检索结果-南通市图书馆

Evolution model of a modern delta fed by a seasonal river in Daihai Lake,North China:determined from groundpenetrating radar and trenches

引用

Frontiers of Earth Science 2019年第2期13卷 262-276页

作者： Beibei LIU Chengpeng TAN Xinghe YU Xin SHAN Shunli LI College of Geosciences China University of PetroleumBeijing 102249China School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Key Laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographyState Oceanic AdministrationQingdao 266061China School of Energy Resources China University of Geosciences (Beijing)Beijing 100083China

While deltas fed by seasonal rivers are common in modem sedimentary environments,their characteristics remain unclear as compared to those fed by perennial *** study identifies a small delta discharged by a seasonal stream flowing into Daihai Lake,in northern China,which is driven by ephemeral and high-energy flood *** 3D facies architecture was analyzed using ground-penetrating radar (GPR) and sedimentary logs from outcrop and *** types of radar surfaces,including truncations of underlying inclined strata,weak reflections,and depositional surface of downlap and onlap,were *** radar facies (highangle obliquetangential,low-angle subparallel,gently plane parallel,plane-parallel,chaotic,and continuous strong reflection) were identified based on distinctive reflections,including amplitude,continuity,dip,and termination *** depositional units (Unit A to E) were documented from proximal to distal *** discharge signatures include significant grain-size decrease over short distance,abundant Froude supercritical flow sedimentary structures,poorly developed barforms,and small-scale scour and fill *** of lake-level and sediment budget were evaluated over the past 60 *** highstand stage (1960- 1980),amalgamated channel (Units A and B),and delta front (Unit C) were *** slope stage (1980-1996),the lower deposits (Units A,B,C) were eroded by Unit D with a distinct truncation *** lowstand stage,most eroded sediments bypassed the incised channel and accumulated in the distal part,in which a new depositional unit was formed (Unit E).The model demonstrates that deltas fed by seasonal rivers tend to accumulate large amounts of sediments carried by high magnitude floods within short periods.

关键词： delta evolution seasonal discharge ground-penetrating radar sedimentary architecture Daihai Lake

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geotechnical properties and stability of the submarine canyon in the northern South China Sea

引用

Acta Oceanologica Sinica 2019年第11期38卷 91-98页

作者： Jie Liu Lejun Liu Ping Li Shan Gao Wei Gao Yuanqin Xu Key Laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Marine Engineering Environment&Geomatic Center First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China

The upper part of the continental slope in the northern South China Sea is prone to submarine landslide disasters,especially in submarine *** work studies borehole sediments,discusses geotechnical properties of sediments,and evaluates sediment stability in the study *** results show that sediment shear strength increases with increasing depth,with good linear *** in shear strength of sediments with burial depth have a significantly greater rate of change in the canyon head and middle part than those in the canyon *** sediments at the same burial depth,shear strength gradually increased and then decreased from the head to the bottom of the canyon,and has no obvious correlation with the slope angle of the sampling *** static conditions,the critical equilibrium slope angle of the sediments in the middle part of the canyon is 10°to 12°,and the critical slope angle in the head and the bottom of the canyon is 7°.The results indicate that potential landslide hazard areas are mainly distributed in distinct spots or narrow strips on the canyon walls where there are high slope angles.

关键词： shear strength slope stability analysis submarine canyons northern South China Sea

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Holocene tephra deposits in the northern Okinawa Trough

引用

Acta Oceanologica Sinica 2006年第1期25卷 78-89页

作者： LIU Yanguang OLE BjФrslev Nielsen ZHANG Deyu DU Dewen JAN Heinemeier WU Yonghua College of Marine Geosciences Ocean University of China Qingdao 266003 China Key Laboratory of Marine sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Department of Earth Sciences University ofAarhus Aarhus C DK-8000 Denmark AMS 14C Laboratory University ofAarhus Aarhus C DK-8000 Denmark

The mineralogical and geochemical characteristics of sediments of Core CSH1, which was collected from the northern Okinawa Trough, indicate that large amounts of volcanic materials have deposited in the northern Okinawa Trough during the Holocene. On the basis of down-core variations in mineral and element contents of sediments, two layers in the uppermost section of Core CSH 1 characterized by high quartz, Na2O, MnO, K20, uranium contents and low contents of clay minerals, volatiles, Fe2O3, MgO, CaO and strontium, have been identified as the tephra deposits. Systematic grain-size measurements also suggest that sediments from the northern Okinawa Trough are made up of terrigenous materials and volcanic ashes with different proportion during the Holocene. The sedi- ments of tephra layers in Core CSH1 show bi-modal patterns in grain-size distribution with modal grain-sizes of 74.3 and 7.81 μm, respectively. According to the radiocarbon dating on shells of zooplankton foraminifera, two tephra layers in Core CSH1, formed at 7 250 and 10 870 a BP （cal）, approximately correspond to the K-Ah tephra [7 300 a BP （cal）] and the eruption of Kuju Volcano （12-10 ka BP）, respectively.

关键词： Okinawa Trough Holocene tephra deposits

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Os isotope dating and growth hiatuses of Co-rich crust from central Pacific

引用

Science China Earth Sciences 2008年第10期51卷 1452-1459页

作者： LI JiangShan FANG NianQiao QU WenJun DING Xuan GAO LianFeng WU ChangHang ZHANG ZhenGuo School of Marine China University of GeosciencesBeijing 100083China Key Laboratory of Marine sedimentology and Environmental Geology of State Oceanic Administration First Institute of Oceanog-raphyState Oceanic AdministrationQingdao 266061China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China National Research Centre for Geoanalysis Beijing 100037China Hebei Polytechnic University Tangshan 063009China

Up to now, accurate determination of the growth age and hiatuses of the Co-rich crust is still a difficult work, which constrains the researches on the genesis, growth process, controlling factors, regional tectonics, paleo-oceanographic background, etc. of the Co-rich crust. This paper describes our work in determining the initial growth age of the Co-rich crust to be of the late Cretaceous Campanian Stage (about 75-80 Ma), by selecting the Co-rich crust with clear multi-layer structures in a central Pacific seamount for layer-by-layer sample analysis and using a number of chronological methods, such as Co flux dating, dating by correlation with 187Os/188Os evolution curves of seawater, and stratigraphic divi- sion by calcareous nannofossils. We have also discovered growth hiatuses with different time intervals in the early Paleocene, middle Eocene, late Eocene and early-middle Miocene, respectively. These re- sults have provided an important age background for further researches on the Co-rich crust growth process and the paleo-oceanographic environment evolution thereby revealed in the said region.

关键词： central Pacific Co-rich crust Os isotope dating growth hiatus

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Growth ages of ferromanganese crusts from the western and central Pacific:Comparison between nannofossil analysis and ^(10)Be dating

引用

Chinese Science Bulletin 2006年第24期51卷 3035-3040页

作者： CHENG Zhenbo SHI Xuefa WU Yonghua SU Xin LI Xiaoyan WANG Kunshan YANG Yongliang GE Shulan JU Xiaohua SHI Fengdeng M. Hiroyuki Key Laboratory of Marine sedimentology and Environmental Geology State Oceanic Administration Qingdao 266061 China Key Laboratory of Lithospheric Tectonic Deep-Level Process China National Research Center for Geoanalysis Chinese Academy of Geological Sciences Beijing 100037 China Micro Analysis Laboratory Tandem Accelerator University of Tokyo Tokyo 113-0032 Japan

Based on results of nannofossil analysis and 10Be dating in ferromanganese crusts M1-1 and A1-1 (no nannofossils were found in it),from the western and central Pacific respectively,it is found that the crust growth ages from nannofossil biostrati-graphy agree well with those based on 10Be isotope analysis. Both crusts have three growth layers,and the oldest layer was deposited in Miocene at about 12.80 Ma. The maximum,minimum,and average growth rates of crust A1-1 (from the central Pacific) are 8.11,1.92 and 3.47 mm/Ma,and those of crust M1-1 (from the western Pacific) are 2.93,0.47,and 0.94 mm/Ma.

关键词：太平洋中西部铁锰结壳微化石分析生长年代 10Be测年

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sediment consolidation settlement of Chengbei Sea area in the northern Huanghe River subaqueous delta,China

引用

Chinese Journal of Oceanology and Limnology 2017年第3期35卷 693-703页

作者：刘杰冯秀丽刘潇 Key Laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographyState Oceanic Administration(SOA)Qingdao 266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Key Lab of Submarine Geosciences and Prospecting Techniques Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

One of the most important factors controlling the morphology of the modem Huanghe （Yellow） River delta is consolidation settlement, which is impacted by fast deposition, high water content, and low density of seafloor sediment. Consolidation settlement of the Huanghe River subaqueous delta was studied based on field data, laboratory experiments on 12 drill holes, and the one-dimensional consolidation theory. Results show that vertical sediment characteristics varied greatly in the rapidly forming sedimentary bodies of the modem Huanghe River subaqueous delta. Sediments in the upper parts of drill holes were coarser than those in the deeper parts, and other physical and mechanical properties changed accordingly. On the basis of the one-dimensional consolidation theory and drilling depth, the final consolidation settlement of drill holes was between 0.6 m and 2.8 m, and the mean settlement of unit depth was at 1.5-3.5 cm/m. It takes about 15-20 years for the consolidation degree to reach 90% and the average sedimentation rate within the overlying 50 m strata was at 5 cm/a to 12 cm/a. This study helps to forecast the final consolidation settlement and settlement rate of the modem Huanghe River subaqueous delta, which provides key geotechnical information for marine engineers.

关键词： mechanical properties consolidation settlement drill hole modem Huanghe River subaqueous delta

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Petrology and geochemistry of South Mid-Atlantic Ridge(19°S) lava flows:Implications for magmatic processes and possible plume-ridge interactions

引用

Geoscience Frontiers 2020年第6期11卷 1953-1973页

作者： Haitao Zhang Xuefa Shi Chuanshun Li Quanshu Yan Yaomin Yang Zhiwei Zhu Hui Zhang Sai Wang Yili Guan Renjie Zhao Key Laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural and ResourcesQingdaoShandong266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong266061China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China National Deep Sea Center Ministry of Natural and ResourcesQingdao266061China

The South Mid-Atlantic Ridge(SMAR)19°S segment,approximately located along the line of Saint Helena volcanic chain(created by Saint Helena mantle plume),is an ideal place to investigate the issue whether the ridgehotpot interaction process affected the whole *** this study,we present major and trace elemental compositions and Sr-Nd-Pb isotopic ratios of twenty fresh lava samples concentrated in a relatively small area in the SMAR 19°S *** oxides compositions show that all samples are *** contents of compatible trace elements(e.g.,Ni=239-594 ppm and Cr=456-1010 ppm)and low Fe/Mn(54-67)and Ce/Yb(0.65-1.5)ratios of these lavas show that their parental magmas are partially melted by a spinel lherzolite mantle *** software PRIMELT3,this study obtained mantle potential temperatures(Tp)beneath the segment of1321-1348℃,which is lower relative to those ridges influenced by mantle *** asthenospheric mantle beneath the SMAR 19°S segment starts melting at a depth of^63 km and ceases melting at^43 km with a final melting temperature of^1265℃.The extent of partial melting is up to 16%-17.6%with an average adiabatic decompression value of 2.6%/*** correlations of major oxides(CaO/Al2 O3)and trace elements(Cr,Co,V)with MgO and Zr show that the parental magma experienced olivine and plagioclase fractional crystallization during its ascent to the surface.87Sr/86Sr(0.702398-0.702996),143 Nd/144 Nd(0.513017-0.513177)and 206Pb/204Pb(18.444-19.477)ratios of these lavas indicate the mantle source beneath the SMAR 19°S segment is composed of a three-component mixture of depleted MORB mantle,PREMA mantle,and HIMU mantle *** simple,binary mixing results among components from plume-free SMAR MORB,Saint Helena plume and Tristan plume show that asthenospheric mantle beneath the SMAR 19°S segment may be polluted by both Saint Helena and Tristan plume enriched *** abovementioned mantle potential temperatures,together with the low Sai

关键词： Magmatic process Mantle potential temperature Crystallization pressure Plume-ridge interaction South Mid-Atlantic Ridge

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Orbital cyclicity in sedimentary sequence and climatic indications of C-O isotopes from Lower Cretaceous in Qingxi Sag, Jiuquan Basin, NW China

引用

Geoscience Frontiers 2019年第2期10卷 467-479页

作者： Siding Jin Haiyang Cao Hua Wang Michael Wagreich Sylvain Richoz State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology College of Energy Resources Chengdu University of Technology Institute of Sedimentary Geology Center for Post-doctoral StudiesChengdu University of Technology Key Laboratory of Tectonics and Petroleum Resources China University of Geosciences Department of Geodynamics and sedimentology University of Vienna Institute of Earth Sciences NAWI GrazUniversity of Graz

Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag, Jiuquan Basin(NW China). Zircon U-Pb ages of the dated basalts at the top of the Xiagou Formation give an isochron age of 115.6 Ma, and the sedimentation interval of the Xiagou Formation was speculated to range from about 125/124 Ma to 115 Ma based on paleontological research and stratigraphic correlation analysis. Here we use GR logging data as a palaeoenvironmental and palaeoclimatic proxy to conduct a detailed cyclostratigraphic study of five selected wells. Power spectra, evolutionary fast Fourier transformation and wavelet analysis all reveal significant sedimentary cycles in the Xiagou Formation. The ratios of cycle wavelengths in these stratigraphic units are 33.82 m : 7.91 m : 3.06 m : 1.79 m, which is similar to the ratio of orbital targets of 20 : 5 : 2 : 1. The ratio of 20 : 5 : 2 : 1 is interpreted as Milankovitch cycles of 405 kyr long eccentricity,100 kyr short eccentricity, 37 kyr obliquity, and 22 kyr precession cycles respectively. A high-resolution astronomical time scale is constructed by tuning the stratigraphy into target curves of orbital cycles respectively. Based on the astronomical time scale, the absolute ages of 55 samples were estimated,which are used for subsequent stable carbon and oxygen isotope stratigraphy analysis. The analysis results of the five studied wells in the Qingxi Sag indicate:(1) a negative trend of δ^(13)C values upwards in the Xiagou Formation, and(2) negative δ^(18)O values with a positive trend upwards. Both relatively heavy values and pronounced covariances of δ^(13)C values and δ^(18)O values indicate an arid-evaporationcontrolled climate during the sedimentary period of the Lower Cretaceous Xiagou Formation, Qingxi Sag, Jiuquan Basin. Moreover, positive covariances of SQK_1g_(2+3) indicate extremely high temperature, and negative covariances of SQK_1g_1 indicate a relatively l

关键词： Jiuquan Basin Qingxi Sag Xiagou Formation Orbital cyclicity Stable isotope

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Eogenetic Karst in Interbedded Carbonates and Evaporites and Its Impact on Hydrocarbon Reservoir: A New Case from Middle Triassic Leikoupo Formation in Sichuan Basin, Southwest China

引用

Journal of Earth Science 2019年第5期30卷 908-923页

作者： Hong Liu Xiucheng Tan Ling Li Xiong Ding Jian Cao Guang Yang Teng Ma State Key Laboratory of Oil and Gas Geology and Exploitation Southwest Petroleum University Chengdu 610500 China School of Earth Sciences and Technology Branch of Sedimentology and Hydrocarbon Accumulation CNPC Key Laboratory of Carbonate Reservoir Southwest Petroleum University Chengdu 610500 China Department of Earth Sciences Nanjing University Nanjing 210023 China Institute of Petroleum Exploration and Exploitation PetroChina Southwest Oil and Gas Field Company Chengdu 610051 China

Karst in interbedded carbonates and evaporites has been reported to have important and complex impacts on reservoir. It is significant for exploration and karst geology. Here, we report such a new case from Middle Triassic Leikoupo Formation of Sichuan Basin, Southwest China. Stratigraphic incompleteness and the occurrence of unconformity provide evidence for the presence of eogenetic karst. Under the impact of this eogenetic karst, residual weathered and solution-collapse breccia, solution pores and silicification and dedolomitization have been observed. Classic stratigraphic zonation of karst is not readily distinguishable, which is ascribed to the stratigraphic collapse of carbonate rocks resulting from the dissolution of evaporites by lateral subsurface fluid flow. In terms of impact on reservoir quality, karst can generally improve the initial physical property of the porous layers in theory. However, subsurface fluid flow dissolved the evarporitic beds and facilitated the collapse of overlying strata. As a consequence, the lateral continuity of the reservoirs would be destroyed, and relatively high-quality reservoirs can only be developed with little collapse of overlying strata, reflecting reservoir heterogeneities. This may be a general feature of reservoir formation under the impact of karst in interbedded carbonates and evaporites.

关键词： karst carbonate reservoir evaporite Middle Triassic Leikoupo Formation Sichuan Basin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Novel Approach for Inferring the Proportion of Terrestrial Organic Matter Input to Marine Sediments on the Basis of TOC:TN and δ<sup>13</sup>C<sub>org</sub>Signatures

引用

Open Journal of Marine Science 2013年第2期3卷 74-92页

作者： Antonio Fernando Menezes Freire Marcelo Costa Monteiro Department of Geochemistry Petrobras Research Center Rio de Janeiro Brazil Department of sedimentology and Stratigraphy Petrobras Research Center Rio de Janeiro Brazil

The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sediments. A plot of TOC:TN vs. δ13Corg is useful for such studies but is strongly based on qualitative constraints. This study is based on the qualitative characterization of the source of Quaternary OM via analysis of TOC:TN and δ13Corg signatures, but also proposes a probability parameter, which combines both signatures, to infer the amount of Terrestrial OM Input (TOMI). This index provides a method for quantifying the proportion of terrestrial OM vs. marine OMin a more comprehensive manner. The TOMI index concept was applied to a study area in theJoetsuBasin, eastern margin of theJapanSea, where previous studies have characterized theOMfrom the Last Glacial Maximum (LGM) to the present. The upwards increase in TOC indicates thatOMproduction during the Holocene was higher than during the LGM. The enriched δ13Corg signature upwards and decrease in TOC:TN suggest predominantly marine phytoplankton OM during the Holocene. Throughout the LGM, low OM production with depleted δ13Corg values and high TOC:TN values in the sediments suggest a predominantly C3 terrestrial plant source for the OM. Using these data, it was possible to calculate a proxy for a sea level variation curve during that period and to investigate the influence of the proximity of the coastal line to the continental slope on the input of terrestrial material to the basin. The proposal provides information for the application of sequence stratigraphic concepts. The TOMI index could confirm that the proximity to the shoreline and shelf break has a strong influence on the input of terrestrial material during lowstand periods.

关键词： δ13Corg Joetsu Basin Japan Sea Terrestrial Organic Matter Input TOMI Index TOC:TN

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：