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seismic interpretation and hydrocarbon accumulations implication of the Miocene Meishan Formation reefs in southern Qiongdongnan Basin, northern South China Sea

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Journal of Palaeogeography 2017年第3期6卷 206-218页

作者： Yang-Wei Feng Hong-Jun Qu Gong-Cheng Zhang Ren-Hai Pu Xi'an center of Geological survey China Geological Survey Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits MLR Geological research center of Orogenic Belt China Geological Survey Department of Geology Northwest University research center of CNOOC (China)

Numerous moundy reflections were found at the Upper Meishan Formation in southern Qiongdongnan Basin, South China Sea which are suspected reefs. However, no common understanding on the seismic and geologic interpretation was acquired. Based on seismic reflection identification, geometrical configuration description, wave impedance inversion, forward simulation, analysis of reef-building sedimentary environments and pseudomorph identification, these suspected-reef moundy reflections were studied in *** types of reefs were recognized, i.e., patch reef, platform-edge reef, and pinnacle reef. They have some typical characteristics of reefs, including moundy or lenticular shape, clear outline with crest and canal, internal foreset bedding, bidirectional uplap between limbs, and strong reflection at top and bottom. The patch reefs are of moundy seismic facies, with moderateestrong amplitude and moderate frequency, and distribute at the higher part of southern slope belt. Fore-reef and back-reef of patch reefs are slightly asymmetrical being perpendicular to palaeo-bathymetric orientation; while symmetrical to slightly asymmetrical being parallel to the palaeo-bathymetric orientation, and the wave impedance value is about 7 kg/m^3×m/***-edge reefs are of flat-moundy seismic facies with strong amplitude and moderate frequency, which develop at the carbonate platform edge of higher part of southern slope belt, and the wave impedance value is about 7.5 kg/m^3×m/s. Pinnacle reefs grow up on volcanic cones, forming the complex of pinnacle reef and volcanic cone. The Miocene Meishan Formation reefs in southern Qiongdongnan Basin, northern South China Sea, with high quality sourceereservoireseal assemblages, have good petroleum exploration prospects.

关键词： Meishan Formation Patch reef Platform-edge reef Pinnacle reef Hydrocarbon accumulations implication Qiongdongnan Basin South China Sea

Surface Wave Group Velocity Tomography Imaging from Ambient Noise for Fujian Province and Its Adjacent Areas

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Earthquake research in China 2019年第1期33卷 52-61页

作者： ZHANG Lina LUO Yan CHEN Zhiyong XIE Zhizhao ZHOU Lanjie ZENG Xiangfang xiamen seismic survey research center Fujian Earthquake Agency Institute of Earthquake Forecasting CEA Fujian Earthquake Agency State Key Laboratory of Geodesy and Earths Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences

Two-month continuous waveforms of 108 broadband seismic stations in Fujian Province and its adjacent areas are used to compute noise cross-correlation function(NCF). The signal quality of NCF is improved via the application of time-frequency phase weighted stacking. The Rayleigh and Love waves group velocities between 1 s-20 s are measured on the symmetrical component of the NCF with the multiple filter method. More than 5,000 Rayleigh wave dispersion curves and about 4,000 Love wave dispersion curves are obtained and used to invert for group velocity maps. This data set provides about 50 km resolution that is demonstrated with checkerboard tests. Considering the off great circle effect in inhomogeneous medium, the ray path is traced based on the travel time field computed with a finite difference method. The inverted group velocity maps show good correlation with the geological features in the upper and middle crust. The Fuzhou basin and Zhangzhou basin showed low velocity on the short period group velocity maps. On the long period group velocity maps, the low velocity anomaly in the high heat flow region near Zhangzhou and clear velocity contrast across the Zhenghe-Dapu faults, which suggests that the Zhenghe-Dapu fault might be a deep fault.

关键词： Fujian Ambient noise Surface wave group velocity Tomography imaging

research on Micro-relief of Active Faults on the Coast of Southeast Fujian and Its Adjacent Area

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Earthquake research in China 2007年第2期21卷 210-224页

作者： Huang Qingtuan Zheng Shaopeng xiamen Seismological survey and research center Xiamen 361021 China

On the southeast coast of Fujian and its adjacent area, the NE-trending Changle-Zhao＇an fault zone and several NW-trending faults that are genetically related to the former are well developed. With micro-relief analysis, the paper deals with the Quaternary activity of the faults and the tectonic stress field since the late Pleistocene in this region. The results indicate that the micro-relief of the NE-trending Changle-Zhao＇an fault zone and the genetically related NW-trending faults is characterized by vertical and horizontal movements since the Quaternary; the faults in the region have undergone two active stages since the Quaternary, i.e. early Quaternary and late Pleistocene; since the late Pleistocene, the movement of the NE- trending faults showed a right-lateral strike-slip, while that of NW-trending faults a left-lateral strike-slip, indicating a NWW-SEE oriented horizontal principal stress of the regional tectonic stress field.

关键词： Active fault Micro-relief The southeast coast of Fujian

Expression of strain tensor in orthogonal curvilinear coordinates

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Geodesy and Geodynamics 2010年第1期1卷 48-56页

作者： Xuyan Liu Yingfeng Ji Quanqiang Liang Earthquake Administration of Fujian Fuzhou 350003 China xiamen research center of Earthquake survey Xiamen 361021 China

Based on an analysis of connotation and extension of the concept of the orthogonal curvilinear coordinates, we have deduced a platform of strain tensor expression of Cartesian coordinates, which turns out to be a function of Lame coefficient and unit vector. By using transform matrix between Cartesian coordinates and orthogonal eurvilinear coordinates, we have deduced a mathematical expression for correcting displacement vector differential in orthogonal curvilinear coordinates, and given a general expression of strain tensor in orthogonal curvilinear coordinates.

关键词： Orthogonal Curvilinear Coordinates ( OCC ) Cartesian coordinates strain tensor transformation matrix universal expression

Surface water exchanges in the Luzon Strait as inferred from Lagrangian coherent structures

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Acta Oceanologica Sinica 2020年第11期39卷 21-32页

作者： Zhehao Zheng Wei Zhuang Jianyu Hu Zelun Wu Changjian Liu State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Joint center for Ocean Remote Sensing University of Delaware-Xiamen UniversityNewarkDE 19716USA South China Sea Marine survey and Technology center Ministry of Natural ResourcesGuangzhou 510300China

This study presents a Lagrangian view of upper water exchanges across the Luzon Strait based on the finite-time Lyapunov exponents(FTLE)fields computed from the surface geostrophic *** Lagrangian coherent structures(LCSs)extracted from the FTLE fields well identify the typical flow patterns and eddy activities around the Luzon *** addition,they reveal the intricate transport paths and fluid domains,which are validated by the tracks of satellite-tracked surface drifters and cannot be visually recognized in the velocity *** FTLE fields indicate that there are mainly four types of transport patterns near the Luzon Strait;among them,the Kuroshio northward-flowing"leaping"pattern and the clockwise rotating"looping"pattern occur more frequently than the"leaking"pattern of the direct Kuroshio branch into the SCS and the"outflowing"pattern from the SCS to the *** eddy shedding events of the Kuroshio at the Luzon Strait are further analyzed,and the importance of considering LCSs in estimating transport by eddies is *** anticyclonic eddy(ACE)shedding cases reveal that ACEs mainly originate from the looping paths of Kuroshio and thus could effectively trap the Kuroshio water before eddy *** provide useful information to predict the positions of the upstream waters that finally enter the *** contrast,LCS snapshots indicate that during the formation of cyclonic eddies(CEs),most CEs are not connected with the pathways of Kuroshio ***,the contribution of CEs to the surface water exchanges from the Pacific into the SCS is tiny.

关键词： Lagrangian coherent structures(LCSs) Kuroshio Luzon Strait transport pathways particle tracking

Earthquake fault framework and seismotectonics of the Songpan-Garze region since 1900

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Earthquake Science 2012年第5期25卷 451-458页

作者： Jiasheng Zhang Weijun Gan Minghua Zhang Xiongnan Huang Feng Liu Institute of Geology China Earthquake Administration Development research center of China Geological survey

Based on 4 781 observed faults （〉2 km length） from a 1：200 000 scale digital geologic map and 5 220 recorded seismic events since the year 1900, 993 earthquake faults are identified within the triangular Songpan-Garze study region. The study area is delineated by the nearly EW-trending East Kunlun fault zone to the north, the NW-trending Xianshuihe fault to the south and the NE-trending Longmenshan thrust belt to the east. seismicity changes along these earthquake faults, spanning four 10-year intervals since 1970, show that following a strong earthquake swarm, which occurred in the Huya area in the mid-1970s, seismic activity increased from north to south, and migrated eastward along each major strike-slip fault zone. GPS observation data before 2008 indicate a displacement rate across the Xianshuihe fault zone to the south of -6.5- 8.6 mm/a, whereas across the East Kunlun fault zone to the north it was -1.8- 2.2 mm/a. The May 12, 2008 Ms8.0 Wenchuan earthquake, which occurred in the southeast corner of the study region, was the result of stable, high-speed left-lateral displacement along the Xianshuihe fault zone, and a sharp eastward bend of the fault trend in response to the presence of crystalline rocks in the Kangding area. Therefore, the 110-year established seismotectonic framework of the Songpan-Garze region can be defined by a network of various earthquake faults and the structural relations of the local earthquake activities.

关键词： Songpan-Garze region earthquake fault GPS Wenchuan earthquake

An ecological survey of the abundance and diversity of benthic macrofauna in Indonesian multispecific seagrass beds

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Acta Oceanologica Sinica 2018年第6期37卷 82-89页

作者： LIN Junhui HUANG Yaqin ARBI Ucu Yanu LIN Heshan AZKAB Muhammad Husni WANG Jianjun HE Xuebao MOU Jianfeng LIU Kun ZHANG Shuyi Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China research center for Oceanography Indonesian Institute of Sciences Jakarta 14430 Indonesia

Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes（56 species, 26% of total individual numbers）, decapods（20 species, 9% of total numbers） and amphipods（18 species, 35% of total numbers）. Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two ma

关键词： benthic macrofauna diversity abundance community structure seagrass bed North Sulawesi

Distribution of phytoplankton in the East China Sea and the southern Yellow Sea in spring in relation to environmental variables and dimethylsulfide compounds

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Acta Oceanologica Sinica 2022年第6期41卷 41-53页

作者： Jiawei Zhang Yanghang Chen Xueyan Ren Vishal Patil Lin Sun Xuesong Li Junrong Liang Jun Zhang Yahui Gao Changping Chen School of Life Sciences Xiamen UniversityXiamen 361102China Key Laboratory of the Coastal and Wetland Ecosystems of Ministry of Education Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Laboratory of Marine Biology and Ecology Third Institute of OceanographyState Oceanic AdministrationXiamen 361005China Eco-Environmental Monitoring and research center Pearl River Valley and South China Sea Ecology and Environment AdministrationMinistry of Ecology and EnvironmentGuangzhou 510610China

The coastal ecosystems are highly sensitive to climate change and are usually influenced by variations in phytoplankton communities and water physiochemical *** the present study,the phytoplankton community,chlorophyll a(Chl a)and their relationships with environmental variables and dimethylsulfide(DMS)and dimethylsulfoniopropionate(DMSP)were investigated in spring 2017(March 24 to April 16)in the East China Sea(26.0°-33.0°N,120.0°-128.0°E)and southern Yellow Sea(31.0°-36.0°N,120.0°-125.0°E).The spatial distributions of phytoplankton species composition and cell density were investigated by qualitative and quantitative methods and were compared with historical data to study phytoplankton species succession in the survey *** results showed that there were 275 phytoplankton species belonging to 90 genera and 6 phyla in the survey area,of which 208 species belonged to 62 genera of Bacillariophyta and 56 species belonged to 20 genera of *** dominant phytoplankton species were Skeletonema dohrnii,Chaetoceros vanheurckii and Prorocentrum *** phytoplankton cell densities ranged from 0.06×10^(4)cells/L to 418.73×10^(4)cells/L,with an average value of 21.46×10^(4)cells/*** spring,the average ratio of Bacillariophyta/Pyrrophyta was41.13 for the entire study *** areas with high phytoplankton cell density were mainly distributed in the northern South Yellow Sea and offshore waters of the East China *** to a canonical correspondence analysis among phytoplankton and environmental parameters,the water Chl a concentrations were notably consistent with phytoplankton cell density(P<0.001),and both showed significant negative correlations with salinity and nitrite(P<0.05)and significant positive correlations with dissolved oxygen and pH(P<0.001).There was a significant positive correlation between diatom(both in cell density and in dominant species)and DMS(P<0.05),which indicated that diatoms play a greater role in DMS production in t

关键词： phytoplankton distribution East China Sea southern Yellow Sea dimethylsulfoniopropionate

Deep seismic Exploration in the Taiwan Straits: The HX9 survey Line Experiment and Preliminary Results

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Earthquake research in China 2015年第4期29卷 459-469页

作者： Yan Pei Zhang Yifeng Li Puchun Wang Sun research center of Earthquake Reconnaissance in xiamen Earthquake Administration of Fujian Province

By using an offshore large volume air-gun seismic source, onshore seismic stations( including mobile stations and permanent stations) and ocean bottom seismometers,a deep seismic exploration experiment was carried out for the first time in the Taiwan Straits. Results show that seismic stations can receive seismic signals from the air-gun arrays of the "YANPING Ⅱ"scientific investigation ship from as far as 280 km *** of thousands of high quality seismic data items were obtained successfully and different types of P-wave seismic phases were identified. A one-dimensional crustal structure model of the survey profile HX9 shows that the crustal structure,which is reflected by Pc and Pm P reflection waves from two velocity discontinuities and basement refraction wave( Pg) constitutes the basic characteristic of the crustal structure in this region. The depths of Conrad discontinuity and Moho discontinuity are respectively16. 0km- 17. 5km and 28. 0km- 29. 5km.

关键词： Taiwan Straits Deep seismic exploration Air-gun seismic source Crustal structure