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Coupling controls of neotec-tonism and paleoclimate on the Quaternary sediments of the Yangtze (Changjiang) coast

Science Bulletin 2005年第16期 105-114页

作者： WANG Zhangjiao1, CHEN Zhongyuan2, WEI Zixin3. WANG Zhanghua1 & WEI Taoyuan1 1. Department of Geography, East china Normal University, shanghai 200062, china 2. State Key laboratory for Estuarine and Coastal Research, East china Normal University, shanghai 200062, china 3. shanghai institute of geological survey, shanghai 200072, china

Attempt has been made to discuss the coupling relation of neotectonism and paleoclimate that have played a critical role in controlling the Quaternary sediment distribu-tion and sedimentary facies evolution on the Yangtze coast. On the basis of petrological analysis, up to six sedimentary cyclicities have been identified in the Quaternary sediment boreholes on the time scale of 0.4―0.5 Ma. The lower sedi-mentary cyclicities (Pliocene to Early Pleistocene) are char-acterized largely by thicker gravelly coarse sands, topped by thinner fine silt and silty clay. Gravels are very angular and clayey gravels prevail. Sediments are usually of poor sorting, rich in log fragments and have no microfossils. Bedload as denoted by C-M plot occurs throughout the section. This evidence represents the alluvial fan sedimentation which took place as the basin began to subside. The middle sedimentary cyclicities (often including Early to Middle Pleistocene) con-sist of basal gravelly sands and clayey silt at the middle and upper sediment sections. Sorting becomes relatively better, and foraminifer appears sporadically. C-M plot reveals the mixture of sediment transport media via bedload, saltation and suspension, representing sedimentation of braided river system at the early stage and subsequently, the sedimentation of meandering river pattern. The upper sedimentary cyclic-ities (including Late Pleistocene to Holocene) comprise basal gravelly sands (exclusive of the Holocene sediment) and thick fine sand and silty clay on the upper section. Sorting becomes fine and foraminifer appears throughout the sediment sec-tion. C-M plot shows that saltation and suspension serve as the main sediment transport media in the sediment section and bedload transport weakens. These evidence the sedi-mentation of meandering river pattern near coast during Late Pleistocene and Holocene time, when marine transgres-sion invaded into the paleoriver valleys, which often forms drowned-valley facies and shallo

关键词： Quaternary sediments grain size neotectonic subsidence paleoclimate/sea-level fluctuations Yangtze delta.

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Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3. WANG Fei4, SUN Yangui5, WEI Xiangdong3.& XING Zuoyun6 1. Division of Granite Geology, china geological survey, Yichang 443.03. china 2. Information Center of Ministry of Land and Resources, Beijing 100812, china 3. geological survey of Henan Province and institute of geological Research of Henan Province, Zhengzhou 450053. china 4. geological institute, china Seismological Bureau, Beijing 100029, china 5. geological survey institute of Qinghai Province, Xining 81003., china 6. china University of Geosciences, Wuhan 43.074, china Division of Granite Geology China Geological Survey Yichang China Information Center of Ministry of Land and Resources Beijing China geological survey of Henan Province and institute of geological Research of Henan Province Zhengzhou China geological institute China Seismological Bureau Beijing China geological survey institute of Qinghai Province Xining China china University of Geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±3.)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

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Determination of tectonic background for sedimentary basin from sandstone geochemistry

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Chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1, K. Stattegger 2 and LI Wenhou 3.1. Laboratory of Marine Geology, Tongji University, shanghai 200092, china 2. geological and Paleontological {3., University of Kiel, 24118 Kiel, Germany 3. Department of Geology, Northwest Unive Laboratory of Marine Geology Tongji University Shanghai China geological and Paleontological institute University of Kiel Kiel Germany Department of Geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.

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The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3.and Xin-Wu Cao1,2 1 shanghai Astronomical Observatory, Chinese Academy of Sciences, shanghai 20003., china 2 Joint {3. for Galaxy and Cosmology (JOINGC) of SHAO and USMC, shanghai 20003., china 3.Graduate School of the Chinese Academy of Sciences, Beijing 100049, china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

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^(40)Ar/^(3.)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science china Earth Sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2, 3.& YANG Nong1 1. institute of Geomechanics, Chinese Academy of geological Sciences, Beijing 100081, china 2. institute of Geology, Chinese Academy of geological Sciences, Beijing 10003., china 3. institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12-10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

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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 {3. survey, Zhengzhou 450007, china 3. State Key Laboratory of {3. Processes and Mineral 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 Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan institute of geological survey Zhengzhou China State Key Laboratory of geological Processes and Mineral Resources at china University of Geosciences Wuhan China Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 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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The computation of maximum wind speeds of typhoon

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Acta Oceanologica Sinica 1990年第1期9卷 69-79页

作者： Chen Kongmo and Qin Zenghao Third institute of Oceanography, State Oceanic Administration, Xiamen, china shanghai Typhoon institute, shanghai, china

-At present, it is still difficult to obtain an accurate maximum wind speed of typhoon with modern means,such as satellite survey , radar tracing and airplane reconnaissance. The performance of statistical equation established with observational maximum wind speed and the central pressure of typhoon is unstable ,and it is unreliable in operational use. Therefore a general pressure field model of typhoon is introduced in this paper based on atmospheric motion equations and formulas are derived for computing the maximum wind speed around typhoon center over sea surface . The theoretical curves derived from these formulas are in good agreement with those using the statistic empirical curves of typhoon pressure-wind relations over the western Pacific. Tests were conducted for typhoons which occurred in 1973.and in 1983.and the strongest typhoons selected each year during 1970 and 1978,the results were satisfactory. Meanwhile the analyses of computing results showed that the effect of Coriolis force could be negligible and the eccentric-elliptical pressure structure of typhoon could be treated as circular symmetric.

关键词： over

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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 Resources, Nanjing 210016, china {3. survey of No. 3.{3. Party, Xinjiang, Kurle 841000, china) Postgraduate School of Guizhou University Guiyang 550025 China Nanjing institute of Geology and Mineral Resources Nanjing 210016 China geological survey of No. 3.geological Party Xinjiang Kurle 841000 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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Paleoenvironmental information recorded by pollen in B-3.C gravity core in Okinawa Trough

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Chinese Science Bulletin 2001年第11期46卷 938-942页

作者： SONG Changqing, SUN Xiangjun & Yoshiki SaitoNational Natural Science Foundation of china, Beijing 100085, china Open Lab of Marine Geology, Tongji University, shanghai 20003., china institute of Botany, Chinese Academy of Sciences, Beijing 100093. china geological survey of Japan, Higashi 1-1-3. Tsukuba, Ibaraki, 3.5-8567,Japan National Natural Science Foundation of china Beijing China Open Lab of Marine Geology Tongji University Shanghai China institute of Botany Chinese Academy of Sciences Beijing China geological survey of Japan Ibaraki Japan

Based on pollen records in B-3.C gravity core, environmental change since 9500 aBP of Okinawa Trough and its adjacent islands was derived. The result showed that the most time during this period was in a warm temperate climate except in middle Holocene (6800-4400 aBP) that was under subtropical climate control. During 9500-83.0 aBP and 3.00-2000 aBP periods, it appeared colder and drier than the rest time. The original area of pollen sources surrounding Okinawa Trough was covered by evergreen and deciduous broadleaf forest alternatively with mixed broad-leaf-conifer forest distributed in high mountainous areas. Usually, these three kinds of forests existed at the same time with difference in altitude. Pollen from subtropical and tropical plants increased obviously in about 5000-6000 aBP, reflecting a great lifting of vegetation zone and expansion of evergreen broad-leaf forest in the study area. However, there was a slight descending of plant zone and shrinking of evergreen broadleaf forest during

关键词： environmental change Holocene pollen Okinawa Trough.

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Ancient Changjiang channel system in the East china Sea continental shelf during the last glaciation

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Science china Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3. YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean University of china, Qingdao 266003. china 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique, Qingdao 266003. china 3. Qingdao {3. of Marine Geology, Qingdao 266071, china 4. College of Marine Environment, Ocean University of china, Qingdao 266003. china 5. First survey Team of Marine Geology, shanghai Bureau of Petroleum, shanghai 201208, china College of Marine Geo-science Ocean University of China Qingdao China Shandong Key Laboratory of Sea Floor Resource and Exploration Technique Qingdao China Qingdao institute of Marine Geology Qingdao China College of Marine Environment Ocean University of China Qingdao China First survey Team of Marine Geology Shanghai Bureau of Petroleum Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East china Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

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