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Journal of China university of geosciences 2003年第4期14卷 314-320页

作者： Sun Dongying Xia Wenchen faculty of earth {2., China {3. of geosciences, wuhan 430074 faculty of earth {2. China University of Geosciences Wuhan 430074

On the basis of establishment of radiolarian biostratigraphy and conodont biostratigraphy, a radiolarian Albaillella fauna in the transitional environment from Guadalupian to Lopingian Series in Permian was found at a pelagic chert section in southeast Guangxi, South China. Radiolarian Albaillella is one of the most sensitive biology to the transitional environment. The Albaillella fauna shows an ecological evolutionary process from Guadalupian to Lopingian: declined stage-recovery stage-flourishing stage. The study of characteristics of the Albaillella fauna in the transitional environment may provide more information, not only for the subdivision and correlation of a high-resolution biostratigraphy, but also for influence of radiolarian Albaillella fauna on the pre-Lopingian mass extinction.

关键词： Permian Guadalupian-Lopingian Series transitional environment radiolarian Albaillella fauna.

Sequence of Ductile Shear Zones in UHP Metamorphic Province with in Dabie Massif,China

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Journal of earth Science 1998年第3期17卷 3-9页

作者： Suo Shutian Zhong Zengqiu faculty of earth {2., China {3. of geosciences, wuhan 430074

Structural studies in the Dabie massif show that distribution of strain is extremely heterogeneous and illustrates the pattern of deformation partitioning in the ultra high pressure (UHP) metamorphic province on all scales. Based on the field structural analysis along with microstructural observation, at least five widespread episodes of ductile shear zone systems are identified by using geometric, kinematic and rheological indicators and they constitute a shear zone sequence in the UHP metamorphic province within the Dabie massif (DM), China. Each shear zone system, for example, the UHP eclogite facies shear zone system in the sequence, exhibits its own features including geometric styles, mineral assemblages, metamorphic pt conditions and deformation regimes during the formation of such shear zone system. Detailed macro and micro scopical features of different episodes of the shear zones are given with respect to mechanism of strain localization and deformation partitioning. The tectonic significance during the creation and exhumation of the UHP metamorphic rocks is evaluated briefly, as well. It is argued that the ductile shear zones in the UHP metamorphic province play an important role in the Dabie mountain building geodynamic process.

关键词： ductile shear zone UHP metamorphic province exhumation deformation partitioning Dabie massif.

Sorption of Eu^(3.) onto nano-size silica-water interfaces

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Science China earth sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1,2. YIN Xiulan3., ZHAO Linghu1 & LI Dien4 1. Department of earth {2., China {2. of {3., wuhan 430074, China 2. Northeastern Illinois {2., Chicago, IL 6062., USA 3. China Institute of Geo-Environmental Monitoring, Beijing 100081, China 4. Division of Chemistry, Los Alamos National Laboratory, Los Alamos, NM 87544, USA 1. Department of earth sciences China University of Geosciences 430074 Wuhan China 2. Northeastern Illinois university 60625 Chicago IL USA 3. China Institute of Geo-Environmental Monitoring 100081 Beijing China 4. Division of Chemistry Los Alamos National Laboratory 87544 Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1―8.5 and the initial Eu concentrations (CEu) of 2.× 10?5, 2.× 10?4 and 2.× 10?3.M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2.× 10?5, 2.× 10?4 and 2.× 10?3.M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75, ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.58 × 10?8, 1.58 × 10?7 and 1.58 × 10?6 mol/m2. The sorbed Eu species at pH 3., which is sorbed onto silica-water interfaces as an outer-sphere complex at pH 2. to ~6 at pH = 6. At pH = 6 – 8, Eu(OH)2., Eu(CO3.+ and Eu(CO3.2. form in the solutions, and Eu(CO3.+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3. species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals

Zircon geochronology and geochemistry of mafic xenoliths from Liaoning kimberlites:Track the early evolution of the lower crust,North China Craton

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Science China earth sciences 2004年第11期47卷 961-972页

作者： ZHENG Jianping1,YU Chunmei1,LU Fengxiang1 & LI Huimin2.1.faculty of earth {2.,China {3. of geosciences,wuhan 430074,China 2.Tianjin Institute of Geology and Mineral Resources,Tianjin 3.0170,China 1. faculty of earth {2. China University of Geosciences 430074 Wuhan China 2. Tianjin Institute of Geology and Mineral Resources 300170 Tianjin China

Mafic xenoliths from Paleozoic Fuxian kimberlites (Liaoning Province) mainly in- clude garnet granulite, with minor pyroxene amphibolite, meta-gabbro and pyroxene syenite. The SiO2.contents of the xenoliths are from 47.3.wt% to 49.9 wt%. The granulites are mainly coarse-medium grained and reasonably with well-developed granoblastic (mostly polygonal) texture, contain the assemblage of garnet + plagioclase + pyroxene + K-feldspar ±phlogopite. The mineral assemblage of the amphibolites is plagioclase + pyroxene + amphibole ±K-feldspar, with the equilibrium temperature and pressure conditions of 744—82.℃ and 0.76—0.88 GPa. The granulites are regarded as derivation from the lower crust depth (more than 2. km), below the amphibolites. Garnet granulites compositionally correspond to sub-alkalic basalt, and have wide ranges of Ni abundance (13.—840 ppm), and Nb/Y (0.12.1.85), Nb/U (3.51—53.86) and Ta/U (0.3.—2.48). The amphibolite and the syenite correspond to alkalic basalt. The Fuxian ma- fic xenoliths are regarded as the metamorphic product of the underplated magmas (including fractional crystallization or not) experienced the contamination with the pre-existed crustal com- ponents, and partly effected by kimberlitic magmas. The concordant ages of zircons for the gab- bro (2.10—2.80 Ma) and the near-concordant upper intercept ages of zircons for the garnet granulite and pyroxene amphibolite (2.78—2.3. Ma) indicate that they are currently known as the oldest deep-seated xenoliths from the lower crust of the North China Craton. These ages recorded the formation of the united Eastern Block of the North China Craton, That is, Neoar- chean (2.6—2.5 Ga) is an important continental crustal growth period of the North China Craton. The lower intercept age of the garnet granulite (1853.Ma) recorded an important tectonic thermal event in Paleoproterozoic. This event was probably related to collision of the East and West block, and resulted in the final assembly of the North China

关键词： mafic xenolith, petrochemistry, zircon geochronology, petrogenesis, lower crustal evolution, North China Craton.

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 sciences 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. China 2. Department of earth {2., Nanjing university, Nanjing 2.0093. China 3. Modern Analysis Center, Nanjing university, Nanjing 2.0093. China 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.

Multi-Layered Low-Angle Ductile Detachment System in Dabie-Sulu UHPM and HPM Belts, China

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Journal of earth Science 1999年第3期18卷 187-193页

作者： Suo Shutian Zhong Zengqiu(faculty of earth {2., China {3. of geosciences, wuhan 430074) faculty of earth {2. China University of Geosciences Wuhan 430074

The present-day observed crustal-scale tectonic style of ultrahigh-pressure metamorphic (UH-PM) and high-pressure metamorphic (HPM ) belts in the Dabie-Sulu region was dominantly formedby extensional processes, postdating the Triassic collision between the Sino-Korean and Yangtze cratons. The extensional structures overprinting the previous structures related to contraction that produced the thickened continental crust of the UHPM and HPM belts, in particular display the typical features of a Cordilleran-type metamorphic core complex, in which at least four regionalscale, low-angle ductile shear zones that constitute a detachment system, are recognized in the Dabie region. In the Sulu region, the extensionaI structures show in the form of small-scale domes or a regional-scale SE-dipping pseudo-monocline. The geometry and the kinematics of tbe detachment zones are briefly described and their significance for the exhumation of UHPM and HPM rocks is discussed. It is iniliated that the subhorizontal crustal-scale extensional flow in the middle-lower crust, under amphibolite- to greenschist-facies conditions, was an important tectonothermal process at 2.0- 170 Ma and the exhumation or the UHPM and HPM rocks was achieved at least in part along multi-layered detachment zones. The regional detachment system has been the main factor enabling UHPM and HPM rocks to be brought from middle-lower crustal levels to middle-upper crustal levels.

关键词： detachment system UHPM and HPM rocks exhumation ductile shear zone,Dabie massif Dabie-Sulu region

Depositional Model and Tectonic Evolution of Tertiary Transform-Extensional Basins in Northeast China: Case Study on Yitong and Damintun Grabens

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Journal of earth Science 1997年第1期16卷 62-67页

作者：  Xie Xinong Huang Yanqiu faculty of earth Resources, China {2. of {3., wuhan 430074Lu Zongshengfaculty of earth sciences, China {2. of {3., wuhan 430074

? The formation and evolution of the Tertiary transformextensional basins in Northeast China are controlled by extensional and strikeslidding combinational processes because the giant strikeslip fault system, TanchengLujiang fault, cut through the basement or margin. Two kinds of structural styles have been identified in Northeast China: Yitong and Damintun styles. The former shows a clear asymmetry, in which sediments came mainly from two lateral sides and thick filling sediments were adjacent to the main strikeslip fault. The latter shows symmetry filling, in which sediments came from the long axial ends in addition to from two lateral sides. The tectonic evolution of Tertiary transformextensional basins in Northeast China underwent three stages: Eocene extensional, Oligocene transformextensional and Neogene transpressional stages.

关键词： transformextensional basin Tertiary Yitong graben Xialiaohe basin.

Mass and Energy Transportation in Ore-Forming Processes of Sulfide Deposits in Tongling District

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Journal of earth Science 1999年第4期18卷 299-304页

作者： Cen Kuang Yu Chongwen(faculty of earth {2., China {3. of geosciences, wuhan 430074) faculty of earth {2. China University of GeosciencesWuhan 430074

Based on dynamics of heat conduction, fluid flow caused by heating and chemical material transport induced by fluid flow, temperature and stream fields of fluid flow in ore-forming processes of Cu-Au sulfide in the Tongling district deposits was modeled and analyzed. It is shown that: (1) Mass and energy flow caused by fluid flow is key problem of kythrothermal ore-forming processes; the heating from magma intruded is basic power for driving fluid flow. (2. occurrence of pluton, different chemical property and porosity of wall rocks and infiltration restrict the specifically field of precipitation for ore-forming ***, the dissolution and precipitation field for ore-forming material in deposit can be forecasted. (3. Iron and sulfur material comes mostly from sandstone formation of Wutong Group, which contains pyrite and high porosity. The cataclastic dolomite interlayered in sandstone and limestone is a favorable place for ore accumulating. The difference of chemical property between sandstone and dolomite forms a favorable interface for ore-forming processes.

关键词： heat conduction mass transportation fluid path-line streamline

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\+3.. Department of earth {2., Nanjing {2., Nanjing 2.0093. China 2. Center of Material Analysis, Nanjing {2., Nanjing 2.0093. China 3. Xi’an Laboratory of Loess and Qu Department of earth sciences 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.

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

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Science China earth sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1, CAI Keqin2.& YU Shengsong3.1. Nanjing Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, China 2. China {2. of {2., Beijing 100083. China 3. Institute of Salt Lakes, Chinese Academy of sciences, Xining 810008, China 1. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences 210008 Nanjing China 2. China university of geosciences 100083 Beijing China 3. Institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in China for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.