The Kuroshio-related warm current system in the northern East China Sea significantly influences the climate, ecosystems, and fisheries of Northeast Asia. However, the relationship between the evolutions of Kuroshio Current (KC), Yellow Sea Warm Current (YSWC), and Tsushima Warm Current (TWC) since the middle Holocene is still elusive. In this study, by analyzing the variations in the upper ocean heat content and other proxy records in the Okinawa Trough, we investigated the changes in the KC strength, which exhibit significant fluctuations closely tied to El Nino-Southern Oscillation (ENSO) activity. The results reveal that KC and YSWC were intensified and TWC was weakened during 4.0-5.5 ka and 1.0-2.0 ka, under more La Nina-like conditions and strong East Asian Winter Monsoon (EAWM). Conversely, during 2.0-3.0 ka and 0.5-1.0 ka, El Nino-like conditions and the associated weaker EAWM were responsible for the diminished KC and YSWC and a stronger TWC. It suggests that the ENSO activity likely primarily controls the collaborative variations of these currents through modulating the KC and the monsoon. These findings provide insights for predicting future changes of the western pacific western boundary current system in the context of ongoing global climate change, emphasizing the need for continued high-resolution paleoceanographic studies.

To better understand the coupling between sedimentary and tectonic evolution in the East China continental margin, a 120.44-m-long borehole core designated CSH-01B was retrieved from the western margin of the North Yellow Sea. Paleomagnetic measurements revealed B/M, M/G and G/Gil boundaries at depths of 34.82 m, 86.58 m, and 119.98 m, respectively, yielding an extrapolated basal age of similar to 3.6 Ma. Alongside systematic investigations encompassing lithofacies discrimination, microfossil examination, and provenance identification based on detrital zircon U-Pb dating, the studied core was compared with extensively researched boreholes in the Yellow-Bohai Sea region. The sedimentary environment of the North Yellow Sea shifted since similar to 2.0 Ma from long-term lacustrine sequences with episodic fluvial deposition, akin to those in the Bohai Sea, to alternating fluvial and marine facies, resembling those in the South Yellow Sea. Additionally, sediments derived from south of the Qianliyan Uplift emerged, in contrast to those primarily delivered by outflows from the Bohai Paleolake previously. Therefore, the Qianliyan Uplift dividing the Yellow Sea must have subsided and/or collapsed at similar to 2.0 Ma. Concomitantly, the North and South Yellow Seas experienced subsidence and uplift, respectively, as indicated by their contrasting deposition rate trends. Quaternary marine transgressions began at similar to 1.7 Ma were hindered from affecting the Bohai Sea by the Miaodao Uplift until its subsidence and/or fragmentation during the Jaramillo subchron, along with the central South Yellow Sea, establishing a low-lying topographic corridor. Additionally, the provenance analysis in this study contributes new insights into the long-debated evolutionary history of the Yellow River. The prototype of the modern Yellow River must have emerged no later than 2.4 Ma and experienced an interruption at approximately 1.4 Ma. With the commencement of the large-scale marine transgression at similar to 0.8 Ma, the reintegrated Yellow River started to influence the East China continental margin widely and constantly.

The sediments provenance of the South Yellow Sea is controlled by many factors such as sea level change, ocean circulation, and neotectonic movement. The short time scale sediments provenance changes in this region since the Holocene have been revealed well, and a unified understanding has been formed that the central muddy area in the South Yellow Sea is a mixed area of the Yellow River sediments and the Yangtze River sediments. However, the contribution of different rivers to the sediments of the South Yellow Sea since late Quaternary is still ambiguous. Through comparative analysis of several boreholes with precise annual data constraints in the central mud area, the process of sediments provenance change at different periods since the late Early Pleistocene (1.0 Ma) was reconstructed, and the coupling mechanism of sediments provenance change and sea level change was established. It is found that during the period from 1.0 to 0.88 Ma, the seawater entered the South Yellow Sea along the Yellow Sea trough from the southeast to north as a channel, and there were different phenomena at the same time in different regions. Since 0.88 Ma, the sea water has been advancing from east to west. In addition, the sediments in the western of Jeju Island are mainly from China, and the sediments in the eastern are mainly from the Korean Peninsula, which roughly coincides with the boundary between the silty area and the sandy area on the eastern of the South Yellow Sea. In the surface sediments, the boundary line between the Yellow River sediments and the Yangtze River sediments is approximately 33.4° N.

The composition, provenance, and genetic mechanism of sediment on different sedimentary units of the East China Sea (ECS) shelf are essential for understanding the depositional dynamics environment in the ECS. The sediments in the northern ECS shelf are distributed in a ring-shaped distribution centered on the southwestern Cheju Island Mud. From the inside to the outside, the grain size goes from fine to coarse. Aside from the “grain size effect”, hydrodynamic sorting and mineral composition are important restrictions on the content of rare earth elements (REEs). Based on the grain size, REEs, and clay mineral composition of 300 surface sediments, as well as the sedimentary genesis, the northern ECS shelf is divided into three geochemical zones: southwestern Cheju Island Mud Area (Zone I), Changjiang Shoal Sand Ridges (Zone II -1), Sand Ridges of the East China Sea shelf (Zone II -2). The northern ECS shelf is mostly impacted by Chinese mainland rivers (the Changjiang River and Huanghe River), and the provenance and transport mechanism of sediments of different grain sizes is diverse. The bulk sediments come primarily from the Changjiang River, with some material from the Huanghe River carried by the Yellow Sea Coastal Current and the North Jiangsu Coastal Current, and less from Korean rivers. Among them, surface sediments in the southwestern Cheju Island Mud Area (Zone I) come mostly from the Changjiang River and partly from the Huanghe River. It was formed by the counterclockwise rotating cold eddies in the northern ECS shelf, which caused the sedimentation and accumulation of the fine-grained sediments of the Changjiang River and the Huanghe River. The Changjiang Shoal Sand Ridges (Zone II -1) were developed during the early-middle Holocene sea-level highstand. It is the modern tidal sand ridge sediment formed by intense hydrodynamic action under the influence of the Yellow Sea Coastal Current, North Jiangsu Coastal Current, and Changjiang Diluted Water. The surface sediments mainly originate from the Changjiang River and Huanghe River, with the Changjiang River dominating, and the Korean River (Hanjiang River) influencing just a few stations. Sand Ridges of the East China Sea shelf (Zone II -2) are the relict sediments of the paleo-Changjiang River created by sea invasion at the end of the Last Deglaciation in the Epipleistocene. The clay mineral composition of the surface sediments in the study area is just dominated by the Changjiang River, with the North Jiangsu Coastal Current and the Changjiang Diluted Water as the main transporting currents.

To better understand the compositions and sources of glycerol dialkyl glycerol tetraethers (GDGTs) and their use as proxies in the East China Sea (ECS), we analysed GDGTs in surficial sediments from the ECS outer shelf, slope and Okinawa Trough (OT) in open marine settings between 126°E and 129°E at water depths of either <100 or > 1000 m. The GDGT-0/Cren. values (0.35 ± 0.04) and methane index (MI) (0.17 ± 0.02) were generally low, indicating a negligible contribution of methanogenic Euryarchaeota GDGTs to the open marine settings in the ECS and that isoprenoid GDGTs (isoGDGTs) were mainly derived from marine planktonic Thaumarchaeota. Comprehensive analysis of the degree of cyclisation (DC) (0.34–0.53), #ringstetra (0.53–0.94), and IIIa/IIa (0.54–3.24) indices indicated that branched GDGTs (brGDGTs) may be predominantly produced in situ, with minimal soil contribution in this setting. The TEXH 86-derived sea surface temperatures (SST) were closer to the annual SST than the seasonal SST from the World Ocean Atlas (WOA) 2013. The methylation of the branched tetraethers (MBT) index correlated well with the mean annual bottom water temperature (BWT) from WOA 2013. Therefore, we propose that the MBT index from open marine settings in the ECS may reflect BWT changes in marine bottom environments.

The marine redox environment (MRE) plays a crucial role in the conversion and preservation of seafloor material and is a significant factor in the ocean carbon cycle. The evolution and driving mechanism of MRE are complex and present distinct regional characteristics over different time scales. The Okinawa Trough, situated in the East Asian monsoon realm, is influenced by the Kuroshio Current and flushing water, and its closed geographical pattern and multiple environmental factors make it highly sensitive to climate and marine environment changes. In this study, sediment samples from core GHN056-09 retrieved in the western Okinawa Trough were analyzed to investigate the high-resolution evolution of MRE since the mid-Holocene. The concentration of redox-sensitive elements (V, Co, Ni) and total organic carbon (TOC) were measured. Co/Ni and V/(V + Ni) values in the sediment samples indicated predominantly oxic conditions with matching productivity levels indicated by TOC (in the range of 0.28-1.17%). The oxic condition decreased during 6500-1500 a BP, and a strengthening trend was identified from 1500 a BP to present. By comparing these records with climate and environmental records, we found that weaker El Nin & SIM;o-Southern Oscillation (ENSO) and northward position of Intertropical Convergence Zone (ITCZ) resulted in less monsoon precipitation into the Okinawa Trough. Thinner freshwater lids could enhance seawater mixing at different layers, leading to strong oxic conditions. In contrast, stronger ENSO and southward position of ITCZ controlled by stronger solar insolation supplied more freshwater into the Okinawa Trough. Thicker freshwater barriers blocked the exchange of seawater from bottom to surface, resulting in weak oxic conditions. The trace element records in this study provide robust evidence on the high-resolution vari-ability of MRE driven by the frequency of ENSO, movement of ITCZ, and changes in regional precipitation. Our findings offer new insights into the evolution of MRE in response to global and local climate changes.

为深入了解东海外陆架表层沉积物物质来源及沉积环境特征,运用粒度和矿物学研究手段,对济州岛西南海域180个表层沉积物样品进行沉积物类型和碎屑矿物组成分析,探讨了矿物分布特征与沉积环境的相互关系,进一步明确表层沉积物的输运模式、物质来源及环流系统对其分布的影响.结果表明,研究区重矿物共34种,以普通角闪石、绿帘石和钛铁氧化物类矿物为主,橄榄石和变质岩矿物是区别内陆架沉积的标志性矿物.轻矿物共13种,以普遍发育的海绿石为特征.根据碎屑矿物组合分布特征,将研究区分为Ⅰ、Ⅱ两个矿物组合区,并进一步将Ⅱ区划分为两个矿物组合亚区.中部现代沉积区(Ⅰ区)矿物组合为普通角闪石-绿帘石-自生黄铁矿-钛铁氧化物类矿物-片状矿物,表现为现代陆源沉积特征,物质来源以黄河为主,生物沉积和自生沉积也是该区重要的沉积方式.外围残留沉积区(Ⅱ区)为沉积作用缓慢的弱还原环境,Ⅱ-1亚区矿物组合为普通角闪石-绿帘石-钛铁氧化物类矿物-石榴石-橄榄石,认为是以古长江的残留前积沉积为基底,受到Ⅰ区影响,接受了少量悬浮再悬浮的现代陆源沉积,同时又具有区域独特性.Ⅱ-2亚区矿物组合为绿帘石-普通角闪石-钛铁氧化物类矿物-石榴石,认为是古长江的残留沉积,在中部冷涡作用下,很少有现代物质的加入,区内不排除在当地环境生长的生物体作用下与Ⅰ区互相调整的物质.本研究为今后在东海外陆架深入开展沉积学、矿物学及环境演化研究提供了新的参考.

The epicontinental seas to the east of China have become highly anthropogenically impacted due to rapid economic development in recent decades, resulting in various environmental problems, including heavy metal pollution. The Bohai Strait, as a key junction connecting the material-energy exchange between the Bohai and Yellow Seas, is extremely critical in regional pollution prevention and control. To ascertain the spatial distribution and contamination levels of heavy metals in the surface sediments of the northern Bohai Strait, a systematic investigation was conducted. Geochemical analysis revealed that the concentrations (in ppm) of heavy metal elements in surface sediments vary in the range of 4.19–77.6 for As, 0.04–0.21 for Cd, 5.1–65.7 for Pb, 0.30–39.40 for Cu, 7.77–46.50 for Ni, 1.50–86.60 for Cr, 11.70–91.80 for Zn, and 0.005–0.038 for Hg. Ecological statistics indicate that the northern Bohai Strait suffers from prominent heavy metal pollution primarily induced by As, Cd, and Pb, accompanied by relatively weak pollution of Cu and Ni. Sediments collected from the submarine depressions and the southeast region exhibit higher heavy metal concentrations, and as a consequence, more serious ecological risk. Correlation analysis indicated that the accumulations of Hg, Cr, and Zn were associated with the deposition of organic matter. Preliminary provenance discrimination suggested that the pollutants were mainly derived from the eastern parts of the North Yellow Sea, rather than the Bohai region.

As a new type of pollutants in the marine environment, microplastics have attracted increasing attention from scientific researchers and environmental protection workers in China and abroad. However, for the microplastic pollution in sea areas in China, there are a very limited number of studies on its current status and few reviews of research on the microplastics. This paper reviews the surveys and researches of microplastics in the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea, and main estuaries in China carried out in recent years and proposes an outlook for future work, aiming to provide research suggestions and solutions for ecological protection against microplastic pollution in sea areas in China. Previous studies have shown that microplastics are widely distributed in water bodies and sediments in sea areas and major estuaries in China. The Pearl River Estuary, in the South China Sea suffers the most serious microplastic pollution, followed by the Bohai Sea. In contrast, the microplastic pollution in the Yellow Sea and the East China Sea is comparatively slight. Microplastics in sea areas in China are mainly fibrous and are concentrated in offshore areas with developed industry and a dense population (especially around estuaries and bays). In addition, they are widely affected by human activities, such as shipping, aquaculture, industry, and sewage discharge. Here the authors suggest unifying measurement units and research methods and developing related standard systems to carry out researches related to microplastics. Furthermore, this paper also suggests further deepening researches on both the source-sink process of microplastics and nanoscale microplastics while enhancing the development and implementation of related policies, aiming to promote researches and control of microplastics in sea areas in China.

对南黄海表层沉积物稀土元素数据进行了系统总结,旨在揭示其赋存特征、分布规律及主要来源.结果表明,南黄海稀土元素含量为77.2～261.78 μg/g,平均值为166.46 μg/g;空间上分布规律显著,高值区出现在南黄海中部泥质区,含量基本在180 μg/g以上,而低值区则呈斑块状出现在靠近山东半岛近岸一带,含量多低于130 μg/g.稀土元素的球粒陨石配分模式和上陆壳(UCC)配分模式显示各海域总体特征较为一致,与中国大陆的稀土元素配分曲线类似,指示了较强的陆源特征,河流携带的陆源入海物质是其主要的物质来源.通过对稀土元素各特征参数进行相关性分析,发现南黄海稀土元素组成与沉积物粒度呈较为明显的正相关,表明了沉积物粒度、矿物组成对稀土元素含量具有显著的控制作用.对比分析稀土元素空间分布规律和南黄海主要入海河流沉积物稀土组成,结果表明南黄海绝大部分沉积物来自于中国大陆河流,包括长江、黄河和老黄河等大型河流.在不同环流体系控制下,大型入海河流控制了南黄海不同区域的物质分布:西北部主要来自黄河入海物质,山东半岛沿岸流是其主要输运动力;老黄河物质主要沉积在西部海域,主要驱动力是苏北沿岸流;南部物质主要来自长江入海物质,长江冲淡水和闽浙沿岸流控制了其分布范围;东部近岸区域则以朝鲜半岛入海河流携带陆源物质为主,主要输运动力为朝鲜沿岸流.在此基础上,以La/Yb=11.7为界,可将整个南黄海划分为两个物源区,西部大部分海域为中国大陆来源,而东部近岸区则为朝鲜半岛来源,两者分界线基本接近于黄海海槽的位置.总体而言,大中型河流带来的陆源物源、沉积物粒度以及海域流系格局控制了南黄海表层沉积物稀土元素的组成特征和分布格局.

Although many studies have been carried out on the mud wedge in the inner shelf of the East China Sea (ECS), the sediment sources and seismic textures of the mud wedge are still unclear and remain controversial. Therefore, this study utilizes grain size and clay mineral analyses of surficial sediment samples and high-resolution sub-bottom seismic profile interpretation to identify the provenance and texture of these mud wedge sediments. The results show that sediment sources on the inner shelf of the East China Sea are mixed by the Yangtze River, small mountainous rivers along the Zhejiang-Fujian, and western Taiwan coasts. The sediments derived from the Ou and Min rivers are mainly concentrated in the shallowest shelf area within a water depth of 20 m which is located north of the Min River Estuary. Their contribution to the estuaries and coastal areas reflects the different sediment transport patterns of the two small mountainous rivers. The thickness of the Holocene mud wedge between Hangzhou Bay and Taizhou Bay is greater than 20 m at a water depth of approximately 10 m. The cause of this phenomenon is possibly related to the presence of the Zhoushan Islands, which are distributed along the Zhejiang coast and appear to effectively trap sediments from the Yangtze River, facilitating sediment accumulation. The findings of this study will help improve our understanding of the sediment transport and deposition mechanism of deposition on the inner shelf of the East China Sea.

0 引言 长山列岛又称庙岛群岛,指山东省烟台市蓬莱区北部所辖32座岛屿的总称.其中,南长山岛等南五岛与北隍城岛等北五岛共10座岛屿构成列岛的主体(图1).在地理位置上,长山列岛为渤、黄海的分界线.

对南黄海中部泥质区南侧4个表层沉积物和SYS90-1A孔中5个沉积物样品进行碎屑锆石U-Pb定年,具体分析了研究区表层沉积物物源差异及约1.0 Ma以来沉积物物源变化.结果显示,泥质区沉积物主要来自黄河,而泥质区外部南侧沉积物可能主要由长江供应.SYS90-1A孔主要记录了早更新世晚期以来的沉积记录,不同时期物源差异明显:中更新世早期以长江源物质为主,利用磁化率开展旋回地层学分析,根据天文年代调谐确定该时期具体时代为0.59～0.71 Ma;早更新世晚期至中更新世以及中更新世中期以来以黄河源物质为主.这一结果与前人关于南黄海早更新世以来沉积物以黄河源物质为主的认识不同,长江源物质对南黄海泥质区沉积物贡献需要重新认识.上述表层沉积物样品和钻孔沉积物样品碎屑锆石U-Pb年龄分布与朝鲜半岛河流沉积物完全不同,说明该区域自早更新世晚期以来沉积物主要来自中国大陆.

The environmental evolution and provenance of the sediments since 1.2 Ma penetrated by the borehole of JXC-1 in Northwestern Liaodong Bay are studied in this paper using the data from accelerator mass spectrometry C-14 dating, optically-stimulated luminescence dating, paleomagnetic dating, qualitative and quantitative analysis of benthic foraminifera, and the geochemistry analysis. Based on regional stratigraphic correlation, the evolution of sedimentary environment and provenance are discussed. The study suggests that large-scale transgression began by the end of Middle Pleistocene, and invaded into this region for three times from Late Middle Pleistocene to Holocene, in MIS 7, MI55, and MIS1, that is in consistent with the global pattern of sea level changes. The results of this study are different from previous researches in the Bohai Sea, which found three times of transgressions in MI55, MI53, and MIS1 respectively. There are two possibilities, either no transgression in the Bohai Sea, or the transgression did not enter Liaodong Bay during the time of MI53. Provenance analysis shows that the northwest of Liaodong Bay is a mixed depositional area. Sediments are mainly sourced from the Yellow River, Liaohe River (formerly Shuangtaizi River) and Daliao River. During the three marine phases, the sediments of the JXC-1 borehole came mainly from the Yellow River characterized by high content of CaO, and deposited under the control of Bohai Sea circulation and coastal currents. The sediments in depths of 36.00-46.00 m and 58.20-70.30 m of the borehole are high water level lacustrine sediments, mainly came from the Yellow River. However, the sediments in depths of 46.00-58.20 m are mainly brought in by the Liaohe and Daliao rivers. All these studies suggest that the sediments coming from the Yellow River may be distributed northward up to 40.5 degrees N. As a major conclusion different from previous understandings, this paper provides an important reference for the evolution of the sedimentary environment and the provenance of the Late Quaternary deposits of the Bohai Sea.

0 引言 软沉积变形(soft-sediment deformation)是指出现于未固结沉积物中的变形,其形成于沉积过程中或沉积后至发生显著成岩(固结)作用之前.软沉积变形构造的触发机制可以分为地震和非地震2类.其中,古地质历史时期保存的与地震相关的软沉积变形构造是区域地层对比、灾变沉积学研究及古地震研究的重要线索.2021年7月,青岛海洋地质研究所"黄海长山列岛海域1∶5万海洋区域地质调查"项目组在开展针对长山列岛的海岛野外地质调查工作中,于砣矶岛新元古代蓬莱群豹山口组地层中首次识别出系列软沉积变形构造,为研究该地区蓬莱群沉积期的古地理格局、区域地层对比等提供了重要线索.

中国海域拥有宽广的大陆架,同时还有陆坡和深海盆,有众多河流入海并输入巨量的陆源物质,沉积物记录了海陆变迁、环流变化、海平面升降、物质输送和气候变化等环境信息.沉积物的粒度特征可以反映沉积动力、物质来源和搬运距离等,可以通过沉积物粒度组成、参数及各种图解来研究沉积环境的变化.前人对中国海域表层沉积物的粒度分布特征展开了大量的研究,取得了丰富的研究成果,但这些研究多集中在某一海域或区域,缺乏对整个中国海域的表层沉积物类型的宏观系统认识.本文基于中国地质调查局"1∶100万海洋区域地质调查项目"获取了中国海域4300个海底表层沉积物样品,通过沉积物粒度分析,结合前人已发表资料,对中国海域表层沉积物的沉积类型特征、物质来源和运移模式等开展了系统的研究.本文把浅海和半深海沉积物按照含砾石和不含砾石主要划分出5个和7个沉积物类型,深海沉积物主要划分了9个沉积类型,研究结果表明:中国海域表层沉积物沉积类型多样、来源复杂,主要受控于物质来源、水动力条件和地形地貌的变化,在东部海域总体呈现"大江大河-宽缓陆架-残留慢速沉积"的条带状沉积分异模式,而在南部海域呈现的是"短源性河流-多类型陆架-重力流快速沉积"的环带状沉积分异模式.本文的结果对研究中国海域沉积物的宏观分布规律提供了基础资料,对理解海洋沉积动力过程具有重要意义,同时沉积物粒度的特征对海底砂矿分布也具有指示意义.

Downcore geochemical composition of sediment core retrieved from the central Andaman Sea were measured to help understanding the potential connection between chemical weathering and monsoon climate since the last glacial period. The age model was confirmed based on twelve accelerator mass spectrometry (AMS) C-14 dates on planktonic foraminifera Neogloboquedrina dutertrei. Provenance discrimination results distinguished by Rare Earth Elements pattern and Sc/Th-(La/Yb)(UCC) diagram revealed that terrestrial sediment from the Irrawaddy River are the dominant input in the central Andaman Sea. Chemical weathering indexes, including chemical index of alteration (CIA), weathering index of Parker (WIP), alpha Na-Al, and a stack of these data were reported and the terrestrial input was assessed using Ti/Ca ratios. These indexes showed general synchronicity with the regional monsoon precipitation and temperature record, the chemical weathering intensity and monsoon precipitation/temperature were stronger/higher during MIS 3 and MIS 1 and weaker/lower during MIS 2, indicating existence of a general "climate-driving weathering" pattern on glacial-interglacial time scales. However, certain anomalies occurred during 18-13 cal. kyr BP and 6-3 cal. kyr BP, when the chemical weathering intensity showed higher and lower values, respectively. The chemical weathering intensity enhanced during 18-14 cal. kyr BP, due to increased isolation and markedly increased temperatures, as well as lower erosion production and sediment transfer rate caused by lower precipitation, whereas the opposite conditions prevailed during 14-13 cal. kyr BP. Indeed, for the weak chemical weathering intensity during 6-3 cal. kyr BP, decreased isolation, relatively high terrestrial sediment supply, slightly lower precipitation and markedly lower temperatures were suggested to be the primary reasons, indicating the presence of a "climate-driving weathering" pattern on millennial time scales. Our findings support the hypothesis that the chemical weathering evolution in the north-eastern Indian Ocean was synchronous with both global and regional climate conditions, representing distinct changes controlled by Indian summer monsoon on different time scales.

中国东部中—新生代构造活动主要受太平洋板块和菲律宾板块与欧亚板块相互作用的控制.近年来,地球系统多圈层构造观的提出为深入理解东亚洋陆汇聚系统各圈层之间的相互作用提供了新的思维.本文以地球系统多圈层构造观为指导,依托1∶100万海洋区域地质调查实际资料与成果,在东亚大陆边缘多圈层动力系统的框架内,对中国海域及邻区的地质构造进行了总结,初步形成了以"一个边缘、两次消减、三期伸展、分层控制"为核心的"东亚洋陆汇聚边缘多圈层相互作用"理论模式,并进一步提出新的构造单元划分方案.本文首次将大洋板块与大陆边缘稳定地块之间的区域,划分为"东亚大陆边缘汇聚带"这一独立的一级构造单元,按照构造演化的差异,以台湾岛界大致可以分为北部的日本—琉球段和南部的菲律宾段."东亚大陆边缘汇聚带"以全新视角诠释了中—新生代以来在西太平洋俯冲汇聚系统下,东亚大陆发生的多期次地质构造事件的深部板块动力学过程,特别是在菲律宾海板块俯冲背景下,形成了中国海域东部带状变化、南部环状变化的地貌特征.海域地貌格局进一步控制了东部海域"大江大河—大三角洲—陆源碎屑—条带状"和南部海域"短源河流-高角度陆坡-混合物源-环状分布"的沉积分异模式.

As one of the most important margin seas around the west Pacific, the eastern China seas are important sink for terrigenous materials and forms multiple geology structures. So research the composition and spatial distribution of sediments could help us to understand the dynamics mechanism of the marine sedimentary environment, further to comprehend the land-sea interaction process. Based on high spatial resolution sediment survey in the eastern China seas, the distribution diagram of the sediment types was compiled to reveal the space regularities of sediment. In this study, the Principal Component Analysis (PCA) method was used to identify the controlling factors that are the main controls of the sediment distribution in the study area, which revealed three factors (F1, F2 and –F1) representing grain size categories of >5.75φ, 4.25–5.75φ and 1.50–3.00φ, respectively. F1 represents fine sediments (>5.75φ), -F1 represents coarse sediments (1.50–3.00φ), and F2 represents intermediate-sized sediments (4.25–5.75φ). The sediment transport patterns of the different grain size categories in the eastern China seas are discussed in the context of a comprehensive analysis of sediment grain size composition, material sources, flow patterns, and other factors. The results show that fine-grained sediments represent a “distant” sink of terrigenous material that formed in a stable and low-energy sedimentary environment. The coarse sediment deposits were formed in the late Pleistocene when the hydrodynamic conditions were relatively strong, and the intermediate-sized sediments were distributed in an area with a high concentration of suspension representative of mid-strength hydrodynamic conditions.