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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science china Earth Sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1. JIN Zhenmin2.& ma Jin1.1. State Key Laboratory of {1. Dynamics, Institute of Geology,{1.,{2., china 2. Faculty of Earth Sciences, china University of Geosciences, Wuhan 430074, china State Key Laboratory of earthquake Dynamics Institute of Geology China Earthquake Administration Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 2..67 ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 1..82.to 1..37 ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.2. ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

Deep tectonic setting of the 2.08 Wenchuan M_s8.0 earthquake in southwestern{1.―Joint analysis of teleseismic P-wave receiver functions and Bouguer gravity ano{2.lies

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Science china Earth Sciences 2009年第2期52卷 166-179页

作者： LOU Hai1. WANG ChunYong1. L ZhiYong2. YAO ZhiXiang1. DAI ShiGui2.& YOU HuiChuan1.1.Institute of Geophysics, china earthquake administration, {1. 1.0081.{2. 2.earthquake administration of Sichuan Province, Chengdu 61.041.{2. Institute of Geophysics China Earthquake Administration Beijing China earthquake {1. of Sichuan Province Chengdu China

Teleseismic P-wave receiver functions at 2. broadband seismic stations in the Longmenshan fault zone (LMFZ) and its vicinity were extracted, and the crustal thickness and the P- and S-wave velocity ratio were calculated by use of the H-k stacking algorithm. With the results as constraints, the S-wave ve-locity structures beneath each station were determined by the inversion of receiver functions. The crustal structure of the Rear-range zone is similar to that of the Songpan-Garze Block, whereas the velocity structure of the Fore-range zone resembles that of Sichuan Basin, implying that the Central Principal Fault of LMFZ is the boundary between the eastern Tibetan Plateau and the Yangtze Block. Lower velocity zone exists in lower crust of the Songpan-Garze Block and the central-southern seg-ment of the Rear-range zone, which facilitates the detachment of the material in upper and middle crust. Joint analysis of the receiver functions and the Bouguer gravity anomalies supports the thesis on the detachment-thrust mode of the LMFZ. A double-detachment pattern is suggested to the tectonic setting in the Songpan-Garze Block. The upper detachment occurs at the depth of {2.-{2. km, and represents a high-temperature ductile shear zone. There is a lower detachment at the depth of about 30 km, below which the lower crust flow exists in the eastern Tibetan Plateau. Interpretation of the Bouguer gravity anomalies indicates that the Sichuan Basin is of higher density in upper and middle crust in compari-son with that of the Songpan-Garze Block. The LMFZ with higher density is the result from the thrusting of the Songpan-Garze Block over the Sichuan Basin. In the lower crust, higher P velocity and higher density in the Sichuan Basin are related to more rigid material, while lower S velocity and lower density in the Songpan-Garze Block are related to the softened and weakened material. The higher density block beneath the Sichuan Basin obstructs the eastward flow of lower crustal ma

关键词： Longmenshan fault zone (LMFZ) Wenchuan Ms8.0 earthquake deep tectonic setting teleseismic receiver function

Source mechanism of strong aftershocks (M_s≥5.6) of the 2.08/05/1. Wenchuan earthquake and the implication for seismotectonics

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Science china Earth Sciences 2009年第6期52卷 739-753页

作者： ZHENG Yong1.2.ma HongSheng3,Lü Jian4,NI SiDao5,LI YingChun6 & WEI ShengJi2.1.Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,{1. 2.Institute of Geophysics,Chinese {1. {2.,beijing 1.0086,{1. 3 Institute of {1. Science,Chinese {1. {2.,beijing 1.0086,{1. 4 {1. {2. of Jiangxi Province,Nanchang 330039,{1. 5 School of Earth and Space Science,University of Science and Technology of{1.},Hefei 2.002.,{1. 6 {1. {2. of Jiangsu Province,Nanjing 2.0}01.,{1. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Institute of Geophysics Chinese Earthquake Administration Beijing China Institute of earthquake Science Chinese Earthquake Administration Beijing China earthquake {1. of Jiangxi Province Nanchang China School of Earth and Space Science University of Science and Technology of China Hefei China earthquake {1. of Jiangsu Province Nanjing China

Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2.08/05/1. Wenchuan earthquake, which were well recorded by per{1.nent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of{1., and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are {1.inly thrust earthquakes, which is consistent with initial mechanism of the {1.in shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the {1.in shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~1. km). So we suspected that in the north part the {1.in shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.

关键词： focal mechanism seismotectonics Wenchuan earthquake cut and paste.

Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science china Earth Sciences 2010年第4期53卷 575-590页

作者： LI MingXing1.2.ma ZhuGuo1.& DU JiWen3 1.Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing {1.,{2. 2.Graduate University of Chinese Academy of Sciences,beijing 1.0049,{2. 3 Shaanxi administration of Meteorology,Xi’an 71.01.,{2. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China Shaanxi administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1.51.to 2.04,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

Distribution characteristics of seamount cobalt-rich ferromanganese crusts and the determination of the size of areas for exploration and exploitation

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Acta Oceanologica Sinica 2011年第3期30卷 63-75页

作者： HE Gaowen ma Weilin SONG Chengbing YANG Shengxiong ZHU Benduo YAO Huiqiang JIANG Xunxiong CHENG Yongshou Guangzhou marine Geological Survey Guangzhou 510075 China Second Institute of Oceanography State Ocean Administration Hangzhou 310012 China china Ocean Mineral Resources R ＆ D Association Beijing 100860 China beijing General Research Institute of Mining ＆ Metallurgy Beijing 100070 China National marine Information Center Tianjin 300171 China

In 2.01. the International Seabed Authority （ISBA） initiated the consideration relating to the Regulations for Prospecting and Exploration for Hydrothermal Polymetallic Sulphides and Cobalt-rich Ferromanganese Crusts in the Area at its 7th session. Since then, the consideration of the Regulations has been mainly focused on the size of areas to be allocated for exploration and exploitation of the crusts. This paper, based on the investigation data and the analysis of the distribution characteristics of the crusts, suggests a model for determining the size of areas for exploration and exploitation of the crusts, taking into account various factors such as production scale, crust thickness and grade, mineable area proportion, recovery efficiency, exploration venture, and so on. Through the modeling, the paper suggests that the exploration area （the area covered by each application for approval of a plan of work for exploration of cobalt-rich crusts） shall be 4 856 km2.and the exploitation area （the mine site area） shall be 1.2.0} km2. for 2. years of 1.million wet tonnes annual production.

关键词： cobalt-rich ferromanganese crusts exploration and exploitation area seamounts regulation on exploration

Permeation-enhancing effects of chitosan formulations on recombinant hirudin-2.by nasal delivery in vitro and in vivo

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Acta Pharmacologica Sinica 2005年第11期26卷 1402-1408页

作者： Yu-jie ZHANG~(1.2., Chang-hua ma,Wan-liang LU, Xuan ZHANG, Xiao-liang WANG, Jian-ning SUN, Qiang ZHANG~(1.3) ~1.School of Pharmaceutical Sciences, Peking University Health Science Center, beijing 1.0083,{1.,~2.Department of Chinese Pharmacy, beijing University of Traditional Chinese Medicine, beijing 1.01.2.{1. School of Pharmaceutical Sciences Peking University Health Science Center Beijing China Department of Chinese Pharmacy Beijing University of Traditional Chinese Medicine Beijing China

Aim: To investigate the enhancing effects of chitosan with or without enhancers on nasal recombinant hirudin-2.(rHV2. delivery in vitro and in vivo, and to evaluate the ciliotoxicity of these formulations. Methods: The permeation-enhancing effect of various chitosan formulations was estimated by using the permeation coefficient of fluorescein isothiocyanate recombinant hirudin-2.(FITC-rHV2. across the excited rabbit nasal epithelium in vitro. The effect was further evaluated by measuring the blood concentration level after nasal absorption of FITC-rHV2.in rats. The mucosal ciliotoxicity of different formulations was evaluated with an in situ toad palate model. Results: Chitosan at a concentration of 0.5% with or without various enhancers significantly increased the permeability coefficient (P) and relative bioavailability (Fr) of FITC-rHV2.compared with the blank control. The addition of 1.% sodium dodecylsulfate, 5% Brij35,5% Tween 80,1.5% menthol, 1. glycyrrhizic acid monoammonium salt (GAM) or 4% Azone into the 0.5% chitosan solution resulted in a further increase in absorption (P1. of chitosan with 5% hydroxyl-propyl-beta-cyclodextrin (HP-β-CD), 5% lecithin or 0.1.% ethylenediamine tetraacetic acid (EDTA) was not more effective than using the 0.5% chitosan solution alone. Chitosan alone and with 5% HP-β-CD, 0.1.% EDTA, 1.% GAM or 5%Tween80 was relatively less ciliotoxic. Conclusion: Chitosan with or without some enhancers was able to effectively promote the nasal absorption of recombinant hirudin, while not resulting in severe mucosal ciliotoxicity. A chitosan formulation system would be a useful approach for the nasal delivery of recombinant hirudin.

关键词： nasal absorption hirudin chitosan formulation permeability bioavailability enhancer: ciliotoxicity

^(2.4)Th/^(2.8)U disequilibrium and particulate organic carbon export in the northwestern South china Sea

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Acta Oceanologica Sinica 2011年第3期30卷 55-62页

作者： ma Hao ZENG Zhi YU Wen HE Jianhua CHEN Liqi CHENG Jianping YIN Mingduan ZENG Shi Department of Engineering Physics Tsinghua University Beijing 100084 China Key Laboratory of Global Change and marine-Atmospheric Chemistry State Oceanic Administration Xiamen 361005 China Key Laboratory of Particle ＆ Radiation Imaging （Tsinghua University） Ministry of Education Beijing 100084 China Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense Beijing 100084 China

2.4Th was utilized as a tracer of particulate organic carbon （POC） export in the northwestern South china Sea （SCS） on the basis of the data collected at four stations during a spring cruise. Depth profiles of dissolved and particulate 2.4Th activities were measured in the upper 60m, showing a significant deficit relative to 2.Su over the investigated stations. A stratified structure of 2.4Th-2.su disequilibrium was in general observed in the upper 60 m water column, indicating that the euphotic zone of the northwestern SCS in this reason can be divided into two layers, an upper and lower layer, with different export rates. POC export fluxes were esti{1.ted from a one-dimensional steady state model of 2.4Th fluxes in combination with the measurement of POC/2.4Th ratios on suspended particles. The POC export in this region ranged from 8.2.to 2..0 mmol/（m2.d）, with an average of 1..0 mmol/（m2.d）, and was slightly higher than those previously reported in the southern SCS.

关键词： 2.4Th 2.su disequilibrium POC export South china Sea

THE GLOBAL TECTONIC SYSTEMS AND A LATITUDINAL MOUNTAIN-PLATEAU CHAIN ON THE NORTH HEMISPHERE

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地学前缘 2000年第S1期7卷 344-345页

作者： ma {1.(Institute of Geology,{2. Seismological Bureau,{2. 10002.,{2.)

Three global tectonic systems that formed since the middle Jurassic (1.0ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by ma zongjin et al.(1.96).They are the circum\|Pacific tectonic system,the mid\|ocean ridge tectonic system and the intra\|continental tectonic system of the north *** map shows that about 80% of the total length of the continental orogens are concentrate on the north hemisphere of the earth,of which a latitudinal mountain\|plateau chain occur within a zone between north latitude 2.°and 50°.Seismic and volcanic activities demonstrate that the intracontinental tectonic system on the north hemisphere is still *** distribution of the continental deep\|focus {1.s and almost ultra high\|pressure rock found so far over the World,that are assumed both related to recent or previous deep subduction of continent,along with this *** latitudinal mountain\|plateau chain is subdivided into four active tectonic region of Qinghai—Xizang(Tibet),Iranian,eastern mediterranean and North American,both characterized by an individual similar mountain\|plateau\|basin structure with major active boundaries or controlling faults (Fig.1..These active regions are all close to primary dynamic boundaries of continent\|continent *** of source mechanisms shows that regional tectonic stress field in these regions are dominated by a nearly NS or NNE—SSW direction compression corresponding to a local plate motions and a global compressive *** between the formation of the continental latitudinal mountain\|plateau chain on north hemisphere and the oceanic plate tectonics is discussed using the information of the “map of magnetic Lineations of the World’s Ocean Basins (Cande et al.,1.89)”and the Cenozoic and Mesozoic tectonic evolution in the *** 49 accretion units formed during 6 accretion stages of the ocean spreading in three chief oceans (the Pacific,the India and th

关键词： global asymmetrical system geodynamics mountain\| plateau chain seismotectonic system latitudinal tectonic zone

Nd isotope as the tracer of seawater evolution of early Miocene in the eastern Pacific Ocean

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Chinese Science Bulletin 2003年第B6期48卷 106-110页

作者： LIU Jihua~(1.2.3), CHEN Lirong~1. WANG Yingxi~4 & HAN Jianxiu~5 1. Institute of Oceanology, Chinese Acadcmy of ences, Qingdao 2.6071. china 2. Key Lab of {1.rine Sedimentology and Environmental Geology, First Institute of Oceanograpgy, State Oceanic {1., Qingdao 2.6061. china 3. Graduate School, Chinese Academy of Sciences, beijing 1.0039. china 4. Modern Analysis Center, Nanjing University. Nanjing 2.0}093. china 5. Guangzhou {1.rine Investigation Bureau, Guangzhou 51.760. china Institute of Oceanology Chinese Academy of Sciences Qingdao China Key Lab of marine Sedimentology and Environmental Geology First Institute of Oceanograpgy State Oceanic Administration Qingdao China Graduate School Chinese Academy of Sciences Beijing China Modern Analysis Center Nanjing University Nanjing China Guangzhou marine Investigation Bureau Guangzhou China

Fifty-six samples of nannofossil ooze were collected from Core PC5794 in the northern equatorial Pacific at 5 cm intervals. With the methods of mass spectrometer (VG354) and ICP, the Nd isotopic compositions (εNd(t)), Mn contents and Mg/Sr ratios of carbonate phase have been analyzed. CaCO3 contents of bulk sediments were obtained by dissolution of 0.5 mol/L HCl. Based on these data, the high-resolution εNd(t) profile of seawater in early Miocene with core depth(or time) have been established. The values of εNd(t) range from -6.2.to -2.97 and 4 fluctuation cycles existed during 2..06-2..02.ma. 4 low εNd(t) values (about -6.4) correspond to high CaCO3 contents, which implicates that there were 4 cold epochs or 4 times of Antarctic Bottom Water activity. They occurred at the time of 2..06 ma, 2..85 ma,2..88 ma and 2..2. ma, respectively. High εNd(t) values correspond to the high Mn contents and high values of Mg/Sr ratio, which indicates the existence of 4 intense hydrothermal activity periods during 2..06-2. ma, the durations of them are 4.05-2..98 ma, 2..69-2..1. ma, 2..74-2..37 ma and 2..06-2..02.ma, respectively.

关键词：同位素钕示踪原子海水演化中新世太平洋微化石分光计持续期海水样品