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1.
Sedimentary and structural evolution of the Eastern South Korea Plateau (ESKP), East Sea (Japan Sea)
The East Sea (Japan Sea) is a semi-enclosed back-arc basin that is thought to preserve a significant record of tectonic evolution and paleo-climatic changes of Eastern Asia during the Neogene. We use here 2-D regional multi-channel seismic reflection profiles and borehole data from Expedition 346 of the Integrated Ocean Drilling Program (IODP) to provide new constraints on the geological history of the Eastern South Korea Plateau (ESKP). The ESKP represents a structurally-complex basement high in the southwestern East Sea which formed during rifting of the back-arc basin. Our new observations show that the ESKP is composed of numerous horsts and grabens controlled by NE-trending normal faults. The acoustic basement is blanketed by Oligocene to recent sediments that have preferentially accumulated in topographic lows (up to 1.5 km thick) and have been cored during Expedition 346 at Site U1430 close to the southern margin of the ESKP. Seismic profiles in the ESKP reveal three units separated by regional unconformities. These seismic units closely correspond to IODP lithostratigraphic units defined at Site U1430, where biostratigraphic data can be used to constrain the timing of three main evolutionary stages of the ESKP. Stage 1 was related to rifting in the late Oligocene and middle Miocene, terminated by a regional uplift leading to an erosional phase in the middle Miocene. Stage 2 was associated with subsidence in the middle and late Miocene and uplift and accompanying erosion or non-deposition in the latest late Miocene. Stage 3 (Pliocene to present) recorded overall uniform hemipelagic-pelagic subsidence of the ESKP with short-lived tectonically-induced uplifts in the late middle Miocene and latest Miocene-early Pliocene. The three stages of evolution of the ESKP closely correlate to sedimentary changes since the Oligocene and suggest a direct control of regional/local tectonics on sedimentation patterns in the southwestern East Sea, with secondary influence of regional climatic and paleo-oceanographic processes. 相似文献
2.
The western South Korea Plateau in the East Sea (Sea of Japan) is occupied by rifted continental fragments formed in association
with the early phase of back-arc opening. The present study focuses on the seismic stratigraphy of the sedimentary succession
and the underlying acoustic basement in this region, based on closely spaced multichannel seismic reflection profiles. The
sedimentary succession occurs mainly within a series of subparallel basement troughs (grabens or half grabens) bounded by
faulted continental blocks (horsts) or volcanic ridges, and commonly floored by extrusive volcanic rocks showing hyperbolic
reflectors. These features are strongly suggestive of continental rifting accompanied by normal faulting, volcanic activity
and high rates of basin subsidence. The sedimentary succession can be subdivided into four seismic units. Unit 1 is characterized
by short and irregular high-amplitude reflectors and interpreted as a syn-rift deposit consisting of a non-marine volcanics/sediment
complex in topographic lows. Units 2 and 3 formed in an open marine environment during the Middle Miocene to Early Pliocene,
characterized by an onlap-fill and later draping marine sedimentary succession dominantly composed of hemipelagic sediments
and turbidites with frequent intercalation of mass-flow deposits. Along the western margin of the plateau, these units were
deformed under a compressional regime in the Early Pliocene, associated with the back-arc closing phase. Unit 4 (deposited
since the Early Pliocene) comprises hemipelagic sediments and turbidites with evidence of sporadic slides/slumps. 相似文献
3.
南海中北部中新世陆坡凹陷沉积充填与古陆坡形态演变 总被引：3，自引：0，他引：3
对中德合作“南海地球科学联合研究”和“中国边缘海的形成演化及重大资源的关键问题”的有关航次获得的地震资料进行层序地层和沉积相解释,并结合前人的研究成果,对南海中北部陆坡凹陷的构造和沉积特征进行了研究.研究结果表明,南海中北部陆坡区凹陷的构造演化经历了裂陷期、裂陷-坳陷过渡期和坳陷期三个阶段,沉积环境经历了河流-湖泊、浅海和深海的演化过程,不同演化阶段形成不同的地形形态.南海中北部地形演变可分为三个阶段,即早第三纪、早中新世-中中新世中期和中中新世中期-现在,其中早中新世中期-中中新世中期的沉积充填使陆坡形态发生了重要的转变,这次转变基本上奠定了现代意义上的陆架-陆坡-海盆的格局. 相似文献
4.
Variations in the calcite compensation depth (CCD) in the East Sea (Sea of Japan) since the early middle Miocene were inferred
from data on age-depth relationships, sediment carbonate, and benthic foraminifers from ODP sites 794, 795, and 797. The CCD
remained relatively shallow during much of the middle Miocene–Pliocene, and deepened sharply at the beginning of the Pleistocene.
Since then it has fluctuated rapidly, possibly in relation to the onset of the northern hemisphere glacial cycles in the late
Pliocene. The average CCD has deepened since at least the early middle Miocene, coinciding with the long-term drop in eustatic
sea level.
Received: 5 November 1998 / Revision accepted: 2 February 2000 相似文献
5.
日本海、鄂霍次克海和白令海的古海洋学研究进展 总被引：2，自引：0，他引：2
边缘海的存在使大陆和大洋之间的物质和能量交换变得相当复杂。在构造运动和海平面升降的控制下,边缘海和大洋之间时而连通时而隔绝,各种古气候变化信号都在一定程度上被放大。基于近期有关西北太平洋边缘海的古海洋学研究成果,简要概述了日本海、鄂霍次克海、白令海以及北太平洋地区自中新世以来的古气候和古海洋环境演化特征,并认为它们与全球其它地区一样也受控于因地球轨道参数变化引起的太阳辐射率的变化,大尺度的气候变化具有与地球轨道偏心率周期相对应的100ka周期,而41ka的小尺度周期则受地球自转轴斜率变化的控制。一些突发性的气候变化则是由气候不稳定性、海峡的关闭与开启和其它一些地球气候系统的非线性活动所驱动。但同时作为中高纬度边缘海,它们的古海平面、古海水温度、古洋流等古海洋环境因子的变化特征还受到冰盖扩张和退缩、构造运动、冰川性地壳均衡补偿、东亚季风等因素的影响,具有一定的区域特点。 相似文献
6.
In a broader application of sequence stratigraphic concept to a tectonically active margin setting, this study presents a sequence model that considers all three controls on sequence development (i.e. eustasy, tectonic movement and sediment supply) as independent variables. The model introduces six sequence types (A to F) including type 1 and type 2 sequences defined in the original Exxon scheme. Each sequence shows a variety in number and stacking pattern of its constituent parasequence sets reflecting combined effects of accommodation change and sediment supply. This model is applied to a seismic sequence analysis of the shelf–slope system (middle to upper Miocene) in the southwestern margin of Ulleung Basin which has experienced significant crustal deformation during the Tertiary back-arc opening and subsequent closing of the East Sea (Sea of Japan). The model application delineates four sequence types whose development is closely associated with the tectonic evolution of the Ulleung Basin margin. During the back-arc opening (early to middle Miocene), type A and B sequences were emplaced as a result of steady creation of accommodation space due to a rapid subsidence combined with a tectonic-controlled high to moderate rate of sediment supply. The sequences associated with the extensional tectonism are characterized by active progradation and aggradation without forced regressive phases. In the initiation stage of back-arc closure (middle to late Miocene), subsidence rates were significantly reduced because of a widespread contractional deformation, while subaerial erosion of the uplifted thrust belt resulted in an increase in sedimentation rate. As a result, steady prograding type-E sequences were formed by alternating normal and forced regressions. During the quiescent phase of back-arc closure in the late Miocene, rise-dominant fluctuating relative sea-level change and moderate to low sediment supply gave rise to type-F sequences (similar to type-1 sequences of the Exxon group) reflecting a major control of eustatic sea-level change. 相似文献
7.
Ocean Science Journal - High-resolution geochemical measurements were performed on core E09-08, which was taken from the top flat area of the Korea Plateau in the East Sea (Japan Sea). Based on... 相似文献
8.
J.-J. Cornée J. Butterlin P. Saint-Marc J.-P. Rehault C. Honthaas A. Laurenti-Ribaud C. Chaix M. Villeneuve Y. Anantasena 《Geo-Marine Letters》1998,18(1):34-39
In December 1995 we dredged early Miocene coral-reef carbonates and early/middle Pliocene slope carbonates outcropping on
the submerged Rama Ridge. This indicates that some of the Banda Sea Ridges were present during early Miocene times. Subsequent
major tectonic subsidence occurred between middle Miocene and early Pliocene times. These results concur with the hypothesis
of a relatively recent age for the North Banda Sea basement.
Received: 5 March 1997 / Revision received: 23 October 1997 相似文献
9.
G. N. Baturin 《Oceanology》2012,52(5):666-676
The lithology and geochemistry of the Miocene concretional phosphorites recovered from four submarine rises in the Sea of Japan (the North and South Yamato, the East Korean, and the Krishtofovich) were examined by means of analytical electron microscopy and ICP-MS chemical and microchemical elemental analysis. The microstructural studies and the data on the distributions of the 57 major and trace elements in these phosphorites revealed their close similarities to the Late Quaternary nodular phosphorites from the Namibian shelf, as well as phosphorites from other parts of the world, thus suggesting a common genetic affinity. Unlike the Namibian phosphorites, our samples collected from the Sea of Japan display a number of geochemical signatures indicative of volcanic and hydrothermal activity. This is supported by the presence of positive Ce and Eu anomalies in some samples and the Ga enrichment in a sample from the Chentsov Volcano. 相似文献
10.
Previously undocumented, migrating submarine canyons have developed in the Pearl River Mouth Basin along the northern continental margin of the South China Sea from the middle Miocene to present. A grid of high-resolution, 2-D multi-channel seismic profiles calibrated by borehole information permits documentation of these northeastward migrating submarine canyons, as the result of the interplay of gravity flows and bottom currents. The modern canyons have lengths of 30–60 km, widths of 1–5.7 km, and relief of 50–300 m in water depths of 450–1500 m. Buried ancient submarine canyon successions were originally eroded by basal erosional discontinuities and partially filled by canyon thalweg deposits. These are overlain by lateral inclined packages and hemipelagic drape deposits. Basal erosional discontinuities and thalweg deposits are probably created principally by turbidity currents and filled with turbidites. Lateral inclined packages likely were formed by along-slope bottom currents. The evolution of these migrating submarine canyons reveals that northeastward bottom currents have consistently occurred at least from the middle Miocene to present in the study area. It might further imply that thermohaline intermediate water circulation of the South China Sea has been anti-cyclonic from the middle Miocene to present. The initiation of migrating submarine canyons possibly signals commencement of strong bottom currents after the middle Miocene in the South China Sea. The intensification of bottom currents also possibly may reflect shoaling of the major ocean seaways and increased vigor in oceanic circulation forced by global cooling after the middle Miocene. 相似文献
11.
白垩纪末和新生代之交的构造运动揭开了新生代南海多旋回构造运动的序幕,自此之后整个南海的地壳开始进入总体受张性背景区域构造应力场控制、以张性沉降为主要特征的地质发展时期.七次区域性的构造运动和沉积作用具有多旋回、周期性振荡式发生的特点,其中尤以白垩纪末和老第三纪初、晚始新世和中渐新世及中中新世和晚中新世之间的三次构造运动表现最为强烈,形成了南海最为重要的三个区域性构造界面.南海地壳运动是欧亚、太平洋和印度—澳大利亚三大板块相互作用效应的结果和缩影,是跨越太平洋和印度—澳大利亚两大板块更大范围的岩石圈和软流圈流动(运动)方向、速度和强度的周期性振荡式改变所导致的. 相似文献
12.
Wenjing Ding Youchuan Li Lan Lei Li Li Shuchun Yang Yongcai Yang Dujie Hou 《海洋学报(英文版)》2023,42(3):31-53
The increase of total organic carbon content of the late Oligocene-early Miocene terrigenously-dominated marine shales in the shallower depth intervals was reported in the Ying-Qiong Basin, South China Sea. The organic enriched lower Sanya Formation shales(early Miocene) have biomarker characteristics of tropical/subtropical plants, with abundant high molecular weight n-alkanes, angiosperm-derived oleanane,rearranged oleananes Ⅰ, Ⅱ, Ⅱ, tricyclic/tetracyclic terpanes including des-A-oleanane, X, ... 相似文献
13.
南海海盆海山古地磁及海盆的形成演化 总被引：7，自引：0，他引：7
根据海山磁性反演获取的古地磁成果发现,南海海盆东部和西南部的运动形式、生成时代存在很大差异,东部海盆和西南部海盆之间由一条北北西走向的岩石圈压性左旋转换(性)断层——"南海海盆中央断裂"分界.结合已有的地质地球物理成果分析和论证,确定了南海海盆在古南海和与之接壤的华南地块南部边缘形成.南海海盆的形成演化分四个阶段:第一阶段,始新世"古南海断裂"产生,古南海被一分为二;第二阶段,渐新世东部海盆开始发育——扩裂;第三阶段,中中新世西南部海盆开始发育——张裂;第四阶段,南海海盆整体旋转,古南海圈闭. 相似文献
14.
国际海上救援效率比较研究 ——以东海特定水域为例 总被引：1，自引：0，他引：1
为研究东海海域海上救援效率和国际协作的协调性,以国际救援为视角,基于ArcGIS构建了海事救援效率评价模型。根据巡逻船舶密度数据确定了救援船舶的概率分布,得出了救援船舶与遇险船舶的可能距离,同时考虑了风浪影响下遇险船舶的漂移以及巡逻船舶失速的情况,分别计算了常风向和次常风向下中国、日本和韩国在东海特定水域的海上救援效率。结果表明:以各国现有的巡逻船舶配备对研究区内漂移的遇险船舶展开救援时,常风向下先后抵达的顺序为韩国、日本和中国,驰援时间分别为5.14、8.18和9.67 h;次常风向下抵达的顺序为韩国、日本和中国,驰援时间分别为5.45、8.25和10.08 h;为提高我国的救援效率,需要在东海海域部署9～10艘巡逻船舶开展常态化巡逻。本文研究可为我国有关部门科学制定和完善海上救援方案,调整海上救援力量配备,进一步加强国际间的协调与合作提供参考。 相似文献
15.
On tectonic movement in the South China Sea during the Cenozoic 总被引：1，自引：1，他引：0
The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and MidOligocene, during Mid and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and IndoAustralia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and IndoAustralia plates. 相似文献
16.
南海北部陆丰凹陷内LF14井记录了早中新世至早上新世的海相沉积地层。古水深重建结果显示研究井位在早中新世突然发生海侵, 水深迅速上升至最大值275m, 随后经数次波动, 整体处于中—外陆架环境, 共记录了5个完整的海侵—海退层序。回剥分析方法重建的LF14井沉降史揭示了研究井位在中中新世(17.5—10Ma)处于快速沉降期, 快速沉降导致的凹陷内沉积物的可容纳空间发育速率高和陆源物质供给充足是造成该阶段沉积速率高的两个重要因素; 晚中新世—早上新世(10—4.53Ma)处于弱沉降期, 推测东沙运动导致凹陷内的沉积物可容纳空间发育速率变小和陆源物质供给减少, 造成该时期内研究井位沉积速率低。最后, 依据定量重建的古水深变化在研究层段识别出一系列短暂存在的构造上升事件。 相似文献
17.
Compared to the northern South China Sea continental margin, the deep structures and tectonic evolution of the Palawan and Sulu Sea and ambient regions are not well understood so far. However, this part of the southern continental margin and adjacent areas embed critical information on the opening of the South China Sea (SCS). In this paper, we carry out geophysical investigations using regional magnetic, gravity and reflection seismic data. Analytical signal amplitudes (ASA) of magnetic anomalies are calculated to depict the boundaries of different tectonic units. Curie-point depths are estimated from magnetic anomalies using a windowed wavenumber-domain algorithm. Application of the Parker–Oldenburg algorithm to Bouguer gravity anomalies yields a 3D Moho topography. The Palawan Continental Block (PCB) is defined by quiet magnetic anomalies, low ASA, moderate depths to the top and bottom of the magnetic layer, and its northern boundary is further constrained by reflection seismic data and Moho interpretation. The PCB is found to be a favorable area for hydrocarbon exploration. However, the continent–ocean transition zone between the PCB and the SCS is characterized by hyper-extended continental crust intruded with magmatic bodies. The NW Sulu Sea is interpreted as a relict oceanic slice and the geometry and position of extinct trench of the Proto South China Sea (PSCS) is further constrained. With additional age constraints from inverted Moho and Curie-point depths, we confirm that the spreading of the SE Sulu Sea started in the Early Oligocene/Late Eocene due to the subduction of the PSCS, and terminated in the Middle Miocene by the obduction of the NW Sulu Sea onto the PCB. 相似文献
18.
Igneous intrusions emplaced within the prospective intervals of sedimentary basins can exert a significant impact on petroleum systems and hence are of considerable interest particularly when risking exploration plays. A number of discordant high amplitude seismic anomalies (DSAs) with a range of geometries are documented in high resolution 3D seismic data in the northern South China Sea. Their distribution and seismic characteristics are analysed and compared with similar seismic anomalies documented within sedimentary basins in the Atlantic margins and other locations. The DSAs occur mainly within Early Miocene strata and are interpreted as igneous intrusions that were emplaced close to the palaeo-seabed and are dated as early Middle Miocene using seismic-stratigraphic methods. A number of vents are also identified above the intrusions within early Middle Miocene strata. Several geometrical forms are observed, referred to here as saucer-shaped, lensoid-shaped, stacked and composite intrusions. The seismic expression of these is increasing complex towards the palaeo-seabed, with a tendency for the saucer-shaped sills to be the deepest intrusive forms. The igneous intrusions observed in this study only could be identified using 3D seismic data and they are important for the future evaluations of petroleum systems, basin evolution and tectonic analysis in the Pearl River Mouth Basin. 相似文献
19.
Neogene tectonic evolution of the Alboran Sea from MCS data 总被引：1，自引：3，他引：1
The structural framework of the northern Alboran Sea is one of a series of grabens or half-grabens developed during various Miocene rifting stages. MCS profiles and well data reveal early to late Miocene seismo-stratigraphic units affected by rifting. Three rifting episodes—latest Aquitanian-Burdigalian, Langhian-Serravalian, and Tortonian-are postulated to have caused significant extension and crustal thinning beneath the Alboran Sea. The middle Miocene episode led to major depocenters and triggered mud diapirism. Post-Tortonian tectonics modified the architecture of the Miocene Alboran Basin and formed the present structure, seafloor morphology, and boundaries of the Alboran Sea. 相似文献
20.
南海南部海域新生代万安运动的构造意义及其油气资源效应 总被引：15，自引：2，他引：13
南海南部海域在中中新世末发生了一次区域构造运动,被命名为万安构造运动。这次构造运动在新生代沉积中的表现是断裂、块断、挤压背斜和向斜。部分地区发育逆冲构造等。根据南海区域构造分析产生这次构造运动的起因可能与菲律宾海板块和欧亚板块于13MaBP在民都洛岛处发生碰撞．以及澳大利亚板块和欧亚板块在苏拉威西岛处发生碰撞(10MaBP)有关。这两次碰撞事件均对南海南部海域产生挤压,尤其是第一次碰撞挤压(向西方向)很强烈,是这次构造事件的主导因素。万安构造运动在南海南部海域沉积盆地中产生了许多挤压构造;而该海域沉积盆地中生烃的关键时刻是6MaBP,构造形成时间在生烃关键时间之前。因此,该海域形成了极其丰富的油气资源。 相似文献