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Chinese Science Bulletin 1998年第23期43卷 1950-1955页

作者： WANG Xiangyun 1, WANG Chao 2. GUO Huadong 2.and SHI Yangshen 1 1. department of earth {2., nanjing University, nanjing 2.0093, china 2. Institute of Remote Sensing Applications, Chinese Academy of {2., Beijing 100101, china department of earth {2. Nanjing University Nanjing 210093 China Inst. of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

ERS 1 WSC data were obtained by international cooperation. The distributive characteristics of radar backscattering coefficient image of china land surface are analyzed and the research results are presented. The capability of ERS 1 WSC data for monitoring land surfaces is investigated. The results show that the radar backscattering coefficient images can reveal the natural landform features of china land. Using the WSC data can discriminate six types of major land coverage, including evergreen vegetation and snow covered region, vegetation and crops, mountains, grassland, desert and grassland, desert. On the whole, the radar backscattering coefficient image of china land is the synthesis of the vegetation map and terrain map. Statistical study of the typical terrain shows that the radar backscatter coefficients of china land range from -2. dB to -5 dB. The lowest value corresponds to the deserts of Badain Jaran, Takla Makan, and Tengger. The highest value corresponds to snow covered regions of Himalaya Mountains and Tianshan Mountains.

关键词： ERS 1 WSC radar backscattering coefficient land surfaces coverage.

Low temperature albitization in Caino-Mesozoic reservoir sandstones from North Tarim, and a discussion on the fluid origin

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Chinese Science Bulletin 1999年第S2期44卷 35-37页

作者： YE Ying~1, HU Shouxi~2.and SUN Jinggui~2.1. department of earth {2., Zhejiang University, Hangzhou 31002., china 2. department of earth sciences, nanjing University, nanjing 2.0008, china department of earth {2. Zhejiang University Hangzhou 310027 China department of earth {2. Nanjing University Nanjing 210008 China

CAJNOZOIC and Mesozoic in North Tarim are predominantly a set of terrestrial detrital formations. In thereservoir sandstones in the area, albite is one of the widely developed authigenic mineral. Micro-structural evidence shows that diagenetic albite occurs as euhedral crystals in the pore, and replaces feldsparand other detritus along cleavage and micro-crack. EPMA analyzing found that some of the alteration product has a chemical composition between purealbite and the replaced detrital feldspar. For example, composition of replaced alkali feldspar is betweenmicrocline and albite, and content of altered plagioclase decreases continuously. This has been regardedas direct evidence for fluid replacement, for feldspar crystallized from solution or magma is usually withfixed chemical composition. Taking alkali feldspar as an example, although Kf and Ab forming completeisomorphous admixture in high temperature, they exsolved out as two relative pure phases while temperature decreases.

关键词： low temperature albitization sandstones fluid origin North Tarim.

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china earth {2. 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2. JIANG Shaoyong1,2. WANG Xiaolei1,2. YANG Jinghong 1,2.& ZHANG Mengqun 3 1. State Key Laboratory of Mineral Deposit Research, nanjing University, nanjing 2.0093,{2. 2. department of earth sciences, nanjing University, nanjing 2.0093,{2. 3. Modern Analysis Center, nanjing University, nanjing 2.0093,{2. 1. State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing 210093 China 2. department of earth sciences Nanjing University Nanjing 210093 China 3. Modern Analysis Center Nanjing University Nanjing 210093 China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2.contents in the range of 1.92.-3.2.%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.2., which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

EPR studies of Mn^(2.) in the Loess Plateau of central china: Implication for variation of the East Asia summer monsoon

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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2.and LU Huayu\+31. department of earth {2., nanjing University, nanjing 2.0093, china 2. Center of Material Analysis, nanjing University, nanjing 2.0093, china 3. Xi’an Laboratory of Loess and Qu department of earth {2. Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2. EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2. EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2.

Refinement of the crystal structure for a new mineral──antimonselite

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Chinese Science Bulletin 1998年第5期43卷 413-416页

作者： MIN Maozhong 1, ZHAI Jianping 1, WANG Xiangyun 1,SHEN Baopei 2. WEN Guangdou 2.and FAN Tao 2.. department of earth {2., nanjing University, nanjing 2.0093, china 2. Uranium Geology Bureau of Central-South china, Changsha 410000, china department of earth {2. Nanjing University Nanjing China Uranium Geology Bureau of Central-South china Changsha China

The crystal structure of a new mineral of the stibnite group, Sb-2.e-3, has been determined. The cell constants, obtained by least-squares calculation from direct θ -value’s measurements on the diffractometer are: a =1.158 8(5), b =1.174 4(4), c =0.395 5(2. nm; orthorhombic; V =0.538 2. nm+3; Z =4. The space group is Pbnm. X-ray single crystal data, using Mo K α radiation, were measured on a RIGAKU RASA-5RP automated diffractometer and refined to a final R index of 0.048 1. Sb-2.e-3 is isostructural with Sb-2.-3 and Bi-2.-3. Each Sb(1) atom is six-coordinated by 3 Se(1), 1 Se(2. and 2.Se(3) atoms at distances 0.2.6 0-0.32. 6 nm. Each Sb(2. atom is seven-coordinated by 2.Se(1), 2.Se(2. and 3 Se(3) atoms at distances of 0.2.8 1- 0.346 7 nm. The crystal structure consists of chains parallel to c or needle axis. The strongest bonds (shortest separations) are within the chains. Many important physical properties of antimonselite (optical, ferroelectric, etc.) are related to its crystal structure.

关键词： new mineral antimonselite crystal structure.

Experimental study on the interaction between peat,lignite and germanium-bearing solution at low temperature

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Science china earth {2. 2005年第9期48卷 1411-1417页

作者： QI Huawen1,2. HU Ruizhong1 & QI Liang1 1. Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of sciences, Guiyang 550002. china 2. {2. of earth Science, nanjing University, nanjing 2.0093, china 1. Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of earth Science Nanjing University 210093 Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 2.―100℃ and at pH 2.96―12.08. The results show that the apparent transfer ratios of peat and lignite for Ge in the solution were positively correlated with temperature in acid environment (initial pH=2.96), and the ratios (up to 86.5%) of lignite were obviously higher than those (up to 58.5%) of peat, but the organic transfer ratios of lignite were lower than those of peat. The activation energy values for interaction between peat, lignite and Ge-bearing solution are 30.96 and 15.67 kJmol?1, respectively. The strong acid (initial pH=2.96) and the strong alkaline (initial pH=12.08) environment contribute to the transfer of Ge in the solution. At 4

关键词： low temperature, peat, lignite, Ge4+, complexation.

Thermal-rheological structure of the lithosphere beneath Jiyang Depression:Its implications for geodynamics

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Science china earth {2. 2005年第10期48卷 1569-1584页

作者： LIU Shaowen1,2. WANG Liangshu2. GONG Yuling2. LI Cheng2. LI Hua2.& HAN Yongbing2.1. department of Urban and Resources, nanjing University,{2., china 2. department of earth sciences, nanjing University,{2., china department of Urban and Resources nanjing University nanjing china department of earth {2. nanjing University nanjing china

Jiyang Depression, located in the southeast Bohai Bay Basin, has the geomorpho-logic framework of multiple uplifts intervening with sags. Combined the abundant geo-temperature data and thermo-physical parameters of rock samples derived from oil and gas exploration during the past years, with geothermal approaches, here we investigate the litho-spheric thermal regime of this depression. Consequently, based on the obtained thermal struc-ture of the lithosphere, along with rheological modeling, the lithospheric rheological profiles of Jiyang Depression are then determined. Our results show that the temperature at the bottom of sedimentary cover within depression varies from 12.℃ to 2.8 ℃ , accompanied with the base-ment heat flow ranging between 54.3 and 60.5 mW/m2. and 406℃-436℃ for temperature at the bottom of the upper crust, along with heat flow varying from 47.7 to 52.6 mW/m2. while the tem-perature at the bottom of the middle crust is between 537 ℃ and 572.℃, as well as heat flow ranging from 41.3 to 56.3 mW/m2. The temperature at Moho ranges from 669 ℃ to 72. ℃, the heat flow derived from mantle is between 38.1 and 43.1 mW/m2. and calculated thickness of the thermal lithosphere beneath depression varies from 71 to 90 km. Lithospheric thermal regime is a close correlation with such factors as crustal thickness and surface heat flow, etc. Usually, the larger the surface heat flow, the larger the deep temperature and heat flow within lithosphere, and the thinner the thermal lithospheric thickness. This high thermal regime of the lithosphere in Jiyang Depression is thought to be related to Cenozoic back-arc spreading during the western Pacific plate subduction into Eurasian continent. Lithospheric rheological modeling shows that the lithosphere in Jiyang Depression is characterized by its distinct rheological stratification as follows: The upper and most part of the middle crust are of brittle, while the lower crust and the lower part of middle crust are all ductile

关键词： Jiyang Depression, geothermics, rheology, effective elastic thickness, geodynamics.

Variation of the Fe/Mn ratio of ferromanganese crusts from the Central North Pacific: implication for paleoclimate changes

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Progress in Natural Science:Materials International 2005年第6期15卷 530-537页

作者： LU Zunli1**, LING Hongfei1*, ZHOU Feng1, JIANG Shaoyong1, CHEN Xiaoming1 and ZHOU Huaiyang2.1. State Key Laboratory for Mineral Deposits Research, department of earth {2., nanjing University, nanjing 2.0093, china 2. Guangzhou Institute of Geochemistry, Chinese Academy of {2., Guangzhou 510640, china)department of earth & Environmental Science, University of Rochester State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China department of earth & Environmental Science University of Rochester Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing Fe/Mn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of Fe/Mn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high Fe/Mn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3 Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of Fe/Mn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The Fe/Mn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, Fe/Mn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.

关键词： Fe/Mn ratio ferromanganese crust central North Pacific paleoclimate.

Lithology, kinematics and geochronology related to Late Mesozoic basin-mountain evolution in the Nanxiong-Zhuguang area, South china

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Science china earth {2. 2004年第8期47卷 673-688页

作者： SHU Liangshu1, DENG Ping1,2. WANG Bin1, TAN Zhengzhong2. YU Xinqi1 & SUN Yan1 1. department of earth {2., nanjing University, nanjing 2.0093, china 2. Research Institute No.2.0, CNNC, Shaoguan 512.2., china 1. department of earth {2. Nanjing University 210093 Nanjing China 2. Research Institute No.2.0 CNNC 512026 Shaoguan China

The Nanxiong red-bed basin and its adjacent Zhuguang granite form a distinctive basin-mountain landform in the Nanling region, South china. Research results suggest that the Zhuguang granite is a polyphase composite pluton developed on the metamorphic basement of the paleo-Tethys-paleo-Asian tectonic regime and possesses geometrical and kinematic features of hot-doming extensional tectonics at the middle-upper crustal level, which is considered as a magmatic complex that resulted from the collision-orogeny during the Indosinian Period, the subduction-consuming during the Early Yanshanian Period and the intra-continental basaltic underplating and deep-seated geodynamics during the Late Yanshanian Period. The Nanxiong basin is a Late Cretaceous-Paleogene asymmetric faulted basin that is characterized by a fault boundary on the northern side and an uncomformable boundary on the southern side, its deposit center was migrated gradually from south to north. Structural kinematic results on the basin-mountain coupled zone demonstrate that the ductile and the brittle rheological layers show a quite coincident sense of shear, implying that it is a continuous process from the ductile extensional deformation followed by locally sinistral strike-slip shear at a middle-crustal level to the brittle tensional deformation at a upper-crustal level during formation of granitic doming extensional tectonics. The Zhuguang granite and the Nanxiong faulted basin constructed a semi-graben tectonic system. Lithological and geochemical results suggest that the Late Triassic to Jurassic granitic bodies in the Zhuguang have some similar features: high SiO2. Al2.3, K2. contents, alkalinity index > 2.8, ANKC value > 1.1, LREE-enriched pattern with high REE contents, marked negative Eu anomalies, enrichment in Rb and Th, depletion in Ba and Nb, showing a K-rich and Al-rich calc-alkaline affinity, which suggest a continuous magmatic evolution from Late Triassic to Jurassic. Formation of Nanxiong ba

关键词： lithology,structural kinematics,basin-mountain evolution,SHRIMP age,Zhuguang granite,Nanxiong basin.

Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china earth {2. 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. department of Geography, nanjing Institute of Meteorology, nanjing 2.0044, china 2. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China Chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China Chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 512.hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.