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1.
根据最新调查获得的北黄海盆地海洋重力、海洋与航空磁力和多道地震资料,结合以往周边地区的资料,编制了北黄海空间重力异常图、布格重力异常图、磁力异常图。在重磁基础图件的基础上,通过解析延拓、任意方向导数计算、离散小波变换等处理,结合地震和地质资料,对北黄海北缘断裂带进行了综合分析。确定了北黄海北缘断裂带的存在,并对该断裂带的延伸长度、切割深度和性质进行了分析,指出北黄海北缘断裂带是辽东隆起与北黄海盆地的界线,断裂带两侧具有明显不同的地球物理场特征;而且断裂带具有多期活动的特点,对北黄海盆地的形成演化具有重要的控制作用。 相似文献
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近江牡蛎作为重金属污染生物指示种的初步研究 总被引:17,自引:2,他引:17
对近江牡砺作为监测广东岸海域Cu,Zn,Cd,Pb污染的生物指示种的可能性进行了初步研究和评价,应用POLYDIV统计技术对采自广东沿岩海域14个站点的近江牡盛的重金属含量进行了统计分析,结果表明近江牡蛎受Cu,Zn,Cd污染的地理分布类型与广东沿海排放的工业废水的分布以及潮间带生物和表层沉积物的Cu,Zn,Cd含量分布相一致,因此,近江牡蛎可作为监测研究Cu,Zn,Cd污染的可靠生物指示种,但能 相似文献
3.
漳州地区热田的水热活动及其成因 总被引:1,自引:0,他引:1
本文通过漳州地热田及其周围地区的水热活动、地质构造特征及人工爆破、重力、地磁、电性结构、地震活动性等综合地球物理场之间关系分析,得出漳州地热田是高热异常背景下产生的对流型水热系统:深切到上地幔的NE向长乐-南澳断裂、NW向九龙江断裂及E-W向南靖-厦门断裂控制了地下水的深循环,使大气降水得以下渗到〉3km深度,被地温加热并富集起来,在静水压力作用下沿通道-断裂带的交汇部位上涌。热田区破碎的岩石导致 相似文献
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Viability theory for an ecosystem approach to fisheries 总被引:1,自引:1,他引:1
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在系统开展海洋区域地质调查的过程中,荷兰广泛使用了各种地球物理调查方法,并在方法选用、测线部署、资料处理和图件编制等方面有许多独到之处;对中荷两国的做法进行了系统的比较;对今后在我国海洋区域地质调查中如何开展地球物理调查工作提出了建议。 相似文献
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Bathymetric, gravity, and magnetic data from Antarctic expeditions with RV POLARSTERN and satellite altimeter data from the Geosat Geodetic Mission are analysed using methods from geostatistics and geophysical inverse theory.The Explora Escarpment represents the edge between the Antarctic Continental Shelf and the Weddell Abyssal Plain. It is an important link in the reconstruction of Gondwana breakup, but a feature as large as the 2000 m deep Wegener Canyon was only discovered in 1984, when extensive bathymetric, gravimetric, and magnetic surveys with RV POLARSTERN began.Geostatistics, the theory of regionalized variables, is applied to integrate dense surveys of Wegener Canyon and sparse observations in adjacent areas into maps with full coverage of the 230 km by 330 km area at 10°–20° W/70°–72° S. The resultant highresolution bathymetric and gravity maps reveal detailed structures of the Explora Escarpment. Using geophysical inversion, the gravity terrain effect is calculated. Satellite data are used for their better coverage, but have much lower resolution. Nevertheless, the structures of Wegener Canyon and other more prominent features appear with surprisingly good correlation also in the Geosat altimeter data. While it was initially supposed that Wegener Canyon is purely an erosional structure, the magnetic map now provides evidence of the canyon's tectonic origin. 相似文献
10.
Hueiwang Anna C. Jeng Andrew J. Englande Reda M. Bakeer Henry B. Bradford 《Estuarine, Coastal and Shelf Science》2005,63(4):513-526
Urban stormwater runoff could contribute to the deterioration of water quality of a receiving water body. In this research, field studies and laboratory experiments were conducted to assess the microbial contamination resulting from urban stormwater runoff into the Lake Pontchartrain estuary. Fecal coliform, Escherichia coli and enterococci were used as indicator organisms. The specific objectives of the research were to examine the distribution of the indicator organisms in different environmental elements (water column, suspended particles and sediment) and to further investigate the mechanisms related to their fate. Results of the research indicated satisfactory water quality at the study sites during dry weather periods. However, a significant increase was observed in the concentrations of the indicator organisms in the water columns and sediment at specific study sites following a given stormwater event. Three to seven days were needed for the elevated indicator organisms to return back to their background levels in the water column and sediment, respectively. The mechanism of sedimentation contributed to a reduction in the microbial concentration in the water column, as the indicator organisms were found to attach to the suspended particles in the stormwater. The percentage of fecal coliform, E. coli and enterococci attached to the suspended particles was found to be within the range of 9.8–27.5%, 21.8–30.4%, and 8.4–11.5% of the total indicator organisms in the stormwater loaded into the estuary, respectively. About 75–80% of the total indicator organisms remained free-floating for some distance in the water column before dying off. 相似文献