共查询到20条相似文献，搜索用时 31 毫秒
1.
O. V. Stepanyan 《Doklady Earth Sciences》2014,458(1):1158-1160
Currently, the species list of the macroalgae (excluding Charales) inhabiting the southern seas of Russia includes 388 species, specifically, 362 species in the Black Sea, 46 species in the Sea of Azov, and 70 species in the Caspian Sea. The species list has been increased by approximately 30% (96 species, most of them are registered in the Black Sea), compared to the data obtained 30 years ago. The green and red macroalgae of warm-water Mediterranean and tropical origin (Ceramium, Polysiphonia, Laurencia, Ulva, and Chaetomorpha) and brown algae (Sargassum and Cytoseira) were the key invaders. Nowadays the maximal species diversity is found on the Crimean coast and the Turkish coast of the Black Sea; and the species list of the Turkish coast differs significantly from all the other studied sites of the Black Sea. The number of the algae of the warm-water complex increased the most in 1990s–2000s in the Black Sea; species of boreal-tropical and subtropical origin dominate. However, such a tendency was not observed in the Sea of Azov and in the Caspian Sea, but expansion of the habitats of the brackish green algae has been registered. 相似文献
2.
The results of study of the deep sources of volcanic rocks from the Sea of Japan and the Philippine Sea with continental and oceanic basements, respectively, are presented. This problem is considered with the example of alkaline volcanic rocks of the Middle Miocene to Pliocene complex of the Sea of Japan and the Eocene–Oligocene Urdaneta Plateau of the Philippine Sea. The rocks have a similar geochemistry typical of OIBs, which indicates their deep (plume) origin. The presence of the Oligocene calc-alkaline volcanic rocks, which were formed prior to the marginal sea volcanism in the Sea of Japan, however, is the main difference in volcanism of the Sea of Japan from that of the Urdaneta Plateau, and this is explained by the different basements of these seas. 相似文献
3.
A study of Mean Sea Level (MSL) determination in the Aegean Sea is carried out. First, MSL values have been computed at a number of tide gauge stations. Then, Sea Surface Heights (SSHs) have been determined based on GEOSAT altimeter data of Geodetic Mission (GM). The computed SSHs were fitted to the tide gauge MSL values using a 4-parameters model. The best fitting agreement reached the level of 5cm, when GPM98A geopotential model was used as a reference surface. 相似文献
4.
V. P. Utkin 《Doklady Earth Sciences》2017,472(2):167-172
Based on the concept of tectonic delamination of the lithosphere, we revealed that the Sea of Japan and the Sea of Okhotsk were formed as a result of the tectonic flow of crustal material. The intermittent southward movement of southwestern Japan (Late Cretaceous–Cenozoic) along the eastern Japanese leftlateral strike-slip fault zone resulted in the formation of paired structures: back-arc extensional (Central Japan rift) and frontal compressional (South Japan imbricate–thrust belt) structures. The Sea of Okhotsk was formed in a similar tectonic setting: South Okhotsk rift (back-arc extensional structure) and Kamuikotan–Susunai compressional belt (frontal imbricate-thrust structure). Synchronous extension, compression, and strike-slip movements suggest that the tectonic flow of crustal material played a critical role in the formation of the Sea of Japan and the Sea of Okhotsk. 相似文献
5.
南海盆地中生代海相沉积地层分布特征及勘探潜力分析 总被引：7，自引：1，他引：6
南海盆地中生代海相地层是古南海沉积产物,主要分布于南海北部陆架珠江口盆地东部,南海南部西北巴拉望、礼乐滩和南薇西-北康盆地及其附近,地层厚度在2 500~5 000 m,分布面积合计在125 000 km2以上。南北两地中生界被古老基底和新生代洋壳隔开,加里曼丹岛北侧-北巴拉望一线为古南海消亡的缝合带。南海盆地中生代生物源以浮游生物为主,干酪根为III型,以生气为主。油气生成、运移与圈闭形成的匹配关系良好,可形成自生自储型油气藏、新生古储型油气藏和古生新储型油气藏。由此可见,南海盆地中生代海相沉积岩具有较好的勘探潜力。 相似文献
6.
This paper reports the results of petrographic and geochemical studies of the Miocene-Pleistocene volcanic rocks that accompanied
the formation of the deep-water basins of the Sea of Japan and Sea of Okhotsk. The geochemical types of these rocks, their
geodynamic settings, and their derivation from different magmatic sources were determined. The marginal-sea basaltoids of
the Sea of Japan are derivatives of fluid-enriched mantle (EMI), while the volcanics of the Kurile basin were generated from
mantle enriched in continental crust (EMII). In spite of the different conditions of their genesis, they share some common
geochemical features, in particular, their calc-alkaline signatures. These traces of the influence of sialic crust on magma
generation confirm the development of the basins of both these seas on continental basement. 相似文献
7.
Christiaan G. C. van Baak Eleanora P. Radionova Larisa A. Golovina Isabella Raffi Klaudia F. Kuiper Iuliana Vasiliev Wout Krijgsman 《地学学报》2015,27(6):433-441
Past hydrological interactions between the Mediterranean Sea and Black Sea are poorly resolved due to complications in establishing a high‐resolution time frame for the Black Sea. We present a new greigite‐based magnetostratigraphic age model for the Mio‐Pliocene deposits of DSDP Hole 380/380A, drilled in the southwestern Black Sea. This age model is complemented by 40Ar/39Ar dating of a volcanic ash layer, allowing a direct correlation of Black Sea deposits to the Messinian salinity crisis (MSC) interval of the Mediterranean Sea. Proxy records divide these DSDP deposits into four intervals: (i) Pre‐MSC marine conditions (6.1–6.0 Ma); (ii) highstand, fresh to brackish water conditions (~6.0–5.6 Ma); (iii) lowstand, fresh‐water environment (5.6–5.4 Ma) and (iv) highstand, fresh‐water conditions (5.4–post 5.0 Ma). Our results indicate the Black Sea was a major fresh‐water source during gypsum precipitation in the Mediterranean Sea. The introduction of Lago Mare fauna during the final stage of the MSC coincides with a sea‐level rise in the Black Sea. Across the Mio‐Pliocene boundary, sea‐level and salinity in the Black Sea did not change significantly. 相似文献
8.
威德尔海的重磁场特征及其构造意义 总被引：1，自引：1，他引：0
威德尔海是南极洲最大的边缘海。通过搜集威德尔海的重磁资料、历史文献以及总结前人的相关研究成果,介绍了威德尔海的重磁场基本特征以及指示的构造意义。威德尔海最显著的重力特征是在威德尔海的中北部分布着以鲱骨式结构展布的一系列NW-SE向重力异常,其上可见一系列弧形、上凹的以E-W为主要方向的磁力异常。沿南极半岛陆架边缘的重力高一直可延伸到南侧海域,高值区与陆架平行,但是在磁异常上反映不明显。威德尔海原始海盆的形成约在150 Ma,并伴随南北向张裂,随后在140 Ma发生东西向扩张,到约120 Ma异常形成现代南极洲、非洲和南美洲板块的分布格局,鲱骨式结构异常脊也形成于该时期。 相似文献
9.
10.
Ian S. F. Jones 《Journal of Earth System Science》2002,111(3):209-213
The Sulu Sea, located between Borneo and the Philippines, is separated from the surrounding ocean by two chains of islands.
There are no passages below 500 m depth and the basin, which at the deepest is 5,000m, is filled with warm low oxygen water.
The near surface chlorophyll concentration has been examined with the aid of ocean colour sensors on board satellites. Direct
comparisons between a field observation of chlorophyll and its remotely sensed values from OCTS (Ocean Colour Temperature
Scanner) are found to be in satisfactory agreement. An 8-month time series of chlorophyll near the centre of the Sulu Sea
has been used to show that the chlorophyll level is significantly higher than the level in the adjacent South China Sea. This
was most pronounced at the period of change between the monsoons. The greater primary productivity may provide the explanation
for the higher deposition rate of carbon in the Sulu Sea.
Although the Sulu Sea is more productive than the adjacent South China Sea, the central area can still be classified as a
desert. Estimates of the new primary production in the central Sulu Sea seem to be just sufficient to support the current
fishery. 相似文献
11.
Nikishin A. M. Startseva K. F. Verzhbitsky V. E. Cloetingh S. Malyshev N. A. Petrov E. I. Posamentier H. Freiman S. I. Lineva M. D. Zhukov N. N. 《Geotectonics》2019,53(6):635-657
Geotectonics - The seismic stratigraphy scheme for the shelf basins of the East Siberian Sea and the Chukchi Sea region and the adjacent deepwater area of the Amerasia basin has been developed, and... 相似文献
12.
格陵兰海海冰外缘线变化特征分析 总被引：2，自引：0，他引：2
格陵兰海作为北冰洋的边缘海之一,容纳了北极输出的海冰,其海冰外缘线的变化既受北极海冰输出量的影响,也受局地海冰融化和冻结过程的影响。利用2003年1月到2011年6月AMSR-E卫星亮温数据反演的海冰密集度产品,对格陵兰海海冰外缘线的变化特征进行了分析。结果表明,格陵兰海海冰外缘线不仅存在一年的变化周期,还存在比较显著的半年变化周期,与海冰在春秋两季向岸收缩有关。格陵兰海冬季的海冰外缘线极大值呈逐年下降的趋势,体现了北极增暖导致的冬季海冰范围减小;而夏季海冰外缘线离岸距离的极小值呈上升趋势,表明夏季来自北冰洋的海冰输出量增大。2003—2004年是格陵兰海夏季海冰融化最严重的2年。2007年北冰洋夏季海冰覆盖范围达到历史最小;而格陵兰海夏季的最小海冰范围最大,表明2007年北冰洋海冰的输出量大于其他年份。此外,夏季格陵兰岛冰雪融化形成的地表径流对海冰外缘线有一定的影响。对海冰外缘线影响最大的不是格陵兰海的局地风场,而是弗拉姆海峡(Fram Strait)区域的经向风,它直接驱动了北冰洋海冰向格陵兰海的输运,进而对格陵兰海海冰外缘线的分布产生滞后的影响。 相似文献
13.
《Geochimica et cosmochimica acta》1999,63(19-20):3457-3466
By using catalytic current polarography and high-resolution inductively coupled plasma mass spectrometry, W and Mo in seawater were determined in the Okinawa Trough, a backarc rift, and in the East China Sea and the Yellow Sea. Mo was distributed conservatively throughout the study area, and its salinity-normalized concentration was 104 ± 6 nM (n = 105). W was also uniformly distributed south of the Kuroshio Current (56 ± 7 pM, n = 51). Anomalous high concentrations of W (maximum 254 pM) were found in the Iheya Graben in the middle Okinawa Trough (>1000 m depth), which were probably supplied by hydrothermal activity. The concentrations of Mo and W in the East China Sea and the Yellow Sea showed linear correlation with salinity (26 < S < 35). The Mo data can be explained by mixing of seawater and river water of the Changjiang (Mo = 10 nM; Qu et al., 1993). However, the values of W extrapolated to S = 0 were largely different between two cruises (1200 pM in May–June 1987 and 540 pM in June 1994) and much higher than the reported concentrations of 160 pM for world rivers by Turekian (1969) and 30 pM for unpolluted Japanese rivers by Sohrin et al. (1989). Moreover, significantly high W was observed in the bottom water at stations near the Changjiang River estuary and the western Yellow Sea. While these data may suggest that W is released from the anoxic sediments of the continental shelf, we need more data to elucidate the mechanism controlling the distribution of W. 相似文献
14.
The Dead Sea rift is considered to be a plate boundary of the transform type. Several key questions regarding its structure and evolution are: Does sea floor spreading activity propagate from the Red Sea into the Dead Sea rift? Did rifting activity start simultaneously along the entire length of the Dead Sea rift, or did it propagate from several centres? Why did the initial propagation of the Red Sea into the Gulf of Suez stop and an opening of the Gulf of Elat start?
Using crustal structure data from north Africa and the eastern Mediterranean and approximating the deformation of the lithosphere by a deformation of a multilayer thin sheet that overlies an inviscid half-space, the regional stress field in this region was calculated. Using this approach it is possible to take into account variations of lithospheric thickness and the transition from a continental to an oceanic crust. By application of a strain-dependent visco-elastic model of a solid with damage it is possible to describe the process of creation and evolution of narrow zones of strain rate localization, corresponding to the high value of the damage parameter i.e. fault zones.
Mathematical simulation of the plate motion and faulting process suggests that the Dead Sea rift was created as a result of a simultaneous propagation of two different transforms. One propagated from the Red Sea through the Gulf of Elat to the north. The other transform started at the collision zone in Turkey and propagated to the south. 相似文献
15.
海冰变化与全球气候、 生态系统和人类活动密切相关, 海冰厚度是海冰变化研究的重要参数之一。全面立体高精度观测海冰厚度的最有效手段是航空遥感, 而冰桥计划（IceBridge）是当前南北极最大的航空遥感工程。基于2009 - 2014年冰桥计划的激光雷达高程数据和数字测图系统相机光学影像对南极别林斯高晋海的海冰厚度进行研究, 并结合降雪量等气象数据探讨该区域海冰厚度变化的原因。研究发现该海域的海冰厚度在2009 - 2014年间整体呈微弱增长趋势（0.07 m·a-1）, 但是在95%置信水平下不具有显著性。2009 - 2011年呈现先增加后减少的大幅度变化, 其中2010年达到极大值2.42 m, 之后开始缓慢增加。海冰厚度的年际变化与降雪和近地表温度等气象要素相关, 二者相比较而言降雪为主要影响因素。 相似文献
16.
A. M. Nikishin A. O. Khotylev A. Yu. Bychkov L. F. Kopaevich E. I. Petrov V. O. Yapaskurt 《Moscow University Geology Bulletin》2013,68(3):141-154
Deposits in southwestern Crimea that contain Late Albian, Middle Senomanian, and Middle Campanian volcanic material are described and dated. Supposedly volcanic edifices are identified in the Black Sea (the Shatsky Swell) based on seismic data. The Albian, Senomanian, and Campanian volcanic belts are reconstructed for the entire Black Sea Region. The suggestion is made that the Black Sea Basin formed as a back-arc basin that started from rifting in the Albian and finished with spreading of the oceanic crust in the Senomanian-Early Santonian. 相似文献
17.
J.D. Fairhead 《Tectonophysics》1973,20(1-4):261-267
Seismic refraction profiles now number 9 in the Gulf of Aden and 15 in the Red Sea with a further intensive study by the Cambridge University group between latitudes 22 and 23°N. The results of these surveys indicate that the main trough of the Gulf of Aden is underlain by oceanic crust while only the deep axial zone and a questionable amount of the main trough of the Red Sea are underlain by oceanic crust.
Seismic reflexion profiles reveal the nature of Layer 1 and the upper surface of Layer 2. A strong subbottom reflector is found beneath the main trough of the Red Sea at 0.5 km but is found to be absent in the axial zone. This survey together with the refraction work and geological evidence suggests a complex history for the main trough of the Red Sea. Reflexion profiles and dredging in the Gulf of Aden indicate that the thickness of sediments increases away from the central rough zone and that the sediment is underlain by volcanic material. 相似文献
18.
The purpose of the present study was to study the tectonics of the Yellow Sea. Although oil- gas exploration has been undertaken for more than 30 years in the southern Yellow Sea, the exploration progress has achieved little. There are three tectonic periods with near N–S trending shortening and compression (260–200 Ma, 135–52 Ma and 23–0.78 Ma) and three tectonic periods with near E–W trending shortening and compression (200–135 Ma, 52–23 Ma and 0.78 Ma) at the Yellow Sea and adjacent areas during the Mesozoic and Cenozoic. The Indosinian tectonic period is the collision period between the Sino-Korean and Yangtze Plates, which formed the basic tectonic framework for the Yellow Sea area. There were strong intraplate deformations during the Yanshanian (200–135 Ma) and Sichuanian (135–52 Ma) periods with different tectonic models, which are also the main formation periods for endogenic metallic mineral deposits around the Yellow Sea. The three tectonic periods during the Cenozoic affect important influences for forming oil-gas reservoirs. The Eocene–Oligocene (52–23 Ma) is the main forming period for oil-gas sources. The Miocene–Early Pleistocene (23–0.78 Ma) was a period of favorable passage for oil-gas migration along NNE trending faults. Since the Middle Pleistocene (0.78 Ma) the NNE trending faults are closed and make good conditions for the reservation of oil-gas. The authors suggest that we pay more attention to the oil-gas exploration at the intersections between the NNE trending existing faults and Paleogene– Neogene systems in the southern Yellow Sea area. 相似文献
19.
南黄海悬浮体的垂直分布特性及其指示意义 总被引：3，自引：0，他引：3
重点研究了南黄海典型断面的悬浮体垂直分布特性及其指示意义。结果表明:四季南海黄海北部断面悬浮体分布的共同特征是西高东低,冬、春季鲁北沿岸流携带悬浮体向南输运和黄海暖流北上是南黄海与北黄海进行物质交换的重要方式和途径;夏半年南黄海中部断面深水域存在的表层云团状悬浮体高值区或"中层悬浮体最大值"现象与该海域的生物活动具有密切的联系;冬、春季苏北浅滩外侧海域近岸区的悬浮体含量显著高于夏、秋季,且冬半年近岸区的悬浮体具有向外海输运的趋势;长江口东北部断面各季节均存在2个悬浮体高值区,其中位于断面西部近岸海域的高值区与长江冲淡水(夏季)或苏北沿岸水(冬季)的影响有关,位于断面东部深水域处的悬浮体高值区是黄海西部沿岸流物质输运的结果,并与济州岛西南部海域的泥质区总体相对应,黄海与东海的物质交换过程主要通过夏季长江冲淡水东北向扩展与冬半年黄海西部沿岸流南下和黄海暖流北上进行。另外,水体层化和陆架锋也显著影响着南黄海悬浮体的垂直分布状况,锋面是控制夏季悬浮体向外海深水区输运的主要物理机制。 相似文献
20.
白令海楚科奇海的海冰范围变化特征 总被引：3，自引：0，他引：3
白令海和楚科奇海位于北极太平洋一侧的海冰外缘线附近,具有较强烈的气冰海相互作用.采用滑动t检验和小波分析方法对白令海和楚科奇海1953—2004年海冰范围的年际变化、年代际变化和总体趋势变化进行分析.结果表明:20世纪70年代后期,海冰范围在白令海存在显著的均值突变现象,而楚科奇海在对应阶段则表现为更明显的变频现象;在突变点前后两个时段里,阿留申低压中心低压加强、核心位置偏移以及对应风场分布的变化是导致白令海海冰范围明显缩小的主要动力原因.楚科奇海海冰范围的年际变化中存在由低频向高频变化的现象,该现象除了在局地气温变化中存在之外,在北冰洋区域风涡度、波弗特海纬向风、东西伯利亚海经向风等动力因素中也有所体现.因此,除热力因素外,动力因素引起的海冰的平流与该变频现象也存在一定的联系. 相似文献