi.org/10.1016/j.tecto.2015.01.003 SN - 0040-1951 SN - 1879-3266 VL - 644 SP - 122 EP - 137 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huang, Wentao A1 - van Hinsbergen, Douwe J. J. A1 - Maffione, Marco A1 - Orme, Devon A. A1 - Dupont-Nivet, Guillaume A1 - Guilmette, Carl A1 - Ding, Lin A1 - Guo, Zhaojie A1 - Kapp, Paul T1 - Lower Cretaceous Xigaze ophiolites formed in the Gangdese forearc: Evidence from paleomagnetism, sediment provenance, and stratigraphy JF - Earth & planetary science letters N2 - The India-Asia suture zone of southern Tibet exposes Lower Cretaceous Xigaze ophiolites and radiolarian cherts, and time-equivalent Asian-derived clastic forearc sedimentary rocks (Xigaze Group). These ophiolites have been interpreted to have formed in the forearc of the north-dipping subduction zone below Tibet that produced the Gangdese magmatic arc around 15-20 degrees N, or in the forearc of a subequatorial intra-oceanic subduction zone. To better constrain the latitude of the ophiolites, we carried out an integrated paleomagnetic, geochronologic and stratigraphical study on epi-ophiolitic radiolarites (Chongdui and Bainang sections), and Xigaze Group turbiditic sandstones unconformably overlying the ophiolite's mantle units (Sangsang section). Detrital zircon U-Pb geochronology of tuffaceous layers from the Chongdui section and sandstones of the Xigaze Group at the Sangsang section provides maximum depositional ages of 116.5 +/- 3.1 Ma and 128.8 +/- 3.4 Ma, respectively, for the Chongdui section and an Asian provenance signature for the Xigaze Group. Paleomagnetic analyses, integrated with rock magnetic experiments, indicate significant compaction-related inclination 'shallowing' of the remanence within the studied rocks. Two independent methods are applied for the inclination shallowing correction of the paleomagnetic directions from the Sangsang section, yielding consistent mean paleolatitudes of 16.2 degrees N 113 degrees N, 20.9 degrees N] and 16.8 degrees N [11.1 degrees N, 23.3 degrees N], respectively. These results are indistinguishable from recent paleolatitude estimates for the Gangdese arc in southern Tibet. Radiolarites from the Chongdui and Bainang sections yield low paleomagnetic inclinations that would suggest a sub-equatorial paleolatitude, but the distribution of the paleomagnetic directions in these rocks strongly suggests a low inclination bias by compaction. Our data indicate that spreading of the Xigaze ophiolite occurred in the Gangdese forearc, and formed the basement of the forearc strata. (C) 2015 Elsevier B.V. All rights reserved. KW - Xigaze ophiolite KW - sedimentary contact KW - paleomagnetism and rock magnetism KW - inclination shallowing Y1 - 2015 U6 - https://doi.org/10.1016/j.epsl.2015.01.032 SN - 0012-821X SN - 1385-013X VL - 415 SP - 142 EP - 153 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huang, Wentao A1 - Dupont-Nivet, Guillaume A1 - Lippert, Peter C. A1 - van Hinsbergen, Douwe J. J. A1 - Dekkers, Mark J. A1 - Waldrip, Ross A1 - Ganerod, Morgan A1 - Li, Xiaochun A1 - Guo, Zhaojie A1 - Kapp, Paul T1 - What was the Paleogene latitude of the Lhasa terrane? A reassessment of the geochronology and paleomagnetism of Linzizong volcanic rocks (Linzhou basin, Tibet) JF - Tectonics N2 - The Paleogene latitude of the Lhasa terrane (southern Tibet) can constrain the age of the onset of the India-Asia collision. Estimates for this latitude, however, vary from 5 degrees N to 30 degrees N, and thus, here, we reassess the geochronology and paleomagnetism of Paleogene volcanic rocks from the Linzizong Group in the Linzhou basin. The lower and upper parts of the section previously yielded particularly conflicting ages and paleolatitudes. We report consistent Ar-40/Ar-39 and U-Pb zircon dates of similar to 52Ma for the upper Linzizong, and Ar-40/Ar-39 dates (similar to 51Ma) from the lower Linzizong are significantly younger than U-Pb zircon dates (64-63Ma), suggesting that the lower Linzizong was thermally and/or chemically reset. Paleomagnetic results from 24 sites in lower Linzizong confirm a low apparent paleolatitude of similar to 5 degrees N, compared to the upper part (similar to 20 degrees N) and to underlying Cretaceous strata (similar to 20 degrees N). Detailed rock magnetic analyses, end-member modeling of magnetic components, and petrography from the lower and upper Linzizong indicate widespread secondary hematite in the lower Linzizong, whereas hematite is rare in upper Linzizong. Volcanic rocks of the lower Linzizong have been hydrothermally chemically remagnetized, whereas the upper Linzizong retains a primary remanence. We suggest that remagnetization was induced by acquisition of chemical and thermoviscous remanent magnetizations such that the shallow inclinations are an artifact of a tilt correction applied to a secondary remanence in lower Linzizong. We estimate that the Paleogene latitude of Lhasa terrane was 204 degrees N, consistent with previous results suggesting that India-Asia collision likely took place by similar to 52Ma at similar to 20 degrees N. KW - remagnetization KW - rock magnetism KW - geochronology KW - India-Asia collision Y1 - 2015 U6 - https://doi.org/10.1002/2014TC003787 SN - 0278-7407 SN - 1944-9194 VL - 34 IS - 3 SP - 594 EP - 622 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Huang, Wentao A1 - van Hinsbergen, Douwe J. J. A1 - Dekkers, Mark J. A1 - Garzanti, Eduardo A1 - Dupont-Nivet, Guillaume A1 - Lippert, Peter C. A1 - Li, Xiaochun A1 - Maffione, Marco A1 - Langereis, Cor G. A1 - Hu, Xiumian A1 - Guo, Zhaojie A1 - Kapp, Paul T1 - Paleolatitudes of the Tibetan Himalaya from primary and secondary magnetizations of Jurassic to Lower Cretaceous sedimentary rocks JF - Geochemistry, geophysics, geosystems N2 - The Tibetan Himalaya represents the northernmost continental unit of the Indian plate that collided with Asia in the Cenozoic. Paleomagnetic studies on the Tibetan Himalaya can help constrain the dimension and paleogeography of "Greater India,' the Indian plate lithosphere that subducted and underthrusted below Asia after initial collision. Here we present a paleomagnetic investigation of a Jurassic (limestones) and Lower Cretaceous (volcaniclastic sandstones) section of the Tibetan Himalaya. The limestones yielded positive fold test, showing a prefolding origin of the isolated remanent magnetizations. Detailed paleomagnetic analyses, rock magnetic tests, end-member modeling of acquisition curves of isothermal remanent magnetization, and petrographic investigation reveal that the magnetic carrier of the Jurassic limestones is authigenic magnetite, whereas the dominant magnetic carrier of the Lower Cretaceous volcaniclastic sandstones is detrital magnetite. Our observations lead us to conclude that the Jurassic limestones record a prefolding remagnetization, whereas the Lower Cretaceous volcaniclastic sandstones retain a primary remanence. The volcaniclastic sandstones yield an Early Cretaceous paleolatitude of 55.5 degrees S [52.5 degrees S, 58.6 degrees S] for the Tibetan Himalaya, suggesting it was part of the Indian continent at that time. The size of "Greater India' during Jurassic time cannot be estimated from these limestones. Instead, a paleolatitude of the Tibetan Himalaya of 23.8 degrees S [21.8 degrees S, 26.1 degrees S] during the remagnetization process is suggested. It is likely that the remagnetization, caused by the oxidation of early diagenetic pyrite to magnetite, was induced during 103-83 or 77-67 Ma. The inferred paleolatitudes at these two time intervals imply very different tectonic consequences for the Tibetan Himalaya. Y1 - 2015 U6 - https://doi.org/10.1002/2014GC005624 SN - 1525-2027 VL - 16 IS - 1 SP - 77 EP - 100 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Huang, Wentao A1 - Dupont-Nivet, Guillaume A1 - Lippert, Peter C. A1 - van Hinsbergen, Douwe J. J. A1 - Dekkers, Mark J. A1 - Guo, Zhaojie A1 - Waldrip, Ross A1 - Li, Xiaochun A1 - Zhang, Xiaoran A1 - Liu, Dongdong A1 - Kapp, Paul T1 - Can a primary remanence be retrieved from partially remagnetized Eocence volcanic rocks in the Nanmulin Basin (southern Tibet) to date the India-Asia collision? JF - Journal of geophysical research : Solid earth N2 - Paleomagnetic dating of the India-Asia collision hinges on determining the Paleogene latitude of the Lhasa terrane (southern Tibet). Reported latitudes range from 5 degrees N to 30 degrees N, however, leading to contrasting paleogeographic interpretations. Here we report new data from the Eocene Linzizong volcanic rocks in the Nanmulin Basin, which previously yielded data suggesting a low paleolatitude (similar to 10 degrees N). New zircon U-Pb dates indicate an age of similar to 52Ma. Negative fold tests, however, demonstrate that the isolated characteristic remanent magnetizations, with notably varying inclinations, are not primary. Rock magnetic analyses, end-member modeling of isothermal remanent magnetization acquisition curves, and petrographic observations are consistent with variable degrees of posttilting remagnetization due to low-temperature alteration of primary magmatic titanomagnetite and the formation of secondary pigmentary hematite that unblock simultaneously. Previously reported paleomagnetic data from the Nanmulin Basin implying low paleolatitude should thus not be used to estimate the time and latitude of the India-Asia collision. We show that the paleomagnetic inclinations vary linearly with the contribution of secondary hematite to saturation isothermal remanent magnetization. We tentatively propose a new method to recover a primary remanence with inclination of 38.1 degrees (35.7 degrees, 40.5 degrees) (95% significance) and a secondary remanence with inclination of 42.9 degrees (41.5 degrees,44.4 degrees) (95% significance). The paleolatitude defined by the modeled primary remanence21 degrees N (19.8 degrees N, 23.1 degrees N)is consistent with the regional compilation of published results from pristine volcanic rocks and sedimentary rocks of the upper Linzizong Group corrected for inclination shallowing. The start of the Tibetan Himalaya-Asia collision was situated at similar to 20 degrees N and took place by similar to 50Ma. KW - remagnetization KW - paleomagnetism applied to tectonics KW - rock and mineral magnetism KW - India-Asia collision Y1 - 2015 U6 - https://doi.org/10.1002/2014JB011599 SN - 2169-9313 SN - 2169-9356 VL - 120 IS - 1 SP - 42 EP - 66 PB - American Geophysical Union CY - Washington ER - TY - GEN A1 - Licht, Alexis A1 - Dupont-Nivet, Guillaume A1 - Pullen, Alex A1 - Kapp, Paul A1 - Abels, Hemmo A. A1 - Lai, Zulong A1 - Guo, ZhaoJie A1 - Abell, Jordan A1 - Giesler, Dominique T1 - Resilience of the Asian atmospheric circulation shown by paleogene dust provenance T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The onset of modern central Asian atmospheric circulation is traditionally linked to the interplay of surface uplift of the Mongolian and Tibetan-Himalayan orogens, retreat of the Paratethys sea from central Asia and Cenozoic global cooling. Although the role of these players has not yet been unravelled, the vast dust deposits of central China support the presence of arid conditions and modern atmospheric pathways for the last 25 million years (Myr). Here, we present provenance data from older (42-33 Myr) dust deposits, at a time when the Tibetan Plateau was less developed, the Paratethys sea still present in central Asia and atmospheric pCO(2) much higher. Our results show that dust sources and near-surface atmospheric circulation have changed little since at least 42 Myr. Our findings indicate that the locus of central Asian high pressures and concurrent aridity is a resilient feature only modulated by mountain building, global cooling and sea retreat. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1114 KW - Chinese Loess Plateau KW - last glacial maximum KW - Tibetan Plateau KW - Yellow-River KW - climate KW - basin KW - evolution KW - ardification KW - monsoons KW - desert Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436381 SN - 1866-8372 IS - 1114 ER - TY - JOUR A1 - Licht, Alexis A1 - Dupont-Nivet, Guillaume A1 - Pullen, A. A1 - Kapp, P. A1 - Abels, Hemmo A. A1 - Lai, Z. A1 - Guo, Z. A1 - Abell, Jordan A1 - Giesler, D. T1 - Resilience of the Asian atmospheric circulation shown by Paleogene dust provenance JF - Nature Communications N2 - The onset of modern central Asian atmospheric circulation is traditionally linked to the interplay of surface uplift of the Mongolian and Tibetan-Himalayan orogens, retreat of the Paratethys sea from central Asia and Cenozoic global cooling. Although the role of these players has not yet been unravelled, the vast dust deposits of central China support the presence of arid conditions and modern atmospheric pathways for the last 25 million years (Myr). Here, we present provenance data from older (42-33 Myr) dust deposits, at a time when the Tibetan Plateau was less developed, the Paratethys sea still present in central Asia and atmospheric pCO(2) much higher. Our results show that dust sources and near-surface atmospheric circulation have changed little since at least 42 Myr. Our findings indicate that the locus of central Asian high pressures and concurrent aridity is a resilient feature only modulated by mountain building, global cooling and sea retreat. Y1 - 2016 U6 - https://doi.org/10.1038/ncomms12390 SN - 2041-1723 VL - 7 SP - 885 EP - 894 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Han, Fang A1 - Rydin, Catarina A1 - Bolinder, Kristina A1 - Dupont-Nivet, Guillaume A1 - Abels, Hemmo A. A1 - Koutsodendris, Andreas A1 - Zhang, Kexin A1 - Hoorn, Carina T1 - Steppe development on the Northern Tibetan Plateau inferred from Paleogene ephedroid pollen JF - Grana N2 - Steppe vegetation represents a key marker of past Asian aridification and is associated with monsoonal intensification. Little is, however, known about the origin of this pre-Oligocene vegetation, its specific composition and how it changed over time and responded to climatic variations. Here, we describe the morphological characters of Ephedraceae pollen in Eocene strata of the Xining Basin and compare the pollen composition with the palynological composition of Late Cretaceous and Paleocene deposits of the Xining Basin and the Quaternary deposits of the Qaidam Basin. We find that the Late Cretaceous steppe was dominated by Gnetaceaepollenites; in the transition from the Cretaceous to the Paleocene, Gnetaceaepollenites became extinct and Ephedripites subgenus Ephedripites dominated the flora with rare occurrences of Ephedripites subgen. Distachyapites; the middle to late Eocene presents a strong increase of Ephedripites subgen. Distachyapites; and the Quaternary/Recent is marked by a significantly lower diversity of Ephedraceae (and Nitrariaceae) compared to the Eocene. In the modern landscape of China, only a fraction of the Paleogene species diversity of Ephedraceae remains and we propose that these alterations in Ephedreaceae composition occurred in response to the climatic changes at least since the Eocene. In particular, the strong Eocene monsoons that enhanced the continental aridification may have played an important role in the evolution of Ephedripites subgen. Distachyapites triggering an evolutionary shift to wind-pollination in this group. Conceivably, the Ephedraceae/Nitrariaceae dominated steppe ended during the Eocene/Oligocene climatic cooling and aridification, which favoured other plant taxa. KW - pollen morphology KW - Eocene KW - climate KW - Ephedripites KW - Distachyapites KW - Gnetaceaepollenites KW - monsoon Y1 - 2016 U6 - https://doi.org/10.1080/00173134.2015.1120343 SN - 0017-3134 SN - 1651-2049 VL - 55 SP - 71 EP - 100 PB - Springer CY - Oslo ER -