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901.
Based on the twice-daily marine atmospheric variables which were derived mostly from the weather maps for 18 years period
from 1978 to 1995, the surface heat flux over the East Asian marginal seas was calculated at 0.5°×0.5° grid points twice a
day. The annual mean distribution of the net heat flux shows that the maximum heat loss occurs in the central part of the
Yellow Sea, along the Kuroshio axis and along the west coast of the northern Japanese islands. The area off Vladivostok turned
out to be a heat-losing region, however, on the average, the amount of heat loss is minimum over the study area and the estuary
of the Yangtze River also appears as a region of the minimum heat loss. The seasonal variations of heat flux show that the
period of heat gain is longest in the Yellow Sea, and the maximum heat gain occurs in June. The maximum heat loss occurs in
January over the study area, except the Yellow Sea where the heat loss is maximum in December. The annual mean value of the
net heat flux in the East/Japan Sea is −108 W/m2 which is about twice the value of Hirose et al. (1996) or about 30% higher than Kato and Asai (1983). For the Yellow Sea, it is about −89 W/m2 and it becomes −75 W/m2 in the East China Sea. This increase in values of the net heat flux comes mostly from the turbulent fluxes which are strongly
dependent on the wind speed, which fluctuates largely during the winter season.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
902.
Monthly Variations of Water Masses in the Yellow and East China Seas, November 6, 1998 总被引:4,自引:0,他引:4
The monthly water mass variations in the Yellow Sea and the East China Sea are investigated using over 40 years of historical
temperature and salinity observations via a cluster analysis that incorporates geographical distance and depth separation
in addition to the temperature and salinity. Results delineate monthly variations in the major water masses and provide some
insight into formation mechanisms and intermixing. The major water masses include the Kuroshio-East China Sea water (KE),
the Yellow Sea surface water (YSS) and bottom cold water (YSB), mixed water (MW), and coastal water (CW). The distribution
of the KE water mass reveals the intrusion pattern into the area west of Cheju. A separate mixed water type appears between
the KE water mass and the Yellow Sea water masses during winter. The formation mechanism of the YSB appears to be the surface
cooling and active mixing in winter. In the East China Sea, during summer, surface water is differentiated from the subsurface
water while there is no differentiation during winter. In the Yellow Sea, a three layer system exists in the summer and fall
(May–November) while a two layer system exists during the rest of the year. A fresh water mass generated by Yangtze River
discharge (YD) is present over the northern East China Sea and the southern Yellow Sea during summer.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
903.
东海南部黑潮区春季温盐度垂直分布类型及其逆现象成因的初步分析 总被引:3,自引:1,他引:2
用1988~1996年在东海南部黑潮区共5个航次的春季水文观测资料,分析了该海区温、盐度垂直分布类型的地理分布,讨论了春季温、盐度逆转现象的形成原因。这主要是春季季风已转变为南风,在南风的驱动下,迫使表层水离岸向东向外海扩张,台湾暖流向北伸展,黑潮次表层水的向岸入侵的结果 相似文献
904.
1994 年 4~11 月在东太平洋铁锰结核区, 使用 “向阳红 09”船, 采集 39 个表层沉积物、12 个上覆水和 7 个结核样。在现场用平板法测定了异养细菌和铁、锰细菌丰度, 用稀释法( M P N 法) 测定硫酸还原菌丰度。为了探讨微生物在大洋成矿过程的作用, 在实验室对异养细菌和锰细菌作纯化分离, 并进行了多项生理生化实验, 参照伯杰氏手册第八版鉴定至属。使用分光光度法, 测定锰细菌对锰、铁离子的转化作用, 使用 p H 计测定了p H 值的变化, 同时测定了不同培养温度对转化作用的影响。结果表明, 沉积物中异养细菌的数量在 3×100~95×103个/g; 锰、铁细菌的数量在1×100 ~1×103 个/g; 硫酸盐还原细菌的数量分布范围在 0~4×103个/g;在上覆水和结核样中各类细菌的数量均较低,比沉积物样中各类细菌数低 1 个数量级。在细菌的种群组成方面与近海区相比存在差异, 特别是在革兰氏阳性菌的组成上微球菌占了绝对优势。在成矿作用方面, 锰细菌对锰、铁氧化还原的实验结果表明, 在好氧的条件下, 锰细菌使可溶性的 M n2+ 氧化为 M n4+ , 其氧化速度与环境温度存在密切关系, 锰细菌对铁的氧化速度比对锰的氧化速度来得快。在 相似文献
905.
东海陆架北部泥质区沉积动力过程的季节性变化 总被引:4,自引:0,他引:4
利用东海陆架北部泥质区(济州岛西南)及其周围不同季节5个航次的悬浮体资料和相应的底质粒度资料,对该泥质区沉积动力过程的季节性变化规律进行了分析。结果表明:东海陆架北部悬浮体的高含量区并不与该区的沉积中心(泥质区)相吻合,泥质区的形成需有物源的充沛供应和涡旋的动力效应相结合。泥质区沉积作用时空变化具有强烈的季节性。冬季泥质区悬浮体供应充足,涡旋中心向泥质区东南扩展,是本区接受悬浮体沉积的关键季节。夏、秋二季泥质区的大部分区域缺少悬浮体物源,涡旋中心向北退缩,致使泥质区沉积作用强度降低,并且主要影响泥质区的西北区域。春季泥质区沉积作用强度和影响范围大于夏、秋两季,但小于冬季。 相似文献
906.
907.
Jinshui Liu Shuai Li Kaifei Liao Yuchi Cui Lei Shao Peijun Qiao Yi Lu Yuanli Hou Thian Lai Goh Yongjian Yao 《海洋学报(英文版)》2023,42(3):89-100
Both Pinghu and Huagang formations are important hydrocarbon reservoirs of the Xihu Depression in the East China Sea Shelf Basin. Clarifying the source suppliers and restoring source-to-sink transport routes are of great significance to the future petroleum and gas undertakings. Previous researchers were largely confined by either limitation of geological records, highly dependence on a singular method or low-precision dating techniques. Our study integrated heavy mineral assemblages, geochemica... 相似文献
908.
Early Cenozoic paleontological assemblages and provenance evolution of the Lishui Sag,East China Sea
Yingzhao Zhang Yiming Jiang Zhenghua Liu Shuai Li Ning Li Jinshui Liu Peijun Qiao Kai Zhong Shuhui Chen Thian Lai Goh 《海洋学报(英文版)》2023,42(3):113-122
The East China Sea Shelf Basin generated a series of back-arc basins with thick successions of marine- and terrestrial-facies sediments during Cenozoic. It is enriched with abundant oil and gas resources and is of great significance to the petroleum exploration undertakings. Therein, the Lishui Sag formed fan delta, fluvial delta and littoral-to-neritic facies sediments during Paleocene–Eocene, and the research on its sedimentary environment and sediment source was controversial. This study analyzed the paleontological combination characteristics, and conducted a source-to-sink comparative analysis to restore the sedimentary environment and provenance evolution of the Lishui Sag during Paleocene–Eocene based on the integration of detrital zircon U-Pb age spectra patterns with paleontological assemblages. The results indicated that Lishui Sag was dominated by littoral and neritic-facies environment during time corroborated by large abundance of foraminifera, calcareous nannofossils and dinoflagellates. Chronological analysis of detrital zircon U-Pb revealed that there were significant differences in sediment sources between the east and west area of the Lishui Sag. The western area was featured by deeper water depths in the Paleocene–Eocene, and the sediment was characterized by a single Yanshanian peak of zircon U-Pb age spectra, and mainly influenced from Yanshanian magmatic rocks of South China Coast and the surrounding paleo-uplifts. However, its eastern area partly showed Indosinian populations. In particular, the upper Eocene Wenzhou sediments were featured by increasingly plentiful Precambrian zircons in addition to the large Indosinian-Yanshanian peaks, indicating a possible impact from the Yushan Low Uplift to the east. Therefore, it is likely that the eastern Lishui Sag generated large river systems as well as deltas during time. Due to the Yuquan Movement, the Lishui Sag experienced uplifting and exhumation in the late stage of the late Eocene and was not deposited with sediments until Miocene. Featured by transitional-facies depositions of Paleocene–Eocene, the Lishui Sag thus beared significant potential for source rock and oil-gas reservoir accumulation. 相似文献
909.
Yanpei Zhuang Yangjie Li Xizhen Liu Shichao Tian Bin Wang Zhongqiang Ji Haiyan Jin Jianfang Chen 《海洋学报(英文版)》2023,42(1):103-108
Here, we report the results of high-resolution nitrate measurements using an optical nitrate profiler(in situ ultraviolet spectrophotometer, ISUS) along transect across a high-turbidity shelf(East China Sea) and a lowturbidity shelf(Chukchi Sea). The ISUS-measured nitrate concentrations closely reproduced the results measured by conventional bottle methods in low-turbidity waters. However, for high-turbidity waters of the East China Sea(salinity<30), a correction factor of 1.19 was required t... 相似文献
910.
东太湖的环境质量现状调查评价 总被引:7,自引:2,他引:5
通过1990—1991年东太湖的水文、水质、底质和生物凋查,对其水质作出评价并探求营养现状。结果表明:东太湖的水质状况良好,营养状况已进入中富营养状态叶。 相似文献