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Submarine Trenches and Wave-Wave Interactions Enhance the Sediment Resuspension Induced by Internal Solitary Waves

Journal of Ocean University of China 2023年第4期22卷 983-992页

作者： TIAN Zhuangcai LIU Chao JIA Yonggang SONG Lei ZHANG Mingwei State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Key Laboratory of Coastal Science and Integrated Management Ministry of Natural ResourcesQingdao266061China

Internal solitary waves(ISWs)are nonlinear fluctuations in nature that could cause significant interactions between seawater and the seabed.ISWs have been proven to be an adequate cause of sediment resuspension in shallow and deep-sea environments.In the South China Sea,ISWs have the largest amplitude globally and directly interact with the seabed near the Dongsha slope in the northern South China Sea.We analyzed the water profile and high-resolution multibeam bathymetric data near the Dongsha slope and revealed that submarine trenches have a significant impact on the sediment resuspension by ISWs.Moreover,ISWs in the zone of the wave-wave interaction enhanced sediment mixing and resuspension.The concentration of the suspended particulate matter inside submarine trenches was significantly higher than that outside them.The concentration of the suspended particulate matter near the bottoms of trenches could be double that outside them and formed a vast bottom nepheloid layer.Trenches could increase the concentration of the suspended particulate matter in the entire water column,and a water column with a high concentration of the suspended particulate matter was formed above the trench.ISWs in the wave-wave interaction zone near Dongsha could induce twice the concentration of the bottom nepheloid layer than those in other areas.The sediment resuspension caused by ISWs is a widespread occurrence all around the world.The findings of this study can offer new insights into the influence of submarine trench and wave-wave interaction on sediment resuspension and help in geohazard assessment.

关键词： sediment resuspension internal solitary waves trench wave-wave interaction

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In-situ Observations of Engineering Geological Environment during Hydrate Production Tests in Deepwater

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 193-194页

作者： ZHU Chaoqi JIA Yonggang Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (Ocean University of China) Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology

Gas hydrates are ice-like combinations of methane and water.The global inventory of gas hydrates appears to be very large.Recent estimates of the total amount of methane contained in the world’s gas hydrates range

关键词： estimates contained inventory methane hydrate mankind recovered fossil resistivity Siberia

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Experimental Researches on the Accuracy of Micro- Electromechanical Accelerometer-Array in Seafloor Failure Deformation Measurement

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Journal of Ocean University of China 2022年第5期21卷 1198-1204页

作者： WANG Zhenhao LIU Xiaolei ZHANG Shaotong WEN Mingzheng SHAN Hongxian JIA Yonggang First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Tianjin Center China Geological SurveyTianjin 300170China

At present,there are few technologies applied to in situ observation of seabed deformation,among which the micro-electromechanical accelerometer-array(hereinafter referred to as accelerometers array)is a very advantageous measurement method,with both commercial products and successful application cases.However,the coupling effect between accelerometer-array and sur-rounding soil and the linkage effect of accelerometer-array itself during the deformation may influence the accuracy and reliability of the measurement data.A simulation test chamber was designed and processed,and four groups of simulation tests were carried out to explore the coupling effect and linkage effect of accelerometer-array in the soil with different degree of consolidation.The results show that the accelerometer-array and the soil coupled well,and the coupling effect is positively correlated with the degree of soil consoli-dation.The ratio of accumulative deviation to soil lateral deformation is high at the initial stage of deformation(0-50 mm)and reduced with the continuous increase of deformation(>100 mm).In the process of liquefied soil deformation,the linkage effect of accelerometer array can be ignored,and is negatively correlated with the degree of soil consolidation.A concept to improve the measurement accu-racy of accelerometer-array in different seafloor failure deformation modes is proposed.The research results provide references for the modification of accelerometer-array and the improvement for other flexible rod-shaped deformation sensors.

关键词： micro-electromechanical accelerometer-array seafloor failure deformation in situ observation coupling effect linkage effect

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The profile of sound speed and dissolved oxygen in the polymetallic nodules depositional area in the Western Pacific

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Journal of Oceanology and Limnology 2023年第6期41卷 2090-2100页

作者： Bowen LI yonggang jia Zhihan FAN Kai LI College of Oceanography and Space Information China University of PetroleumQingdao 266580China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China

With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodule mining cannot be ignored.However,duo to the lacks in stable and safe deep-sea(the depth>1000 m)vertical profile observation systems and consequently in long-term in-situ observation data,the sound speed and dissolved oxygen and the other water environment factors in the deposition areas of polymetallic nodules remains poorly understood.In this study,a deep-sea in-situ observation system was designed and deployed,and the water environment data of the polymetallic nodule deposition area were collected and analyzed.Result shows that the dissolved oxygen in the depth of 0–600 m was mainly affected by biological factors,while that in the area deeper than 600 m was affected by physical factors.The sound speed in the water body was mainly affected by temperature and pressure.At depths below 840 m,the sound speed is mainly controlled by temperature,and at depths between 840 m and 5700 m,the sound speed is mainly controlled by pressure.The correlations of sound speed vs.pressure and vs.temperature were regressed into equation.The resuspension of sediments rich in various metals may result in the reduction of dissolved oxygen and the improvement of redox potential.This environmental impact caused by a single sediment resuspension could last for 24 h or more.These findings enrich the understanding of the background value of the water environment in the polymetallic nodule deposition area.

关键词： deep sea dissolved oxygen redox potential sound speed conductivity

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Marine Geohazards： Review and Future Perspective

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1455-1470页

作者： JIA Yonggang ZHU Chaoqi LIU Liping WANG Dong Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (Ocean University of China) Qingdao Shandong 266100 China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Qingdao Shandong 266061 China Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao Shandong 266100 China

With offshore resource exploration moving to the deep water, marine geohazards have been attracting attention from the academic and industry. Research achievements of marine geohazards were reviewed in this paper. We analyzed and discussed typical issues among marine geohazards, including coastal erosion, submarine slope failure, turbidity current and special hazards induced by gas hydrate dissociation, in terms of their definition, distribution, characteristics and case studies. Major international projects on marine geohazards headed by the United States, Europe, Japan and other international organizations are introduced as well. Three marine geohazard survey methods, including geophysical survey, geotechnical exploration and in-situ observation, were summarized with a brief description of each approach, respectively. Especially, the history of marine geohazard researches in China is briefly reviewed, showing the disparity between China and developed countries in the study of marine geohazards narrows gradually. The potential research tendency in future was suggested.

关键词： marine geohazards submarine landslide gas hydrate coastal erosion in-situ observation

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Occurrence of Different Forms and Implications of Compound Specific Sterols in Continental Sediments of the Northeast South China Sea

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 420-429页

作者： QIU Hong ZOU Li ZHANG Minsheng ZHU Chaoqi JIA Yonggang College of Environmental Science and Engineering Ocean University of China Education Key Laboratory fo r Marine Environment and Ecology Ocean University of China The Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China

The South China Sea(SCS) is one of the most productive and accumulative marginal shelves of organic carbon in the world. To expound the transformation and preservation of organic carbon in the Northeast SCS, where abundant oil and gas resources have been reported, compound specific sterols in free(FR), base hydrolytic(BH), and acid hydrolytic(AH) forms were analyzed in surface and columnar sediments in May, 2016. The results showed that the total contents of sterols detected ranged from 0.15 to 3.74 ppm dry weight in the surface sediments, and gradually decreased from 3.41 to0.17 ppm dry weight from surface to deep sediments, in which cholesterol(27^(△5)) was the most abundant component. Sterols mainly existed in the BH form(54.51%-74.20%), followed by the FR form(25.50%-45.49%) and then the AH form(0-3.77%) in turn, in the surface sediments. BH and FR sterols accounted for 0-49.08% and 50.92%-100% in the columnar sediments, while AH sterols were undetectable. The contents of specific sterols indicated that, the primary source of marine organic carbon was about 5 times as much as that from terrestrial input. More and more FR sterols transformed into BH sterols with increasing sedimentary depth, and BH sterols absolutely dominated in sediment depths under 25 cm. The forms of Sterols C27 were maintained at a relative consistence state, but Sterols C28 to C30 degraded gradually during the sedimentation process. It was suggested that the stability of sterols, based on the chemical structures, might be the primary factor controlling their degradation and preservation in deeper sediments. These results would help to understand the organic carbon(OC) transformation in a hydrate formation area in a marginal sea.

关键词： sterols sediments occurrence forms transformation northeast South China Sea

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Extension of Highly Efficient Alcohol-promoted Rearrangement into One-pot Domino Palladium-catalyzed Carbonylation for Sterically Crowded Aromatic Six-membered Imides

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Chemical Research in Chinese Universities 2023年第6期39卷 1106-1110页

作者： GUO Rong ZHANG Jingmei jia Xiaohui SHI Chunfeng QIE Fengxiang ZHEN yonggang Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029P.R.China State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSINOPECBeijing 100083P.R.China National Demonstration Center for Experimental Life Sciences&Biotechnology Education Beijing Normal University100875 BeijingP.R.China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074P.R.China State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275P.R.China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024P.R.China

Aromatic six-membered imides suffer the introduction of bulky substituents at the imide positions due to the formation of isoimides and low reactivity,preventing from the investigation of the intrinsic molecular properties.Here,we found a highly efficient alcohol-promoted rearrangement from isonaphthalimide to naphthalimide under acid or basic nonaqueous conditions,which can be regarded as model compounds for aromatic six-membered imides.We proposed two-step nucleophilic substitutions in the isomerization mechanistic pathways that were verified by the separation of a key intermediate.Furthermore,in-situ ^(1)H NMR exhibited the first-order kinetics for the isoimide loss process.Finally,the alcohol-promoted isoimide-imide rearrangement was extended to a palladium-catalyzed one-pot domino carbonylation reaction toward sterically crowded aromatic six-membered imides.

关键词： Bulky aromatic imide Imide isomerization Domino synthesis Organic semiconductor

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Deep seabed mining:Frontiers in engineering geology and environment

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International Journal of Coal Science & Technology 2023年第2期10卷 1-31页

作者： Xingsen Guo Ning Fan Yihan Liu Xiaolei Liu Zekun Wang Xiaotian Xie yonggang jia Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Department of Civil Environmentaland Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUK College of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province Wenzhou UniversityWenzhou 325035China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China

Ocean mining activities have been ongoing for nearly 70 years,making great contributions to industrialization.Given the increasing demand for energy,along with the restructuring of the energy supply catalyzed by efforts to achieve a low-carbon economy,deep seabed mining will play an important role in addressing energy-and resource-related problems in the future.However,deep seabed mining remains in the exploratory stage,with many challenges presented by the high-pressure,low-temperature,and complex geologic and hydrodynamic environments in deep-sea mining areas,which are inaccessible to human activities.Thus,considerable efforts are required to ensure sustainable,economic,reliable,and safe deep seabed mining.This study reviews the latest advances in marine engineering geology and the environment related to deep-sea min-ing activities,presents a bibliometric analysis of the development of ocean mineral resources since the 1950s,summarizes the development,theory,and issues related to techniques for the three stages of ocean mining(i.e.,exploration,extraction,and closure),and discusses the engineering geology environment,geological disasters,in-situ monitoring techniques,envi-ronmental protection requirements,and environmental effects in detail.Finally,this paper gives some key conclusions and future perspectives to provide insights for subsequent studies and commercial mining operations.

关键词： Deep seabed mining Marine engineering geology Geological disasters Environment Techniques

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Centrifuge experiment on the penetration test for evaluating undrained strength of deep-sea surface soils

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International Journal of Mining Science and Technology 2022年第2期32卷 363-373页

作者： Xingsen Guo Tingkai Nian Wei Zhao Zhongde Gu Chunpeng Liu Xiaolei Liu yonggang jia Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Environmental and Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUnited Kingdom

Rapid advances in deep-sea mining engineering have created an urgent need for the accurate evaluation of the undrained strength of marine soils,especially surface soils.Significant achievements have been made using full-flow penetration penetrometers to evaluate marine soil strength in the deep penetration;however,a method considering the effect of ambient water on the surface penetration needs to be established urgently.In this study,penetrometers with multiple probes were developed and used to conduct centrifuge experiments on South China Sea soil and kaolin clay.First,the forces on the probes throughout the penetration process were systematically analyzed and quantified.Second,the spatial influence zone was determined by capturing the resistance changes and sample crack development,and the penetration depth for a sample to reach a stable failure mode was given.Third,the vane shear strength was used to invert the penetration resistance factor of the ball and determine the range of the penetration resistance factor values.Furthermore,a methodology to determine the penetration resistance factors for surface marine soils was established.Finally,the effect of the water cavity above various probes in the surface penetration was used to formulate an internal mechanism for variations in the penetration resistance factor.

关键词： Static penetrometer Centrifuge experiment Deep-sea surface soil Undrained shear strength Penetration resistance factor Water cavity

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Tidal flat erosion of the Huanghe River Delta due to local changes in hydrodynamic conditions

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Acta Oceanologica Sinica 2014年第7期33卷 116-124页

作者： JIA Yonggang ZHENG Jiewen YUE Zhongqi LIU Xiaolei SHAN Hongxian Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China First Institute of Oceanology State Oceanic Administration Key Laboratory of State Oceanic Administration for Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration Department of Civil Engineering University of Hong Kong

An ideal nature system for the study of post-depositional submarine mass changing under wave loading was selected in the intertidal platform of the subaqueous Huanghe River Delta, a delta formed during period from 1964 to 1976 as the Huanghe River discharged into the Bohai Gulf by Diaokou distributary. A road embankment constructed for petroleum recovery on the inter-tidal platform in 1995 induced the essential varieties of hydrodynamic conditions on the both sides of the road. With both sides sharing similarities in （1） initial sedimentary environment, （2） energetic wave loading, （3） differential hydrodynamic conditions in later stages, （4） enough long-range action, and （5） extreme shallow water inter-tidal platforms; the study is representative and feasible as well. Two study sites were selected on each side of the road, and a series of measurements, samplings, laboratory experiments have been carried out, including morphometry, hydrodynamic conditions, sediment properties, granularity composition, and fractal dimension calculation of the topography in the two adjacent areas. It was observed that in the outer zone, where wave loading with high magnitude prevailed, the tidal flat was bumpy and exhibited a high erosion rate and high fractal dimension. Further, the fractal dimension diminished quickly, keeping with the enlarging of calculative square size. However in the inner zone, where the hydrodynamic condition was weak, the tidal fiat was fiat and exhibited a low erosion rate and low fractal dimensions; the fractal dimension diminished with the enlarging of calcu- lative square size. The fractal dimensions in the different hydrodynamic areas equalized increasingly as the calculative square size accreted to threshold, indicating that the hydrodynamic condition plays a significant role in topography construction and submarine delta erosion process. Additionally, the later differentiation of sediment properties, granularity composition, microstructure characteristics, and mineral composition induced by the diffe

关键词： hydrodynamic conditions coastal erosion sea-bed topography in-situ measurement fractal calculation

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