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Journal of Ocean University of China 2016年第1期15卷 83-92页

作者： XU Zhenhuan LIU Ying LI Yuguo key laboratory of submarine geosciences and Prospecting Techniques of Ministry of Education Ocean University of China

Simulation and interpretation of marine controlled-source electromagnetic(CSEM) data often approximate the transmitter source as an ideal horizontal electric dipole(HED) and assume that the receivers are located on a flat ***,however,the transmitter dipole source will be rotated,tilted and deviated from the survey profile due to ocean *** free-fall receivers may be also rotated to some arbitrary horizontal orientation and located on sloping *** this paper,we investigate the effects of uncertainties in the transmitter tilt,transmitter rotation and transmitter deviation from the survey profile as well as in the receiver's location and orientation on marine CSEM *** model study shows that the uncertainties of all position and orientation parameters of both the transmitter and receivers can propagate into observed data uncertainties,but to a different *** interpreting marine data,field data uncertainties caused by the position and orientation uncertainties of both the transmitter and receivers need to be taken into account.

关键词： electromagnetic uncertainty in position and orientations data certainty marine CSEM

Inversion and Prediction of Consolidation Settlement Characteristics of the Fluvial Sediments Based on Void Ratio Variation in the Northern Modern Yellow River Subaqueous Delta, China

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Journal of Ocean University of China 2018年第3期17卷 545-554页

作者： LIU Xiao LIU Jie FENG Xiuli College of Environmental Science and Engineering Ocean University of China laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology key laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographySOA key laboratory of submarine geosciences and Prospecting Techniques of Ministry of Education Ocean University of China

The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacted and consolidate under the geostatic stress and overburden stress. It is one of the key areas with land subsidence disasters in China, bringing a series of safety hazards to production and living. Based on the data of massive surface cores and ten drill holes ranging from 12 to 40 m obtained from the northern modern Yellow River subaqueous delta, the inversion method suitable for the calculation of consolidation settlement characteristics of the modern Yellow River subaqueous delta is discussed, and the consolidation settlement characteristics of the delta sediments are inversed and predicted in this paper. The actual void ratio of the delta sediments at the depth from 3 to 15 m shows a significant power function relationship with the depth, while the void ratio of the sediments below 15 m changes little with depth. The pre-consolidation settlement(from deposition to sampling) of the delta sediments is between 0.91 and 1.96 m, while the consolidation settlement of unit depth is between 9.6 and 14.0 cm m^(-1). The post-consolidation settlement(from sampling to stable) of the subaqueous delta sediments is between 0.65 and 1.56 m in the later stage, and the consolidation settlement of unit depth is between 7.6 and 13.1 cm m^(-1) under the overburden stress. The delta sediments with a buried depth of 3 to 7 m contribute the most to the possible consolidation settlement in the later stage.

关键词： consolidation settlement void ratio sediment grain size northern modern Yellow River subaqueous delta

Petrology and geochemistry of cold seep carbonates from the northern Okinawa Trough,East China Sea:implications to early diagenesis

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Journal of Oceanology and Limnology 2022年第4期40卷 1388-1403页

作者： Kehong YANG Zhimin ZHU Yanhui DONG Weiyan ZHANG Fengyou CHU key laboratory of submarine geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

Carbonate samples were collected from the northern Okinawa Trough in the East China Sea in *** petrology,mineralogy,carbon and oxygen isotopes,and rare earth elements(REEs)of these samples were ***,high-Mg calcite,and dolomite were the main carbonate minerals,the contents of which varied greatly among the carbonate *** observations revealed the common occurrence of framboidal ***δ^(13)C values of carbonates varied from-53.7‰to-39.3‰(average of-47.3‰based on Vienna Pee Dee Belemnite(V-PDB),n=9),and theδ^(18)O values ranged from 0.6‰to 3.4‰(average of 1.9‰;V-PDB,n=9).The carbon and oxygen isotope characteristics indicated that the carbonates precipitated during the anaerobic oxidation of *** carbon source was a mixture of thermogenic methane and biogenic methane,possibly with a greater contribution from the *** oxygen isotope data showed that gas hydrate dissociation occurred during carbonate *** Ce anomalies suggested that the carbonates precipitated in an anoxic environment.A slight enrichment of middle REEs(MREEs)could be attributable to the early *** structures,minerals,oxygen isotopes,and MREEs all indicated that the carbonates experienced some degree of early ***,the infl uence of early diagenesis should be considered when using geological and geochemical proxies to reconstruct original methane seepage environments.

关键词： authigenic carbonate carbon and oxygen isotopes rare earth elements(REEs) anaerobic oxidation of methane(AOM) northern Okinawa Trough

Estimation of annual variation of water vapor in the Arctic Ocean between 80°–87°N using shipborne GPS data based on kinematic precise point positioning

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Acta Oceanologica Sinica 2015年第6期34卷 1-4页

作者： LUO Xiaowen ZHANG Tao GAO Jinyao YANG Chunguo WU Zaocai The Second Institute of Oceanography State Oceanic Administration key laboratory of submarine geosciences State Oceanic Administration

The measurement of atmospheric water vapor （WV） content and variability is important for meteorological and climatological research. A technique for the remote sensing of atmospheric WV content using ground-based Global Positioning System （GPS） has become available, which can routinely achieve accuracies for integrated WV content of 1-2 kg/m2. Some experimental work has shown that the accuracy of WV measurements from a moving platform is comparable to that of （static） land-based receivers. Extending this technique into the marine environment on a moving platform would be greatly beneficial for many aspects of meteorological research, such as the calibration of satellite data, investigation of the air-sea interface, as well as forecasting and climatological studies. In this study, kinematic precise point positioning has been developed to investigate WV in the Arctic Ocean （80°-87°N） and annual variations are obtained for 2008 and 2012 that are identical to those related to the enhanced greenhouse effect.

关键词： annual variation estimation water vapor Arctic Ocean kinematic precise point positioning

Geochemical Features of Sulfides from the Deyin-1 Hydrothermal Field at the Southern Mid-Atlantic Ridge near 15?S

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Journal of Ocean University of China 2017年第6期16卷 1043-1054页

作者： WANG Shujie LI Huaiming ZHAI Shikui YU Zenghui CAI Zongwei key laboratory of submarine geosciences and Prospecting Techniques Ministry of EducationCollege of Marine Geosciences Ocean University of China Qingdao 266100 P. R. China key laboratory of submarine geosciences Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012 P. R. China

In this study, geochemical compositions of elements in sulfide samples collected from the Deyin-1 hydrothermal field near the 15?S southern Mid-Atlantic Ridge(SMAR) were analyzed by the X-ray fluorescence spectrometry(XRF) and inductively coupled plasma mass spectrometry(ICP-MS) to examine the enrichment regulations of ore-forming elements and hydrothermal mineralization. These sulfide precipitates can be classified macroscopically into three types: Fe-rich sulfide, Fe-Cu-rich sulfide and Fe-Zn-rich sulfide, and are characterized by the enrichment of base metal elements along with a sequence of Fe>Zn>Cu. Compared with sulfides from other hydrothermal fields on MAR, Zn concentrations of sulfides in the research area are significantly high, while Cu concentrations are relatively low. For all major, trace or rare-earth elements(REE), their concentrations and related characteristic parameters exhibit significant variations(up to one or two orders of magnitude), which indicates the sulfides from different hydrothermal vents or even a same station were formed at different stages of hydrothermal mineralization, and suggests the variations of chemical compositions of the hydrothermal fluid with respect to time. The hydrothermal temperatures of sulfides precipitation decreased gradually from station TVG10(***10) to ***12, and to ***11, indicating that the precipitation of hydrothermal sulfides is subjected to conditions changed from high temperature to low temperature, and that the hydrothermal activity of study area was at the late stage of a general trend of evolution from strong to weak. The abnormally low concentrations of REE in sulfides and their similar chondrite-normalized REE patterns show that REEs in all sulfides were derived from a same source, but underwent different processes of migration or enrichment, or sulfides were formed at different stages of hydrothermal mineralization. The sulfides collected from the active hydrothermal vent were mainly attrib

关键词： southern Mid-Atlantic Ridge Deyin-1 hydrothermal field hydrothermal sulfide geochemistry of element mineralization

Geochronology, Geochemistry and Its Tectonic Significance of Chahe Granites in Hainan Island

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Journal of Earth Science 2013年第4期24卷 619-625页

作者：唐立梅陈汉林董传万初凤友 key laboratory of submarine geosciences Second Institute of OceanographyState Oceanic Administration Department of Earth Sciences Zhejiang University

There are very few studies on the granites formed in Late Permian in Hainan （海南） Island. Petrology, geochronology and geochemistry research on Late Permian granites in Chahe （叉河） area, Hainan Island will be reported in this article. The results show that, Chahe granites formed in 251 Ma, are riched in SiO2, alkali, Fe203 while depleted in MgO and CaO, with low Sr and high Yb, and have all the features consistent with A-type granite. The forming of Chahe granites may suggest that Hainan Island was already in post-orogenic setting in Late Permian.

关键词： granite U-Pb age dating geochemistry Hainan Island.

Application of Seismic Interferometric Migration for Shallow Seismic High Precision Data Processing: A Case Study in the Shenhu Area

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Journal of Ocean University of China 2018年第1期17卷 46-52页

作者： WEI Jia LIU Huaishan XING Lei DU Dong key laboratory of submarine geosciences and Exploration Techniques Ministry of Education Ocean University of China Tianjin Center ChinaGeological Survey

The stability of submarine geological structures has a crucial influence on the construction of offshore engineering projects and the exploitation of seabed resources. Marine geologists should possess a detailed understanding of common submarine geological hazards. Current marine seismic exploration methods are based on the most effective detection technologies. Therefore, current research focuses on improving the resolution and precision of shallow stratum structure detection methods. In this article, the feasibility of shallow seismic structure imaging is assessed by building a complex model, and differences between the seismic interferometry imaging method and the traditional imaging method are discussed. The imaging effect of the model is better for shallow layers than for deep layers because coherent noise produced by this method can result in an unsatisfactory imaging effect for deep layers. The seismic interference method has certain advantages for geological structural imaging of shallow submarine strata, which indicates continuous horizontal events, a high resolution, a clear fault, and an obvious structure boundary. The effects of the actual data applied to the Shenhu area can fully illustrate the advantages of the method. Thus, this method has the potential to provide new insights for shallow submarine strata imaging in the area.

关键词： seismic interferometric migration shallow strata Shenhu area migration imaging

New Zircon U-Pb Age of Late Devonian Tuff in Guangxi, South China and the Significance for the Paleo-Tethys Branch Ocean

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 402-403页

作者： HU Lisha DU Yuansheng XU Yajun WANG Zhiwen WANG Chenghao Collage of Marine geosciences Key Laboratory of Submarine Geosciences and Prospecting Technology Ocean University of China laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology (QNLM) State key laboratory of Biogeology and Environmental Geology China University of Geosciences

Objective The eastern extending range of the Paleo-Tethys Ocean in southwest China has always been focused and controversial. At the beginning of this century some scholars proposed that the Paleo-Tethys Branch Ocean may extend to the Babu-Pingxiang and Cengxi areas along the stouthwestern margin of the South China Block （Cai and Zhang, 2009）. However, the pivotal proof of Late Paleozoic ophoilite and magmatic rocks was absent or sporadical in the Guangxi Zhuang Autonomous Region, resulting in insufficient evidence to support this viewpoint. For the first time this work reported the Late Devonian tuff in the Qinzhou area in the south of the Guangxi Zhuang Autonomous Region and conducted zircon U-Pb dating on it in order to constrain the extension of the Paleo-Tethys Ocean in the South China Block.

关键词： the Paleo-Tethys Branch Ocean New Zircon U-Pb Age of Late Devonian

Sustained growth of the largest uninhabited alluvial island in the Changjiang Estuary under the drastic reduction of river discharged sediment

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Science China Earth Sciences 2021年第10期64卷 1687-1697页

作者： Xiaodong ZHANG Rui XIE Daidu FAN Zuosheng YANG Hongmin WANG Chuang WU Yuhan YAO key Lab of submarine geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China State key laboratory of Marine Geology Tongji UniversityShanghai 200092China

The evolution of the Changjiang Delta is obviously affected by current rapidly rising sea level and drastically declining river discharge,and it is also vital for the sustainable development of Shanghai and the Changjiang River Economic Belt,which represent China’s economic development leader and major national strategic area,*** this paper,the growth pattern of Jiuduansha Island,the largest uninhabited alluvial island in the Changjiang Estuary,is studied in terms of the change in elevation,position and area over the past 50 years through using satellite-derived instantaneous shoreline positions and high/low tide exposure areas based on 497 satellite images from 1974 to 2020;and the influencing factors and future development patterns are further discussed by comparison with other alluvial islands or sandbars in the *** results show that Jiuduansha Island has maintained a rapid or even accelerated area growth rate,although the sediment discharge of the Changjiang River has sharply decreased in recent *** sustained growth is mainly attributed to the existence of the estuarine turbidity maximum zone,coarsening fluvial sediment,onshore sediment replenishment by tide,cone-like geomorphology of Jiuduansha Island,and siltation promotion effect of *** growth rate of the low tide exposure area of Jiuduansha Island increased from 1.9 km^(2)a^(−1) in 1974–1990 to 3.0 km^(2)a^(−1) in 1990–2020,and the growth rate of the high tide exposure area reached as high as 3.7 km^(2)a^(−1) in 1994–*** implementation of the Deep-Water Channel Project has significantly affected the evolution of Jiuduansha Island,including shifting the heads of Shangsha and Zhongxiasha from severe retreat to rapid accretion,and promoting tidal flat progradation seaward of the Jiangyanansha and Zhongxiasha,but restricting the growth of the low tide exposure area of Jiuduansha Island.

关键词： Delta evolution Changjiang Estuary Jiuduansha Island Sandbar and sand island Satellite image

The composition and origination of particles from surface water in the Chukchi Sea, Arctic Ocean

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Advances in Polar Science 2014年第3期25卷 147-154页

作者： YU Xiaoguo LEI Jijiang YAO Xuying ZHU Jihao JIN Xiaobing key laboratory of submarine geosciences Second Institute of Oceanography SOA

Suspended particle samples were collected at 11 stations on the shelf and slope regions of the Chukchi Sea and the central Arctic Ocean during the fifth Chinese National Arctic Research Expedition （summer 2012）. The particle concentration, total organic carbon （TOC）, total nitrogen （TN） and the isotopic composition of the samples were analyzed. The suspended particle concentration varied between 0.56 and 4.01 ***; the samples collected from the sea ice margin have higher concentrations. The organic matter content is higher in the shelf area （TOC： 9.78%-20.24%; TN： 0.91‰-2.31%）, and exhibits heavier isotopic compositions （δ13C： -23.29‰ to -26.33‰ PDB; δ15N： 6.14‰-7.78‰）, indicating that the organic matter is mostly marine in origin with some terrigenous input. In the slope and the central Arctic Ocean, the organic matter content is lower （TOC： 8.06%- 8.96%; TN： 0.46%-0.72%）, except for one sample （SR15）, and has lighter isotopic compositions （δ13C： -26.93‰ to -27.78‰ PDB; δ15N： 4.13‰-4.84‰）. This indicates that the organic matter is mostly terrestrially-derived in these regions. The extremely high amount of terrigenous organic matter （TOC： 27.94%; TN： 1.16%; δ13C： -27.43‰ PDB; δ15N： 3.81‰） implies that it was carried by transpolar currents from the East Siberian Sea. Material, including sea ice algae, carried by sea ice are the primary source for particles in the sea ice margins. Sea ice melting released a substantial amount of biomass into the shelf, but a large amount of detrital and clay minerals in the slope and the central Arctic Ocean.

关键词： Chukchi Sea particles organic matter stable isotopes