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| 1 | Nd isotopic compositions of the Tethyan Himalayan Sequence in southeastern Tibet显示文摘The Himalayan orogen consists of three major lithologic units that are separated by two major north-dipping faults: the Lesser Himalayan Sequence (LHS) below the Main Central Thrust (MCT), the Greater Himalayan Crystalline Complex (GHC) above the MCT, and the Tethyan Himalayan Sequence (THS) juxtaposed by the South Tibet Detachment fault (STD) over the GHC. Due to widespread meta-morphism and intense deformation, differentiating the above three lithologic units is often difficult. This problem has been overcome by the use of Sm-Nd isotopic analysis. The previous studies suggested that the LHS can be clearly distinguished from the GHC and THS by their Nd isotope compositions. However, the lack of detailed and systematic Sm-Nd isotopic studies of the THS across the Himalaya in general has made differentiation of this unit from the nearby GHC impossible, as the two appear to share overlapping Nd compositions and model ages. To address this problem, we systematically sam-pled and analyzed Nd isotopes of the THS in southeastern Tibet directly north of Bhutan. Our study identifies two distinctive fields in a εNd -TDM plot. The first is defined by the εNd(210 Ma) values of -3.45 to -7.34 and TDM values of 1.15 to 1.29 Ga from a Late Triassic turbidite sequence, which are broadly similar to those obtained from the Lhasa block. The second field is derived from the Early Cretaceous meta-sedimentary rocks with εNd(130 Ma) values from -15.24 to -16.61 and TDM values from 1.63 to 2.00 Ga; these values are similar to those obtained from the Greater Himalayan Crystalline Complex in Bhutan directly south of our sampling traverse, which has εNd(130 Ma) values of -10.89 to -16.32 and Nd model ages (TDM) of 1.73 to 2.20 Ga. From the above observations, we suggest that the Late Triassic strata of the southeast Tibetan THS were derived from the Lhasa block in the north, while the Early Cretaceous strata of the THS were derived from a source similar to the High Himalayan Crystalline Complex or Indian craton in the south. Our interpretation is consistent with the existing palaeocurrent data and provenance analysis of the Late Triassic strata in southeastern Tibet, which indicate the sediments derived from a northern source. Thus, we suggest that the Lhasa terrane and the Indian craton were close to one another in the Late Triassic and were separated by a rift valley across which a large submarine fan was transported southward and deposited on the future northern margin of the Indian continent. | DAI JinGen YIN An LIU WenCan WANG ChengShan | 2008 | Science China Earth Sciences2008，51，9： | 19 |
| 2 | Middle Jurassic-early Cretaceous radiolarian assemblages of the western Yarlung Zangbo Suture Zone: Implications for the evolution of the Neo-Tethys显示文摘Cherts in the Zhongba melange of the western Yarlung Zangbo Suture Zone(YZSZ) contain well preserved radiolarian assemblages. These radiolarian assemblages indicate that the Zhongba melange has middle Jurassic-early Cretaceous remnant, are coeval with those from the central and eastern parts of the YZSZ. Cherts from the Najiu area yield Aalenian to Aptian radiolarians, while cherts interbedded with siliceous mudstones from the Bielongjiala area yield Aptian radiolarians, indicating that terrigenousderived sediments were deposited during early Aptian. The above observations indicate that the entire YZSZ have a similar geochronological framework and thus they underwent similar geological evolution:(1) during the Jurassic, the Neo-Tethys was a wide ocean with pelagic sediments distal from continents;(2) during the Cretaceous(around 130-120 Ma), the Neo-Tethys started to subduct along the southern margin of the Lhasa block, and terrigenous-derived siliceous mudstone began deposition. | Hanting Zhong Jingen Dai Chengshan Wang Yalin Li Yushuai Wei | 2017 | Geoscience Frontiers2017，8，5： | 6 |
| 3 | Simulation and optimization for a 30-MeV electron accelerator driven neutron source显示文摘A neutron source driven by electron accelerator is proposed in Shanghai Institute of Applied Physics (SINAP). The facility is planned for the study of nuclear data in Thorium-Uranium cycling system, and for material research. A detailed simulation of the neutron source is performed for the program to get the neutron generation maximum economically. Several parameters of the facility, which affect the neutron yield and the neutron escape from outer surface of the target, are analyzed respectively. Besides, the yielding neutron spectrum and the escaping neutron angular distribution are calculated and discussed. | LIN Zuokang SUN Guomin CHEN Jingen LIU Guimin DAI Zhimin | 2012 | Nuclear Science and Techniques2012，23，5： | 4 |
| 4 | Outward-growth of the Tibetan Plateau during the Cenozoic: A review显示文摘 | Chengshan Wang Jingen Dai Xixi Zhao Yalin Li Stephan A. Graham Dengfa He Bo Ran Jun Meng | 2014 | Tectonophysics2014，，： | 1 |
| 5 | The vast proto-Tibetan Plateau:New constraints from Paleogene Hoh Xil Basin 显示文摘 | Dai Jingen Zhao Xixi Wang Chengshan | 2012 | Gond- wana Research2012，22，2： | 1 |
| 6 | Sedimentology,provenance and geochronology of the Miocene Qiuwu Formation:Implication for the uplift history of Southern Tibet显示文摘Located on the south of the Gangdese,the Qiuwu Formation has traditionally been considered as Eocene coal-bearing clastic sediments consisting of sandstone,mudstone and conglomerate,unconformably on top of Gangdese batholith.However,its precise age and depositional environment remain ambiguous.Here,we present a newly measured stratigraphic section near the Ngamring County,western Xigaze.Detrital zircon U-Pb ages were also applied to trace the provenance of sediments and to constrain the maximum depositional age of the Qiuwu Formation.Sedimentary facies analyses indicate subaqueous fan and alluvial fan depositional environments.Clast composition of the conglomerate is dominated by magmatic rocks at the lower part,while chert and mafic detritus occur in the upper part,suggesting a southern source.Sandstone modal analyses indicate that the compositions of quartz,feldspar and lithic grains changed from transitional arc to dissected arc,implying the unroofing of the Gangdese arc.Detrital zircon U-Pb ages of the Qiuwu Formation are compared with those from Gangdese magmatic rocks and Yarlung-Zangbo ophiolites,suggesting that the Gangdese arc is a main source of the Qiuwu detritus and that the southern source played a role during the later stage.The major peak of detrital zircon ages is at 45-55 Ma,which corresponds to Linzizong volcanic rocks in southern Gangdese arc.The weighted mean age of the five youngest zircons from the lower part of the section is 21.0 ± 2.2 Ma,suggesting that the Qiuwu Formation was deposited in early Miocene,coeval with other conglomerates exposed along the southern margin of Gangdese.Combining new observations with previously published data,we propose that the provenance of the Qiuwu Formation had shifted from a single northern source to double sources from both the north and the south.Activities of Great Counter Thrust were primarily responsible for the shift by making the south area a high elevation to provide sediments for the Qiuwu Formation. | Jiawei Zhang Jingen Dai Xinyu Qian Yukui Ge Chengshan Wang | 2017 | Geoscience Frontiers2017，8，4： | 0 |
| 7 | Subduction Initiation and Generation of the Xigaze Ophiolite, Southern Tibet显示文摘The Cretaceous Xigaze ophiolite is best exposed at the central Yarlung Zangbo Suture Zone(YZSZ,Tibet)which also includes the Gangdese arc and the Xigaze forearc basin.This study reports new geochronological and geochemical data for this ophiolite to revisit its geodynamic and petrogenetic evolution.The | DAI Jingen WANG Chengshan Zhu Dicheng POLAT Ali LI Yalin | 2015 | Acta Geologica Sinica(English Edition)2015，89，A02： | 0 |
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