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961.
Sea level data measured by TOPEX/POSEIDON over the Japan Sea from 1993 to 1994 is analyzed by assimilation using an approximate Kalman filter with a 1.5 layer (reduced-gravity) shallow water model. The study aims to extract signals associated with the first baroclinic mode and to determine the extent of its significance. The assimilation dramatically improves the model south of the Polar Front where as much as 20 cm2 of the observed sea level variance can be accounted for. In comparison, little variability in the northern cold water region is found consistent with the model dynamics, possibly due to significant differences in stratification. 相似文献
962.
Intermediate Waters in the East/Japan Sea 总被引:4,自引:0,他引:4
Properties of the intermediate layer in the East/Japan Sea are examined by using CREAMS data taken mainly in summer of 1995.
Vertical profiles of potential temperature, salinity and dissolved oxygen and relationships between these physical and chemical
properties show that the dissolved oxygen concentration of 250 μmol/l, roughly corresponding to 0.6°C at the depth of about
400 db, makes a boundary between intermediate and deep waters. Water colder than 0.6°C has a very stable relationship between
potential temperature and salinity while salinity of the water warmer than 0.6°C is lower in the western Japan Basin than
that in the eastern Japan Basin. The low salinity water with high oxygen corresponds to the East Sea Intermediate Water (ESIW;
<34.06 psu, >250 μmol/l and >1.0°C) which was previously identified by Kim and Chung (1984) and the high salinity water with
high oxygen found in eastern Japan Basin is named as the High Salinity Intermediate Water (HSIW; >34.07 psu, >250 μmol/l and
>0.6°C). Spatial distribution of salinity and acceleration potential on the surface of σϑ = 27.2 kg/m3 shows that the ESIW prevailing in the western Japan Basin is transported eastward by a zonal flow along the polar front near
40°N and a cyclonic gyre in the eastern Japan Basin is closely related to the HSIW.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
963.
中,日渔业法规比较研究 总被引:1,自引:0,他引:1
中日两国有不同的国情和社会制度,造成两国的渔业法规必然存在差异。但是两国的渔业资源和捕捞海域有相近之处,渔业法规也应有类似的内容。由于日本渔业法规制定较早,立法体系较完备;而我国渔业法规起步较晚,立法体系较简单。本文通过对中、日两国渔业法规进行比较,从日本渔业法规中找到可供我国借鉴的地方。 相似文献
964.
965.
Syntheses of the regional stress fields of the Japanese islands 总被引:4,自引:0,他引:4
Tetsuzo Seno 《Island Arc》1999,8(1):66-79
The principal stresses in northern Honshu and in central-southwest Japan are synthesized on the basis of the ridge push, slab pull and across-arc variation of differential forces due to crust/plate structural variation. Assuming a more compressive north–south horizontal stress in central Japan-northern Honshu than that of southwest Japan, the calculated principal stress profiles explain the observed stress fields in these areas: namely, a strike–slip fault type for southwest-central Japan and a reverse fault type for northern Honshu, both having east–west σHmax . Kyushu is characterized by the gradient of horizontal stresses both in the east–west and north–south directions, which cannot be explained by simple plate interactions or by crust/plate structural variation. Combined with other lines of evidence for existence of mantle upwelling in the East China Sea west of Kyushu, it is proposed that the stress gradient is produced by the viscous drag exerted by the flow spread laterally from the upwelling plume. The eastward movement of Kyushu and southwest Japan relative to Eurasia revealed by the recent Global Positioning System measurements conducted by the Geographical Survey Institute of Japan would be partly explained by this basal drag. 相似文献
966.
The hemipelagic mudrocks of the Nankai accretionary prism, Japan, contain hydrothermal deposits associated with a relict spreading center in the Shikoku Basin. Initial work on core samples from Ocean Drilling Program site 808 found several samples with elevated concentrations of calcium, magnesium, iron and manganese, at depths of between 1060 and 1111 m below sea floor. However, the origin of these sediments was uncertain, due to a lack of data. There was no recorded evidence of whether these elevated concentrations were present throughout this interval of core, or if they were present as discrete layers with the background hemipelagic mudrocks in between. In the present study the core was resampled, and the sediments with anomalous chemical compositions were found to be present in discrete layers. This fact, along with a detailed interpretation of their geochemistry, has allowed them to be identified as hydrothermal sediments, associated with the relict spreading center in the Shikoku Basin. The lower (older) two layers display a chemical composition typical of umbers, while the upper (younger) two layers are metalliferous mudrocks typical of deposits found further from the spreading center. 相似文献
967.
Abstract In Japan and Korea, some Lower Cretaceous terrigenous clastic rocks yield detrital chromian spinels. These chromian spinels are divided into two groups: low-Ti and high-Ti. The Sanchu Group and the Yuno Formation in Japan have both groups, whereas the Nagashiba Formation in Japan and the Jinju Formation in Korea have only the low-Ti spinels. High-Ti spinels are thought to have originated in intraplate-type basalt. Low-Ti spinels (higher than 0.6 Cr#) were probably derived from peridotites, which are highly correlated with an arc setting derivation and possibly with a forearc setting derivation. Low-Ti spinels are seen in the Sanchu Group, the Nagashiba Formation and the Jinju Formation. Low-Ti spinels from the Yuno Formation are characterized by low Cr# (less than 0.6) and these chromian spinels appear to have been derived from oceanic mantle-type peridotite, including backarc. According to maps reconstructing the pre-Sea of Japan configuration of the Japanese Islands and the Korean Peninsula, the Korean Cretaceous basin was comparatively close to the Southwest Japan depositional basins. It is possible that these Lower Cretaceous systems were sediments mainly in the forearc and partly in the backarc regions. The peridotite might have infiltrated along major tectonic zones such as the Kurosegawa Tectonic Zone (= serpentinite melange zone) in which left lateral movement prevailed during the Early Cretaceous. 相似文献
968.
产业集群与日本区域经济发展及其对中国东北区的启示 总被引:6,自引:4,他引:2
分析了日本区域经济发展的基本态势,得出日本区域经济仍具有非均衡发展的特点,用传统经济地理学对日本区域经济非均衡发展作出了解释;然后运用新经济地理学的产业集群理论,分析了日本产业集群的发展特点,探讨了产业集群的发展机制,提出了日本产业集群的发展状况与区域经济非均衡发展关系十分密切的结论。最后,从培育产业集群的角度,探讨了促进中国东北区产业集群发展,推动东北区区域经济发展的途径。 相似文献
969.
基于GIS的粮食生产安全预警研究——以东北三省为例 总被引:1,自引:0,他引:1
本文借鉴国内外有关预警理论和实践的最新成果,对粮食生产安全预警的基本方法进行了探讨,建立了基于全国的区域粮食生产安全预警模型,并以东北三省为例,借助GIS进行实证研究。研究结果表明,吉林和辽宁两省2000年粮食生产安全程度低于2003年,而黑龙江省则相反,2000年的粮食生产安全程度则高于2003年,这与东北地区粮食生产实际状况相符,表明该模型可以较客观地反映区域粮食生产状况。文章最后根据模型对东北地区2010年的粮食生产安全进行了预测。 相似文献
970.