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Experimental Study on the Relationship Between Gas Hydrate Saturation and Water Permeability in Sediments

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地学前缘 2009年第S1期16卷 228-228页

作者： Jian zhang,Yuguang Ye,Gaowei Hu,Shaobo Diao,Changling Liu,Qiang Chen 1.College of marine Geosciences,Ocean University of china,qingdao 266003,china. 2.qingdao institute of marine geology,qingdao 2.6071,china 3.Faculty of Earth sciences,china University of Geosciences(Wuhan),Wuhan 430074,china

A new experimental equipment is developed to study the relationship between gas hydrate saturation and water permeability in *** with dissolved methane is injected circularly into the sediments to form gas hydrate,and the gas hydrate saturation in sediment pores is measured by Time Domain Reflectometry(TDR).The experimental result shows that water permeability is barely influenced by gas hydrate when the saturation is below 30%.When the gas hydrate saturation in sediments pores is larger than 30%,water permeability

关键词： gas hydrate permeability saturation experiment

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冲绳海槽中段末次冰消期以来的元素地层

海洋学报 2003年第4期25卷 50-58页

作者：刘焱光孟宪伟李铁刚吴世迎王湘芹辛春英任红国家海洋局第一海洋研究所中国科学院海洋研究所山东青岛266071

在对冲绳海槽中段180号岩心进行高分辨率取样的基础上,测定了沉积物中的23个地球化学指标,通过对各元素与Al_2O_3含量的比值在岩心中的垂向变化规律的分析,结合氧同位素、黏土矿物、粒度、AMS^(14)C测年和R型因子分析方法,可将岩心从上... 详细信息

在对冲绳海槽中段180号岩心进行高分辨率取样的基础上,测定了沉积物中的23个地球化学指标,通过对各元素与Al_2O_3含量的比值在岩心中的垂向变化规律的分析,结合氧同位素、黏土矿物、粒度、AMS^(14)C测年和R型因子分析方法,可将岩心从上至下划分为5层:第1,3,5层具有相似的元素组合特征,第2,4层为明显的异常变化层位,将元素的地球化学行为、元素组合与物质来源联系起来,并与碎屑矿物、古生物资料对比,探讨岩心中元素组合垂向变化的制约因素,据此讨论了冲绳海槽中段末次冰消期以来陆源、火山源及生物源物质的分布规律。结果表明,冲绳海槽中段末次冰消期以来的沉积物来源以陆源物质为主,但在局部层位可因生源组分和火山源组分的强烈影响而发生实质性的变化。

关键词：冲绳海槽元素地层学海洋沉积学末次冰消期海洋地球化学

An accurately delineated Permian-Triassic Boundary in continental successions

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Science china Earth sciences 2007年第9期50卷 1281-1292页

作者： YIN HongFu1, YANG FengQing2, YU JianXin2, PENG YuanQiao1, WANG ShangYan3 & zhang SuXin1 1 laboratory of Biological and environmental geology, china University of Geosciences, Wuhan 430074, china 2 State key laboratory of Geological Process and Mineral Resources, china University of Geosciences, Wuhan 430074, china 3 Geological Survey of Guizhou Province, Guiyang 550011, china 1. laboratory of Biological and environmental geology China University of Geosciences Wuhan 430074 China 2. State key laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Geological Survey of Guizhou Province Guiyang 550011 China

The Permian-Triassic Boundary Stratigraphic Set (PTBST), characteristic of the GSSP section of Meishan and widespread in marine Permian-Triassic Boundary (PTB) sequences of South china, is used to trace and recognize the PTB in a continental sequence at Chahe (Beds 66f―68c). Diversified Permian plant fossils extended to the PTBST, and a few relicts survived above that level. Sporomorphs are dominated by fern spores of Permian nature below the PTBST, above which they are replaced by gymnosperm pollen of Triassic aspect. In the nearby Zhejue Section, the continental PTBST is charac- terized by the fungal 'spike' recorded in many places throughout the world. The boundary claybeds (66f and 68a,c) of the PTBST are composed of mixed illite-montmorillonite layers analogous with those at Meishan. They contain volcanogenic minerals such as β quartz and zircon. U/Pb dating of the upper claybed gives ages of 247.5 and 252.6 Ma for Beds 68a and 68c respectively, averaging 250 Ma. In con- trast to the situation in Xinjiang and South Africa, the sediment sequence of the Permian-Triassic tran- sition in the Chahe section (Beds 56―80) become finer upward. Shallowing and coarsening upward is not, therefore, characteristic of the Permian-Triassic transition everywhere. The occurrence of relicts of the Gigantopteris Flora in the Kayitou Fm. indicates that, unlike most marine biota, relicts of this pa- leophytic flora survived into the earliest Triassic. It is concluded that Bed 67 at Chahe corresponds to Bed 27 at Meishan, and that the PTB should be put within the 60-cm-thick Bed 67b④, now put at its base tentatively. This is the most accurate correlation of the PTB in continental facies with that in the marine GSSP.

关键词： Permian-Triassic Boundary, terrestrial sequence, U-Pb age, Chahe section, accuracy

Contribution of subducted Pacific slab to Late Cretaceous mafic magmatism in qingdao region,china:A petrological record

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Contribution of subducted Pacific slab to Late Cretaceous ma...

An epizootiological survey of White spot syndrome virus(WSSV)on copepod resting eggs and neonates by nested-PCR

中国科学院地质与地球物理研究所2008学术年会

作者： Jin zhang,Hong-fu zhang,~* Ji-feng Ying,Yan-jie Tang and Li-feng Niu State key laboratory of Lithospheric Evolution,institute of geology and Geophysics,chinese academy of sciences,PO Box 9825,Beijing 100029,china

The occurrence of the Pishikou mafic dike in the qingdao region,china provides important constraints on the origin of Late Cretaceous(86-78 Ma) mafic magmatism on the eastern North china *** Pishikou mafic dike is distributed in the Cretaceous Laoshan granitoid body,qingdao region and contains peridotitic and granulitic xenoliths, xenocrysts,and *** from the Pishikou mafic dike are basanites and have low SiO(2 wt%) and AlO(12.5 wt%) contents,and high MgO(>8 wt%),total alkalis (NaO + KO>4.8 wt%,NaO/KO>1),TiO(>2.5 wt%),CaO(>9 wt,%) and PO (>1 wt%).In trace element abundances,they are highly enriched in large ion lithophile elements(LILEs) and light rare-earth elements(LREEs)(ΣREE = 339-403 ppm,(La/ Yb) = 39-42) without high field strength element(HFSE) *** rocks have radiogenic Sr and Pb,and less radiogenic Nd isotopic compositions[(Sr/Sr);>0.7059,εNd≈2.7-3.8(Pb/Pb)≈18.0±0.1].The diagnostic elemental ratios,such as Nb/La, Nb/U,and Nb/Th,are compatible with those of mid-oceanic ridge basalts(MORBs) and oceanic island basalts(OIBs).Therefore,the Pishikou mafic dike has a geochemical feature completely different from those of the Early Cretaceous mafic dikes from the qingdao region,but similar to those of back-arc basalts from the Japan *** geochemical feature suggests that the Pishikou mafic dike was derived from an asthenosphere source, but contaminated by materials from the subducted Pacific *** discovery of this mafic dike thus provides a petrological evidence for the contribution of subducted Pacific slab to the Late Cretaceous magmatism in the qingdao region of the eastern North china craton.

关键词： asthenospheric source contribution of subducted Pacific slab Late Cretaceous mafic dike qingdao

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An epizootiological survey of White spot syndrome virus(WSSV...

U-Pb zircon geochronology of basaltic pyroclastic rocks from the basement beneath the Xisha Islands in the northwestern South china Sea and its geological significance

第六届世界华人虾蟹类养殖研讨会

作者： Jia-Song zhang~(a,b) Shuang-Lin Dong~(a1) Yun-Wei Dong~a Xiang-Li Tian~a Xiang-Yi Liu~(a.c) a The key laboratory of Mariculture,Ministry of Education Fisheries College,Ocean University of china,qingdao,P.R.china b key laboratory for Sustainable Utilization of marine Fisheries Resources,Ministry of Agriculture,Yellow Sea Fisheries Research institute,chinese academy of Fishery sciences,qingdao,P.R.china c Science and Technology Bureau of Rizhao,Rizhao,P.R.china

White spot syndrome virus(WSSV)is the most devastating and virulent viral agent threatening many commercially cultivated penaeid shrimp *** of the remarkable characteristics of WSSV is its wide host range among decapods which contributes to its wide geographical *** the present epizootiological study,14.67 % of the copepod resting egg specimens(20-30 resting eggs in each specimen)that were separated from sediments of shrimp farming ponds was found WSSV-positive by a nested-PCR *** addition,6 % of specimens (10-15 neonates fixed together in each specimen)of the neonates hatched from copepod resting eggs were positive for *** was a very high prevalence rate of WSSV infection(36.37 %)in neonate specimens that hatched from virus positive resting egg *** artificial infectivity experiment was also carried out in laboratory to validate the field study *** nested-PCR test revealed that WSSV-positive resulted in calanoid copepods,Acartia sp.,exposed to WSSV via the virus-phytoplankton adhesion *** positive results were also found in resting eggs and neonates reproduced from the WSSV-positive *** WSSV prevalence in copepod resting eggs and neonates was not high,our results indicate that the copepod resting eggs could serve as a disease reservoir during winter,allowing the virus to prevail in the following years.

关键词： WSSV Copepod Resting egg Neonate

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Acta Oceanologica Sinica 2024年第2期43卷 83-93页

作者： Yu zhang Kefu Yu Shiying Li Guangxi laboratory on the Study of Coral Reefs in the South china Sea Guangxi UniversityNanning 530004China Coral Reef Research Center of china Guangxi UniversityNanning 530004China School of marine sciences Guangxi UniversityNanning 530004China key laboratory of Ocean and Marginal Sea geology South China Sea Institute of OceanologyChinese Academy of ScienceGuangzhou 510301China

As one of the micro-blocks dispersed in the South china Sea(SCS), the basement of the Xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding of the pre-Cenozoic basement of the Xisha Islands. Well CK-1, a kilometer-scale major scientific drill in the Xisha Islands in the northwestern SCS, penetrated thick reefal limestone(0–888.4 m) and the underlying basement rocks(888.4–901.4 m). In this study, we present the zircon U-Pb ages of basement basaltic pyroclastic rocks from Well CK-1 in the Xisha Islands of the northwestern SCS to investigate the basement nature of the Xisha microblock. The basement of Well CK-1 consists of basaltic pyroclastic rocks on the seamount. The zircon grains yielded apparent ages ranging from ca. 2 138.9 Ma to ca. 36 Ma. The old group of zircon grains from Well CK-1 was considered to be inherited zircons. Two Cenozoic zircons gave a weighted mean 206Pb/238U age of(36.3 ± 1.1) Ma,Mean Squared Weighted Deviations(MSWD) = 1.2, which may represent the maximum age of the volcano eruption. The Yanshanian inherited zircons(116.9–105.7 Ma and 146.1–130.2 Ma) from Well CK-1 are consistent with the zircons from Well XK-1, indicating that the basement of Chenhang Island may be similar to that of Well XK-1. We propose that the Xisha micro-block may have developed on a uniform Late Jurassic metamorphic crystalline basement, intruded by Cretaceous granitic magma.

关键词： South china Sea Xisha Islands basaltic pyroclastic rocks zircon

Compositional and temperature variations of the Pacific upper mantle since the Cretaceous

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Acta Oceanologica Sinica 2016年第4期35卷 19-25页

作者： zhang guoliang key laboratory of marine geology and environment Institute of Oceanology Chinese Academy of Sciences laboratory for marine geology Qingdao National Laboratory for Marine Science and Technology

The geological evolution of the Earth during the mid-Cretaceous were shown to be anomalous, e.g., the pause of the geomagnetic field, the global sea level rise, and increased intra-plate volcanic activities, which could be attributed to deep mantle processes. As the anomalous volcanic activities occurred mainly in the Cretaceous Pacific, here we use basalt chemical compositions from the oceanic drilling（DSDP/ODP/IODP） sites to investigate their mantle sources and melting conditions. Based on locations relative to the Pacific plateaus, we classified these sites as oceanic plateau basalts, normal mid-ocean ridge basalts, and near-plateau seafloor basalts. This study shows that those normal mid-ocean ridge basalts formed during mid-Cretaceous are broadly similar in average Na8, La/Sm and Sm/Yb ratios and Sr-Nd isotopic compositions to modern Pacific spreading ridge（the East Pacific Rise）. The Ontong Java plateau（125–90 Ma） basalts have distinctly lower Na8 and143Nd/144 Nd, and higher La/Sm and 87Sr/86 Sr than normal seafloor basalts, whereas those for the near-plateau seafloor basalts are similar to the plateau basalts, indicating influences from the Ontong Java mantle source. The super mantle plume activity that might have formed the Ontong Java plateau influenced the mantle source of the simultaneously formed large areas of seafloor basalts. Based on the chemical data from normal seafloor basalts, I propose that the mantle compositions and melting conditions of the normal mid-ocean ridges during the Cretaceous are similar to the fast spreading East Pacific Rise. Slight variations of mid-Cretaceous normal seafloor basalts in melting conditions could be related to the local mantle source and spreading rate.

关键词： mantle temperature mantle source super mantle plume Cretaceous mid-ocean ridge basalt

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北海盆地油气成藏特征

海洋地质前沿 2012年第1期28卷 38-43页

作者：张生银龚建明李双林史基安中国科学院油气资源研究重点实验室兰州730000 青岛海洋地质研究所青岛266071 中国科学院研究生院北京100049

为了探讨北海盆地油气成藏特征,对前人在该区的大量研究成果进行了整理和分析,研究结果认为,北海盆地是一个以油为主的裂谷盆地,平面上具有"北油南气"的分布特征;发育多套油气圈闭类型,其中,二叠系镁灰岩统盐岩的分布和早白垩世晚期的... 详细信息

为了探讨北海盆地油气成藏特征,对前人在该区的大量研究成果进行了整理和分析,研究结果认为,北海盆地是一个以油为主的裂谷盆地,平面上具有"北油南气"的分布特征;发育多套油气圈闭类型,其中,二叠系镁灰岩统盐岩的分布和早白垩世晚期的反转运动控制了南部盆地的油气圈闭类型,而晚侏罗世—早白垩世的区域拉张运动控制了北部盆地的油气圈闭类型;北海盆地油气成藏类型大致可以划分为"新生古储"和"古生新储",北海南部盆地为"古生新储",北海北部盆地为"新生古储"和"古生新储"兼而有之的复杂的成藏组合类型。

关键词：成藏特征圈闭类型油气分布北海盆地

New insights into the origin of the bimodal volcanism in the middle Okinawa Trough： not a basalt-rhyolite differentiation process

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Frontiers of Earth Science 2018年第2期12卷 325-338页

作者： Yuxiang zhang zhigang zeng Shuai CHEN Xiaoyuan WANG Xuebo YIN Seafloor Hydrothermal Activity laboratory of the key laboratory of marine geology and environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China laboratory for marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China University of chinese academy of sciences Beijing 100049 China

In the middle Okinawa Trough （MOT）,rhyolites have been typically considered as products ofcrystallization differentiation of basaltic magma as afeature of bimodal volcanism. However, the evidence isinsufficient. This paper compared chemical trends ofvolcanic rocks from the MOT with fractional crystal-lization simulation models and experimental results andutilized trace element modeling combined with Rayleighfractionation calculations to re-examine fractional crystal-lization processes in generating rhyolites. Both qualitativeand quantitative studies indicate that andesites, rather thanrhyolites, originate by fractional crystallization frombasalts in the MOT. Furthermore, we established twobatch-melting models for the MOT rhyolites and proposedthat type 1 rhyolites are produced by remelting of andesiteswith amphiboles in the residue, while type 2 rhyolites arederived from remelting of andesites without residualamphiboles. It is difficult to produce melts with a SiO2content ranging from 62% to 68% either by magmaticdifferentiation from basalts or by remelting of andesites,and this difficulty might help account for the compositionalgap （Daly gap） for bimodal volcanism in the OkinawaTrough.

关键词： Okinawa Trough rhyolite andesite remelting fractional crystallization