22 results
Search Results
2. Response of Zhadang Glacier runoff in Nam Co Basin, Tibet, to changes in air temperature and precipitation form.
- Author
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ZHOU ShiQiao, KANG ShiChang, GAO TanGuang, and ZHANG GuoShuai
- Subjects
GLACIERS ,RUNOFF ,GEOLOGICAL basins ,ATMOSPHERIC temperature ,METEOROLOGICAL precipitation ,CLIMATE change - Abstract
This paper describes 2007/2008 inter-annual changes in runoff from the Zhadang Glacier located on the northern slope of Nyainqêntanglha Range, Tibet, and analyzes their causes. Precipitation increased by 17.9% in summer months of 2008 compared with the same period in 2007, drainage basin runoff decreased by 33.3%, and glacial meltwater decreased by 53.8%. Change in positive accumulated air temperature explained approximately half of the inter-annual difference in glacial meltwater using a degree-day model. This suggests that the glacier is extremely sensitive to changes in air temperature. Energy balance analysis showed that change in glacier surface albedo, considered to be caused by difference in precipitation form, resulted in the large inter-annual difference in glacial meltwater. It was shown statistically that precipitation form in the summer months of 2007 was mainly rainfall which comprised 71.5% of total precipitation, while during the same period in 2008 rainfall accounted for 30.7%, with the majority of precipitation falling as snow. Precipitation form should be considered an independent factor when analyzing glacier sensitivity to climate change or forecasting the runoff from certain glaciers. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
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3. The first discovery of Permian conodont fauna from peri-Gondwana cool water facies in Tibet, China.
- Author
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Zheng Youye, Xu Rongke, Wang Chengyuan, and Ma Guolao
- Subjects
PERMIANS ,CONODONTS ,ANIMALS ,MARINE sediments ,TETHYS (Paleogeography) - Abstract
The Angjie Formation and Xiala Formation, present in the Shiquanhe area of Gar County in the western part of Gangdise, Tibet, belong to the Gangdise stratigraphic subregion. Conodonts have been found in the Angjie Formation, and they permit an age determination of Early to Middle Permian for that formation. The age of the Xiala Formation could be late Middle Permian. Whether the Late Permian marine deposits are present in this area still needs to be determined, but it is possible that the lower part of the Xiala Formation overlaps partly the upper part of the Angjie Formation. More importantly, the study has brought about a finding of typical peri-Gondwana cool water facies conodonts, namely, Vjalovognathus sp. nov. x. This is the first report and brief description of a conodont fauna from peri-Gondowana cool water facies in China. It indicates that the Gangdise stratigraphic subregion can be subdivided; the western part belongs to peri-Gondwana cool water facies, and the eastern part belongs to Tethys. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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4. Rapid denudation of the Himalayan orogen in the Nyalam area, southern Tibet, since the Pliocene and implications for tectonics-climate coupling.
- Author
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Zheng, Yong, Zhang, Jinjiang, Wang, Jiamin, Zhang, Bo, Wang, Xiaoxian, and Wang, Meng
- Subjects
CHEMICAL denudation ,OROGENIC belts ,PLIOCENE Epoch ,PLATE tectonics - Abstract
The Himalayan orogen characterized by very high variability in tectonic and climatic processes, and is thus regarded as a natural laboratory for investigating the coupling of tectonics and climate, as well as the influence of this coupling on geomorphological processes. This study uses apatite fission track (AFT) dating of samples from a 45-km-long section crossing the Great Himalaya Crystalline Complex (GHC) in the Nyalam area, southern Tibet, to constrain the timing and rate of late Cenozoic denudation. The AFT ages can be divided into two groups: (1) 15-6 Ma, to the north of Nyalam town, for which the best-fit line of elevation-age has a gentle slope of 0.05, and for which a denudation rate of 0.27 mm/a is calculated; and (2) 3-1 Ma, south of Nyalam town, for which the best-fit line has a steep slope of 0.64, and for which a denudation rate of 1.32 mm/a is calculated. The whole AFT ages has a positive correlation with sample elevation (i.e., older ages are found at higher elevations), and the geographical location of the point of inflexion of the two fitted lines corresponds closely to the junction of Poqu River near Nyalam town. By integrating the AFT data with thermo-tectonic modeling, it can be inferred that the GHC has experienced two different periods of denudation: (1) slow denudation during middle to late Miocene (15-6 Ma) is recorded in the northern part of the GHC; and (2) rapid denudation from the Pliocene to the Pleistocene (3-1 Ma) is recorded in the southern part of the GHC. An abrupt change in denudation rate occurred between the two periods, with the Pliocene-Pleistocene denudation rate being five times higher than that during the Miocene. This abrupt change in denudation rate during Pliocene pervaded the Himalayan orogen, and was roughly synchronous with a marked change in global climate at 4-3 Ma, and intensification of the Asian monsoon. Importantly, the later period of rapid denudation in the study region closely coupled to the mean annual precipitation, while there is no clear evidence for large-scale faulting activity and associated uplift during this period. Therefore, climate (precipitation) is inferred to be the main cause of the rapid denudation of the Himalayan orogen since the Pliocene. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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5. Ranging pattern and population composition of Rhinopithecus bieti at Xiaochangdu, Tibet: Implications for conservation.
- Author
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Xiang, ZuoFu, Xiao, Wen, Huo, Sheng, and Li, Ming
- Subjects
RHINOPITHECUS ,WILDLIFE conservation ,ANIMAL populations ,BIOMASS ,SPATIO-temporal variation ,MONKEY behavior - Abstract
We studied the ranging pattern of the wild black-and-white snub-nosed monkeys ( Rhinopithecus bieti) at Xiaochangdu, Tibet from June 2003 to March 2005. Using the map grid cell method, the group home range were 16.75 km in summer, 10.50 km in winter, and 21.25 km total over two years. The daily travel length (DTL) averaged 765 m with a range of 350-3500 m. The results showed that DTL in winter was significantly shorter than those of in summer and spring. Temperature, rainfall, food availability, and human disturbance correlated positively with DTL. According to the maximum observed group size and estimated total home range, population density and biomass of R. bieti were 9.1 individuals/km and 88.6 kg/km, respectively. The temporal and spatial variations of food resources and patterns of human disturbance largely determine the ranging behavior of R. bieti at Xiaochangdu. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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6. Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications.
- Author
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Huang, QiShuai, Shi, RenDeng, Liu, DeLiang, Zhang, XiaoRan, Fan, ShuaiQuan, and Ding, Lin
- Subjects
OPHIOLITES ,LITHOSPHERE ,METAMORPHISM (Geology) ,CHEMICAL weathering ,OCEANIC crust ,MESOZOIC stratigraphic geology ,DUNITE ,EARTH'S mantle ,EARTH (Planet) - Abstract
Early-crystallizing chromian spinel (Cr-spinel) in the Nagqu ophiolite has high Os and low Re contents, and it is resistant to alteration during serpentinization, weathering and metamorphism. The chemical composition of primitive magma is preserved in Cr-spinel, which makes it suitable for determining the initial Os-isotope composition of the mantle source. This study presents Cr-spinel Os isotopes and zircon U-Pb ages for cumulate dunite and gabbro, respectively, in the same cumulate section of the ophiolite at Nagqu in Tibet. The results shed light on the formation and evolution of lithospheric mantle. The Nagqu ophiolite is located in the central part of the Bangong-Nujiang suture zone. It is a remnant of the Neotethyan oceanic crust, and contains cumulate dunite and gabbro. Zircon from the gabbro yielded a weighted mean Pb/U age of 183.7±1 Ma. Cr-spinel exhibits γ values of −0.2 to −0.3, suggesting that the mantle source for the dunite is similar to that of carbonaceous chondrites. Thus, the Tibetan lithosphere is primarily a relic of Tethyan oceanic lithosphere, which has formed by the transformation of the normal asthenospheric mantle in the Mesozoic. This is the first study to combine the spinel Os isotopes with accurate zircon U-Pb ages to constrain the geochemical characteristics of the mantle source for the ophiolite. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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7. Mapping wetland changes in China between 1978 and 2008.
- Author
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Niu, ZhenGuo, Zhang, HaiYing, Wang, XianWei, Yao, WenBo, Zhou, DeMin, Zhao, KuiYi, Zhao, Hui, Li, NaNa, Huang, HuaBing, Li, CongCong, Yang, Jun, Liu, CaiXia, Liu, Shuang, Wang, Lin, Li, Zhan, Yang, ZhenZhong, Qiao, Fei, Zheng, YaoMin, Chen, YanLei, and Sheng, YongWei
- Subjects
GLOBAL environmental change ,REMOTE sensing ,ENVIRONMENTAL mapping ,WETLAND mapping ,MARSHES - Abstract
Four wetland maps for all China have been produced, based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978, 1990, 2000 and 2008). These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009. Based on these maps, we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years. (i) There were about 324097 km of wetlands in 2008, for which inland marshes or swamps were the most common wetland type (35%), with lakes (26%) second. Most of the wetlands were in Heilongjiang, Inner Mongolia, Qinghai and Tibet, occupying about 55% of the national wetland area. (ii) From 1978 to 2008, China's wetland area continually and significantly decreased, by about 33% based on changes in the wetland map. This was in sharp contrast to the increase in artificial wetlands, which increased by about 122%. Inland marshes accounted for the main loss of total wetlands from 1978 to 2000. From 2000 through 2008, riverine and lacustrine wetlands constituted the main wetland loss. Fortunately however, the rate of wetland loss decreased from 5523 to 831 km/a. (iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years. From 1978 to 1990, nearly all natural wetlands (98%) lost were transformed into non-wetlands. However, the ratio declined to 86% from 1990 to 2000, and to 77% from 2000 to 2008. (iv) All Chinese provinces were divided into three groups according to patterns of wetland changes, which could relate to the driving forces of such changes. Tibet was completely different from other provinces, as it was one representative example in which there was a net wetland increase, because of global warming and decreased human activity since 1990. Increased economic development caused considerable wetland loss in most eastern provinces, and artificial wetlands increased. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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8. Eocene high grade metamorphism and crustal anatexis in the North Himalaya Gneiss Domes, Southern Tibet.
- Author
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Gao, LiE, Zeng, LingSen, and Xie, KeJia
- Subjects
METAMORPHISM (Geology) ,AMPHIBOLITES ,GRANULITE ,METAMORPHIC rocks ,GNEISS - Abstract
Determination of the timing and geochemical nature of early metamorphic and anatectic events in the Himalayan orogen may provide key insights into the physical and chemical behavior of lower crustal materials during the early stage of tectonic evolution in large-scale collisional belts. The Yardoi gneiss dome is the easternmost dome of the North Himalayan Gneiss Domes (NHGD), and contains three types of amphibolites with distinct mineral assemblage, elemental and radiogenic isotope geochemistry, as well as various types of gneisses. SHRIMP zircon U/Pb analyses on the garnet amphibolite and garnet-bearing biotite granitic gneiss yield ages of nearly peak metamorphism at 45.0±1.0 Ma and 47.±1.8 Ma, respectively, which are 2 to 4 Ma older than the age for partial melting in migmatitic garnet amphibolite (43.5±1.3 Ma). Available data have demonstrated that ultra-high pressure metamorphism in the Tethyan Himalaya occurred at ∼55 Ma, and high amphibolite facies to granulite facies metamorphism at 45 to 47 Ma. In addition, partial melting at thickened crustal conditions occurred at 43.5±1.3 Ma, which led to the formation of high Sr/Y ratios two-mica granites. The high-grade metamorphic rocks in the NHGD may represent the subducted front of the Indian continental lithosphere. In large collisional belts, fertile components in crustal materials could melt and form granitic melts with relatively high Na/K and Sr/Y ratios under thickened crustal conditions, significantly different from those formed by decompressional melting during rapid exhumation. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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9. Finding of high-pressure mafic granulites in the Amdo basement, central Tibet.
- Author
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ZHANG XiaoRan, SHI RenDeng, HUANG QiShuai, LIU DeLiang, CIDAN SuoLang, YANG JingSui, and DING Lin
- Subjects
GRANULITE ,HIGH pressure (Science) ,MINERALS ,PYROXENE ,ATMOSPHERIC temperature ,METAMORPHISM (Geology) - Abstract
High-pressure mafic granulites with a peak mineral assemblage of garnet + clinopyroxene + rutile + quartz were found in the Amdo basement, central Tibet. Two kinds of symplectites were identified that are composed of orthopyroxene + plagioclase ± spinel and hornblende + plagioclase around garnet, which were interpreted to develop during the retrogressing stages in the granulites. P-T estimates suggested that peak metamorphic conditions were about 860--920°C and 1.46--1.56 GPa, which retrogressed from post-peak phase at 820--890°C and 0.88--1.15 GPa to amphibolite facies at 550--670°C and 0.52--0.65 GPa. These three stages define a clockwise P-T path with near-isothermal decompression and cooling following the peak high-pressure metamorphism. This suggests that the Amdo granulites underwent an initial subduction to a deep crustal level of ~50 km and then were rapidly exhumed to a shallow crustal level (~20 km). The formation of Amdo granulites is considered to result from the arc-continent collision between the Amdo basement and the Qiangtang terrane in the middle Jurassic, which is a crucial step to the tectonic evolution of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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10. Concentration and seasonal variation of 10Be in surface aerosols of Lhasa, Tibet.
- Author
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HUANG Jie, KANG ShiChang, SHEN ChengDe, CONG ZhiYuan, LIU KeXin, WANG Wei, and LIU LiChao
- Subjects
BERYLLIUM isotopes ,AEROSOLS ,STRATOSPHERE ,TROPOSPHERE ,STATISTICAL correlation - Abstract
Thirty samples of total suspended particles were collected at a site in western part of Lhasa, Tibet from August 2006 to July 2007. The
10 Be concentrations were determined by Accelerator Mass Spectrometer (AMS). Analysis of correlation between10 Be concentrations and meteorological factors revealed that the wet scavenging has little effect on10 Be.10 Be can be used as a proxy of 10 transport processes of the upper atmosphere over the Tibetan Plateau. Analysis of correlation between10 Be concentrations and NCEP reanalysis data demonstrated that higher10 Be concentrations in spring were probably caused by the atmosphere exchange from stratosphere to troposphere during February to June. Lower10 Be concentrations during August to September were consistent with the synchronous lower O3 values, suggestive of both10 Be and O3 were probably influenced by the atmosphere exchange from troposphere to stratosphere. [ABSTRACT FROM AUTHOR]- Published
- 2010
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11. Locating seismic scatterers at the base of the mantle beneath eastern Tibet with PKIKP precursors.
- Author
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Shen XuZhang and Zhou HuiLan
- Subjects
GEODETIC astronomy ,SEISMIC arrays ,AZIMUTH ,GEOPHYSICAL instruments - Abstract
Clear PKIKP precursors were observed from the Lanzhou CTBTO seismic array. We measured their incident angles, arriving azimuths and differential travel times with respect to the PKIKP arrivals using array analysis techniques. These measurements allowed us to locate the scatterers that generated the observed precursors. We found that the scatterers are located in the lowermost mantle beneath eastern Tibet, which is featured by a high-velocity anomaly based on previous tomographic studies. The high velocity anomaly was interpreted as the slab remnants of the ancient Tethys subduction. We thus speculate that the observed scatterers are either related or induced by the subducted slab. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
12. SHRIMP U-Pb dating and Hf isotopic analyses of zircons from the mafic dyke swarms in central Qiangtang area, Northern Tibet.
- Author
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Zhai Qing Guo, LI Cai, Wang Jun, JI Zhan Sheng, and Wang Yong
- Subjects
GEOCHRONOMETRY ,ZIRCONIUM isotopes ,ZIRCON ,EARTHQUAKE swarms ,DIKES (Geology) - Abstract
In the "Central Uplift" of Qiangtang, Northern Tibet, a large scale of mafic dyke swarms extended in E-W direction. Zircon SHRIMP U-Pb dating on two representative samples of diabase dyke yield weighted mean ages of 284 ± 3 Ma and 302 ± 4 Ma, respectively, suggesting they emplaced in the Late Carboniferous to Early Permian. Zircon
176 Hf/177 Hf ratios range from 0.282852 to 0.283041, withϵHf (f) values of +12.1 to +12.2 and Hf modal (TDM ) ages of -440-460 Ma. These data indicate that these mafic dykes were mainly derived from the depleted mantle. In addition, geochemical data suggest that these mat ic dyke swarms are of intra-plate origin. Therefore, the mafic dyke swarms represent products during the extensional process associated with the opening of the Paleo-Tethys Ocean in the area. [ABSTRACT FROM AUTHOR]- Published
- 2009
- Full Text
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13. Geochronologic constraints on magmatic intrusions and mineralization of the Zhunuo porphyry copper deposit in Gangdese, Tibet.
- Author
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YouYe Zheng, GangYang Zhang, RongKe Xu, ShunBao Gao, YingChun Pang, Liang Cao, AnDao Du, and YuRuo Shi
- Subjects
BIOMINERALIZATION ,PORPHYRY ,COPPER - Abstract
In situ zircon U-Pb ages for the recently discovered Zhunuo porphyry copper deposit in the western part of the Gangdese metallogenic belt in Tibet were determined by sensitive high-resolution ion microprobe (SHRIMP). The ages can be divided into two separate groups, reflecting more than four major tectono-magmatic events in the area. The 62.5±2.5 Ma age of inherited zircons may be related to the volcanic eruption of the Linzizong Group formed shortly after the India-Asia continental collision. The 50.1±3.6 Ma age most likely corresponds to the time of underplating of mantle-derived mafic magma in Gangdese. The 15.6±0.6 Ma age obtained from magmatic zircons is interpreted as the age of crystallization of the Zhunuo ore-forming porphyry. Finally, a molybdenite Re-Os isochron age of 13.72±0.62 Ma is consistent with another zircon U-Pb age of 13.3 ±0.2 Ma, representing the time of copper mineralization. These ages, in combination with available literature data, indicate that magmatic crystallization and copper mineralization in the Gangdese metallogenic belt became gradually younger westward, and further suggest that the Zhunuo porphyry copper deposit was formed in the same tectonic stage as other porphyry copper deposits in the eastern and central Gangdese belt. This conclusion provides critical information for future exploration of porphyry copper deposits in western Gangdese. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
14. Cesium accumulation by bacterium Thermus sp. TibetanG7: hints for biomineralization of cesium-bearing geyserite in hot springs in Tibet, China.
- Author
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Wang HaiLei, Zheng MianPing, and Huang XiaoXing
- Subjects
BIOMINERALIZATION ,HOT springs ,CESIUM ,HYDROGEN-ion concentration - Abstract
The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, China, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K
+ , Na+ and K+ -regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K+ and Na+ , the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.49 and 40.41 μmol Cesium/g cell dry weight in Na+ and K+ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 40%-50% accumulated within the first 5 min. K+ -deficient cells showed a much higher capacity of cesium accumulation compared with K+ -sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered. [ABSTRACT FROM AUTHOR]- Published
- 2007
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15. Characteristics of Early Eocene radiolarian assemblages of the Saga area, southern Tibet and their constraint on the closure history of the Tethys.
- Author
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Li Yalin, Wang Chengshan, Hu Xiumian, M. Bak, Wang Jinjun, and Chen Lei
- Subjects
RADIOLARIA ,TETHYS (Paleogeography) ,PALEONTOLOGY ,SEDIMENTS ,EOCENE stratigraphic geology - Abstract
Quantitative analysis of Early Eocene radiolarian assemblages discovered in the sedimentary mélange (accretionary prism) of the Saga area, southern Tibet provides new information to constrain the timing of Tethys closure and the initial collision of India and Eurasia. The radiolarian species of Saga include Amphisphaera coronata (Ehrenberg), Buryella hannae Bak & Barwicz-Piskorz, Buryella clinata Foreman, Buryella tetradica Foreman, Calocycloma ampulla (Ehrenberg), Lamptonium fabaeforme constrictum Riedel and Sanfilippo, Lamptonium pennatum Foreman, Lithomespilus coronatus Squinabol and Lamptonium (?) colymbus Foreman. The adequate and reliable correlation of these radiolarians specimens indicates that the assemblage is of Early Eocene in age. The age and depositional environment of these radiolarians testify that deep ocean basins existed between India Plate and Asia Plate during the Early Eocene. The complete closure of Tethys must have taken place at least after the Early Eocene. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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16. SHRIMP dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River, northwestern Tibet.
- Author
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Shi RenDeng
- Subjects
OPHIOLITES ,JURASSIC stratigraphic geology ,JURASSIC paleoecology ,ZIRCON ,GEOCHRONOMETRY - Abstract
The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
17. Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite, Gerze, Tibet, China.
- Author
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YuXiu Zhang, KaiJun Zhang, Bing Li, Yang Wang, QingGuo Wei, and XianChun Tang
- Subjects
GEOLOGICAL time scales ,PETROGENESIS ,PETROLOGY ,OPHIOLITES - Abstract
Field relationship, along with petrographical, petrological, and geochemical characteristics, and zircon populations, indicates that the plagiogranites from the Lagkor Lake ophiolite in the Bangong-Nujiang suture zone (̃ 20 km south of Gerze County, central Tibet, China), derived from anatexls of hydrated gabbros by ductile shearing during transport of the oceanic crust. Therefore, this kind of plagiogranite is coeval to or little later than the spreading of the oceanic crust. Zircon SHRIMP age of 166 ± 2.5 Ma for the plagiogranites indicates that an oceanic basin existed in the western part of the Bangong-Nujiang zone In the Middle Jurassic. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
18. Microparticle record in the Guliya ice core and its comparison with polar records since the last interglacial.
- Author
-
Wu Guangjian, Yao Tandong, Thompson, L. G., and Li Zhongqin
- Subjects
GLACIERS ,ICE ,PARTICLES (Nuclear physics) ,NUCLEAR physics - Abstract
Based on the study of oxygen isotope and microparticle in the Guliya ice core, atmospheric dust and environmental changes in the northwest Tibetan Plateau since the last interglacial were revealed. The microparticle record indicates that low dust load on the Plateau in the interglacial. Particle concentration increased rapidly when the climate turned into the last glacial and reached the maximum during the MIS 4. In the Last Glacial Maximum, however, the enhancement of microparticle concentration was slight, differing to those in the Antarctic and Greenland. On the orbital timescale, both the temperature on the Tibetan Plateau and summer solar insolation in the Northern Hemisphere had their impact on the microparticle record, but the difference in phase and amplitude also existed. Though having the same dust source, microparticle records in the ice cores on the Tibetan Plateau and the Greenland seem to have different significance. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
19. The western boundary of extrusion blocks in the southeastern Tibetan Plateau.
- Author
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Ji Jianqing, Sang Haiqing, and Zhang Liansheng
- Subjects
PLATEAUS ,GEOLOGIC faults - Abstract
Focuses on a study that analyzed the western boundary of extrusion blocks in the dextral slide-slip faults in the southeastern Tibetan Plateau. Geometry and kinematics of dextral strike-slip faults; Methodology of the study; Results and discussion; Conclusions.
- Published
- 2000
- Full Text
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20. Changes in South Asian monsoon: New high-resolution paleoclimatic records from Tibet, China.
- Author
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Lingyu, Tang, Caiming, Shen, Kambiu, Liu, and Overpeck, J.T.
- Subjects
MONSOONS ,FOSSIL pollen - Abstract
Presents information on a study which determined the changes and evolution of the South Asian monsoon since the Last Glacial Maximum (LGM) using high-resolution fossil pollen records from small lakes in Tibetan Plateau, China. Modern pollen data set and transfer function; Reconstruction of temperature and precipitation since LGM; Discussion.
- Published
- 2000
- Full Text
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21. Comprehensive geophysical profile and lithosphere structures and geodynamics in...
- Author
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Xiangru, Kong and Qianshen, Wang
- Subjects
GEOPHYSICS ,GEODYNAMICS - Abstract
Focuses on a study on the comprehensive geophysical profile and lithosphere structures and geodynamics in the Qinghai-Xizang Tibetan plateau. Density and magnetism structure; Lithosphere velocity structure and conductivity structure of the plateau area; Summary.
- Published
- 1999
- Full Text
- View/download PDF
22. Water vapor image of snow storm process over southern Tibet.
- Author
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Fukang[1], Zhu, Xinjiang[2], Zheng, Jingbao[2], Luo, and Zengzhong[1], Li
- Subjects
WINTER storms ,WATER vapor transport - Abstract
Presents information on a study which focuses on the water vapor image of snow storm process over southern Tibet, China. Insights on the snow storm process over southern Tibet on the second ten-day of November 1995; Discussion on water vapor image; Obstruct effect of the Tibetan Plateau.
- Published
- 1999
- Full Text
- View/download PDF
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