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Correlation of Upper Devonian and Lower Carboniferous Depositional Sequences in Different Facies Belts on Southern Margin of Upper Yangtze Platform

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Journal of Earth Science 1999年第2期18卷 38-46页

作者： Wang Xunlian Department of geology and mineral resources,{3. University of Geosciences, Beijing 100083

A fundamental problem in sequence stratigraphy is whether the sequences are global in extent and whether the sea level changes are eustatic in nature. Study on the Upper Devonian and Lower Carboniferous depositional sequences in different facies belts on the southern margin of the Upper Yangtze platform shows that different orders of sequences possess distinctive distribution and correlation in space, although the sea level changes in various orders of sequences may be primarily global in nature. The present paper regards the distribution in space, especially in different facies belts, as a criterion for defining and recognizing the various orders of sequences. The orthosequence (third order sequence) is probably global in nature, which may be discerned in various depositional facies belts on the continental margin and can be correlated over long distances, sometimes maybe worldwide. Commonly, correlation of the subsequences (fourth order sequences with time interval of 0.5 Ma to 1.5 Ma) is difficult in different facies belts, although some of them are probably also worldwide in distribution. A subsequence should be distinguishable and correlatable within at least one facies belt. The higher order sequences, including parasequences (fifth order sequences) and microsequences (sixth order sequences), are regional or local in distribution. They may have reflected the longer and shorter Milankovitch cycles respectively. Orthosequences and subsequences are usually recognizable in different facies belts, while parasequences and microsequences may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits.

关键词： facies belt orthosequence subsequence parasequence microsequence meter scale cyclothem Milankovitch cycle.

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FOSSIL HAGLIDAE(ORTHOPTERA)IN china

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Science china Chemistry 1982年第10期29卷 1118-1132页

作者：洪友崇 Tianjin Institute of geology and mineral resources Ministry of Geology

The present paper discusses Haglidae (Orthoptera) and its stratigraphic and geographicdistributions in china. Basing on our fossil specimens and the known fossil records of insectsthe author tries to discuss the taxonomy of the family Haglidae, including its subfamilies andgenera. Four new genera and seven new species are established.

关键词： Cu FOSSIL HAGLIDAE ORTHOPTERA)IN china length

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing Institute of geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Henan Institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and {3. resources at china University of Geosciences, Wuhan 43.074, china 4. Faculty of Material Sciences and Chemical Engineering, china University of Geosciences, Wuhan 43.074, china 1. Nanjing Institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and mineral resources at china University of Geosciences Wuhan 430074 China 4. Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Geological Evidence for the Presence of the Emperor Event in china

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Acta Geologica Sinica(English Edition) 1993年第2期67卷 235-244页

作者： Ge Tongming, Fan Limin and Liu Jian Guangzhou Marine Geological Survey, Ministry of geology and mineral resources of{3., Guangzhou Guangzhou Marine Geological Survey Ministry of Geology and Mineral Resources of China Guangzhou

The presence of the reversals of the geomagnetic field within the Brunhes is indicated by paleomagnetic stuides on Cenozoic volcanic rocks in the Leizhou Peninsula, loess strata and Quaternary marine sediments in the Pearl River Mouth basin in china. These regional reversals occured at 0.58±0.13.Ma, 0.45 Ma and 0.47—0.48 Ma respectively according to the results of K-Ar isotopic dating and climatostratigraphic and biostratigraphic analyses. The reversals equivalent to the Emperor Event is suggested.The reversals revealed in different regions with various lithologic characters in china prove that the Emperor Event is a global reversal event rather than a geomagnetic excursion, and its confirmation will permit a precise definition of the Middle/Late Pleistocene boundary.

关键词： Brunhes polarity reversal Emperor Event

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DIVISION and CORRELATION OF MIDDLE—UPPER PROTEROZOIC IN WESTERN SECTION OF MIDDLE QILIANSHAN

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甘肃地质 1985年第S1期 161-162页

作者： Institute of geology bureau of geology and {3. resources of Gansu

Qilianshan is the important mountain in Northwestern china,where theUpper Precambrian is well developed,in which especially in the westernsection of middle Qilianshan is extensive distributed,where the Upper Pre-cambrian succession iS complete in comparison,this is the important areafor researching into a geosyclinal type deposit of Middle—Late Proterozoicera.

关键词： UPPER PROTEROZOIC IN WESTERN SECTION OF MIDDLE QILIANSHAN DIVISION and CORRELATION OF MIDDLE

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On Tectonogeomorphology of china

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Journal of Earth Science 1995年第1期14卷 64-70页

作者： Wan Tianfeng(Department of geology and mineral resources,{3. University of Geosciences, Beijing 100083.

With the deepening of research in the tectonic evolution and stress fields of china in Meso-Cenozoic, some aspects of the Previous conclusion about the tectonogeomorphology of china are found to be open to question. The author considers that the Sichuanian stage (13.-52 Ma ) is the embryonic stage for forming the recent landform in eastern china;the appearance of the mountain ranges and drainage basin areas trending in east-west are the results of the north - south directional extension during the North Sinian stage(52 - 23.3.Ma );the formation of five mega - Step landforms from the Qinghai - Xizang Plateau to Pacific ocean and the seafloor spreading basins in the eastern margin of Asian continent as well as the l- up of drainage systems of both Yangtze and Yellow rivers are related to the northward compression, cast-west trending extension and the isostatic compensation of crust during Himalayan Stage (23.3.0.73.Ma ). Through the above three Stages of tectonic processes, a framework of landform of china finally took shape in the main.

关键词： tectonogeomorphology stress field mountain range drainage basin extension zone of continental margin

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3.& YE Xianren2 1. resources and Environmental School, Lanzhou University, Lanzhou 73.000, china 2. Key Laboratory of Gas Geochemistry, Institute of geology and Geophysics, Chinese Academy of Sciences, Lanzhou 73.000, china 3. College of resources Science & Technology, Beijing Normal University, Beijing 100875, china 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources Science & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Control of Interior Sources on Time-Bound Characteristics of mineralization in Southwest Yangtze Massif

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Journal of Earth Science 1999年第1期18卷 84-89页

作者： Yu Bingsong Department of geology and mineral resources,{3. University of Geosciences, Beijing 100083

Strata bound ore deposits of Au, Ag, Hg, Sb, As, Sn, Pb and Zn in southwest Yangtze massif are concentrated in Cambrian, Devonian, Upper Permian to Lower Triassic and rarely in other horizons, showing a strong time bound feature. The metallogenic elements are highly enriched in these host strata and limited in other horizons. Isotope researches indicate that the metallogenic elements in the ore deposits mainly come from the host strata. The studies of trace elements in the host mudstone show lower w (Th)/ w (Sc), w (Th)/ w (U) ratios, higher mafic elements (such as Cr, Ni, Co) mass fractions than the average values of the same kind of rocks in the upper crust and the research area. The chondrite normalized REE patterns of mudstone in the host strata are quite different from the common mudstones and shales with relatively steep HREE slopes (relatively high w (Tb) n/ w (Yb) n ratios, between 1.48 and 2.00) and no or slightly negative Eu anomalies (high δ (Eu) ratios, between 0.79 and 0.89). The NASC normalized REE patterns of siliceous rocks in the host strata show the HREE enrichment (the w (La) n/ w (Yb) n ratios are less than 1), a little Eu positive anomalies and Ce depletion with high abundances of As, Se, Sb and Ba elements, which shows the hydrothermal deposit features. The NASC normalized REE patterns of the mudstone in the host strata are very similar to those of the hydrothermal siliceous rocks and to those of the tuffs and basalts except the higher total REE mass fractions. All of these geochemical characteristics suggest the existence of interior sources pouring into basin when the host strata were deposited. The research of basin evolution also indicates that the host strata were deposited in the pulling apart periods. It can be realized from these facts that the degree of enrichment and deficiency of the elements in the normal depositional strata is very limited, and it is only the particular horizons correspo

关键词： interior source time bound characteristic mineralization southwest Yangtze massif.

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Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 550025, china Nanjing Institute of geology and mineral {3., Nanjing 210016, china Geological Survey of No. 3.Geological Party, Xinjiang, Kurle 841000, china) [a]Postgraduate School of Guizhou University Guiyang China [b]Nanjing Institute of geology and mineral resources Nanjing China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3.1. 4 mm wide; their wrinkled lamellae are microfine with 3.10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

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Sequence Boundary:Its Significance in Stratigraphic Subdivision,Correlation and Classification

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Journal of Earth Science 1995年第2期14卷 60-67页

作者： Mei ShilongDepartment of geology and mineral resources.{3. University of Geosciences. Beijing 100083

Sequence boundary is studied in detail in reference to the Permian Guadalupian Lopingian boundary, based on high resolution correlation of conodont zones. A conceptual synchronous stratigraphic boundary, corresponding to the age of the sequence boundary dated in the conformable portion of the sequence boundary, is defined as the sequence chronostratigraphic boundary (SCB). The sequence boundary is proved to be dual in nature in regards to tin-synchrony and diachroneity of stratigraphic boundaries. The merits of the sequence boundary in stratigraphic subdivision, correlation and classification are elucidated in comparison with the lithostratigraphic boundary, the biostratigraphic boundary and the traditional approach of the global stratotype section and point (GSSP ). By integrating the virtues of the sequence boundary and the GSSP, it is proposed that the GSSP should be established in the conformable portion of the related sequence boundary. The boundary established in light of this approach is defined as the best natural boundary. The analysis of the sequence boundary leads to the conclusion that sequence stratigraphy is a regional and transitional stratigraphic system between local lithostratigraphy and global chronostratigraphy. Therefore, a new tripartite stratigraphic classification scheme is tentatively proposed.

关键词： sequence boundary sequence chronostratigraphic boundary - global stratotypesection and point (GSSP ),best natural boundary new tripartite stratigraphic classificationscheme .

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