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Experimental remolding on the caprock's 3D strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science China earth sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2,WANG Qingfei1,WAN Li1,SUN Zhongshi3,YANG Liqiang1 & GAO Bangfei1 1. State Key Laboratory of Geological Processes and Mineral Resources,China university of Geosciences,Beijing 100083,China 2. Faculty of earth sciences,China university of Geosciences,Wuhan 4.0074.China 3. Department of earth sciences,jilin university,changchun 130061,China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of earth sciences China University of Geosciences Wuhan 430074 China Department of earth sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3D structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3D structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3D structure between the experimental model and the field phenomena, we verify the following 3D deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2) in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3) the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4. the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3D structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

^4.Ar/^39Ar dating of Daqingshan thrust

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Chinese Science Bulletin 2003年第24期48卷 2734-2738页

作者： LIU Zhenghong, XU Zhongyuan & YANG Zhensheng college of earth sciences, jilin university,{4., China Correspondence should be addressed to Liu Zhenghong (e-mail: liuzhenghong@***) college of earth sciences Jilin University Changchun 130061 China

The Daqingshan thrust system, to the south of the Shiguai Mesozoic basin, is a complex system of top-to- the-north thrusting tectonic sheets. The thrust system has a complicated evolution due to multi-stage thrusting. In order to date the thrusting events, syntectonic muscovite and bio-tite grains are respectively analyzed with normal 4.Ar/39Ar dating and laser 4.Ar/39Ar dating, which yield 2 isochron ages, i.e. 193.74.3.88 Ma and 121.6 1.6 Ma. These ages suggest that faults within the Daqingshan thrust system formed dur-ing 2 stages of thrusting, one the early Indosinian and the other the late Yanshanian. The isotopic dating is consistent with field geological relations. Indosinan deformation is evi-denced by top-to-the-north thrusting, with the occurrence of a series of large-scale east-west trending thrust faults and folds, while the Yanshanian thrusting is characterized by top-to-the-NNW thrusting. It is superposed on and modifies early Indosinian thrust faults.

关键词： Ar 氩中生代云母同位素

Discovery of eclogite and its geological significance in Qiangtang area, central Tibet

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Science Bulletin 2006年第9期51卷 1095-1100页

作者： LI Cai1, ZHAI Qingguo2, DONG Yongsheng1 & HUANG Xiaopeng11. college of earth sciences, jilin university,{4., China 2. Institute of Geology, Chinese Academy of Geological sciences, Bei- jing 100037, China college of earth sciences Jilin University Changchun 130061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 4.Ar/39Ar age of 220 Ma and a phengite 4.Ar/39Ar age of 221.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- Chinese epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.

关键词： Qianghai-Tibet Plateau Qiangtang eclogite tectonics.

The Discovery and Study of Mantle-Derived Dunite Inclusions in Hornblende-Diorite in the Handan-Xingtai Area,Hebei

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 259-269页

作者： Xu Wenliang Lin Jingqian changchun Universily of earth sciences, changchun,{4. Jiang Minxi changchun university of earth sciences Changchun Jilin

Phlogopiie-and diopside-bearing dunite occurs as rounded inclusions in hornblende-diorite. Thepetrofabrics, mineral composition and abundances of the trace elements in the dunite indicate that the inclu-sions were derived from the upper mantle and are the residues of high-degree partial melting of mantlepeirdotite. The study of trace elements in the inclusions and their host rocks shows that the magma was origi-nated from the mantle which was enriched in incompatible elements by mantle metasomatism prior to the par-tial melting.

关键词： The Discovery and Study of Mantle-Derived Dunite Inclusions in Hornblende-Diorite in the Handan-Xingtai Area Hebei

Low-Pressure Metamorphism of Granulite Facies in an Early Proterozoic Orogenic Event in Central Inner Mongolia

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 63-77页

作者： Liu Xishan, Jin Wei and Li Shuxun changchun university of earth sciences, changchun, jilin Sun Sheping changchun university of earth sciences Changchun Jilin

According to the kinds of feldspar and rock associations in the Ai-rich gneisses, the low-pressure metamorphic crust of the Early Proterozoic granulite facies in central Inner Mongolia can be divided into southern and northern belts which are composed of six rock associations. They represent the relevant rock sequences of the layered metamorphic rock series formed under specific metamorphic temperature and pressure conditions as well as tectonic environments. Mineral inclusions and reaction texture have recorded that the medium-temperature high-pressure mineral assemblages are replaced by the high-temperature low-pressure mineral assemblages, thus, giving rise to: garnet+quartz→ hypersthene+plagioclase; kyanite→sillimanite and garnet+kyanite/sillimanite+quartz→cordierite. The deformation fabrics of the rocks, the change of mineral assemblages and the PTt path of metamorphism indicate that the contempranceous high-temperature normal-slip ductile shearing is the main cause of the formation of the low-pressure metamorphic crust of granulite facies. In the orogenic event, the co-action of thrusting and extension resulted in the change of a medium-temperature high-pressure metamorphic environment into the high-temperature low-pressure metamorphic conditions.

关键词： Early Proterozoic change of mineral assemblages thrusting extension orogenic event.

SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science China earth sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2 & SU Li3 1 Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, China 2 college of earth sciences, jilin university, changchun 130061, China 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources, China{4. of Geo- sciences, Beijing 100083, China 1. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 4.7±4.Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

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Science China(Life sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3, WANG Zhenwei3, SHAN Xiaohui2, WANG Hua3, LI Ling3, LIN Xuyun2, LONG Likun2, WENG Kenan4. LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, jilin university, changchun 130012, China 2. Institute of Genetics and Cytology, Northeast Normal university, changchun 130024. China 3.{4. of Life Science, jilin university, changchun 130012, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 51064., China 1. National Laboratory of Superhard Materials Jilin University Changchun 130012 China 3. college of Life Science Jilin University Changchun 130012 China 2. Institute of Genetics and Cytology Northeast Normal University Changchun 130024 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together withthe original line (Bijing38), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. Southern blot analysis using diverse sequences, including twocellular genes (S2 and S3), a set of retrotransposons (Osr7, Osr36, Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.

Stable isotopic composition of the intrusive massive sulphide deposits

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Chinese Science Bulletin 1997年第6期42卷 476-478页

作者： MENG LiangyiDepartment of Geology, changchun university of earth sciences, changchun 130026, China Department of Geology Changchun University of Earth Sciences Changchun China

A new genetic type of deposits, intrusive massive sulphide deposits, is found to be genetically linked with intermediate-acid intrusive rocks. Copper is the main industrial element, and gold is also important and can sometimes make up single gold deposits. This type of massive sulphide deposits is widely distributed in middle-lower reaches of the Yangtze River. The famous mines are Wushan, Chengmenshan and Dingjiashan in Jiangxi Province, Xinqiao and Dongguashan in Anhui Province. The deposits are mostly hosted in

关键词： intrusive massive sulphide deposits intermediate-acid intrusive rocks stable isotopes.

The Geological-Geophysical-Geochemical Exploration Model of the Nancha Type Gold Deposit in Tonghua Area, jilin Province

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Global Geology 2001年第2期6卷 151-158页

作者： GUAN Jian (college of earth sciences, jilin university,{4., P.R.China) college of earth sciences Jilin University Changchun 130061 P.R. China

The Laoling metallogenic belt is very important for precious and non-ferrous metal deposits in jilin province, and the Nancha gold deposit found and explored in recent years in the metallogenic belt is the most representative one in the belt. The geological controls of the deposit,and the geophysical and geochemical ore searching indicators are summarized, and a synthetic exploration model, involving data from geology, geophysics and geochemistry and so on, is set up in the paper based on the study on the geological controls of the ores, on the measurement of geophysical properties of the ores and host rocks, on the observation of geophysical field around the mineralized district and on the research of the geochemical characte^ristics of the deposit. It is believed to be of significance to the exploration of the similar deposits in the metallogenic belt.

关键词： Nancha gold deposit exploration model S- shaped fracture zone geophysics geochemistry