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421.
Tectonically active sediment dispersal system in SW Taiwan margin with emphasis on the Gaoping (Kaoping) Submarine Canyon 总被引:1,自引:0,他引:1
The sediment dispersal system in southwestern Taiwan margin consists of two main parts: the subaerial drainage basin and the offshore receiving marine basin. In plan view, this sediment dispersal system can be further divided into five geomorphic units: (1) the Gaoping (formerly spelled Kaoping) River drainage basin, (2) the Gaoping (Kaoping) Shelf, (3) the Gaoping (Kaoping) Slope, (4) the Gaoping (Kaoping) Submarine Canyon and (5) the Manila Trench in the northernmost South China Sea. The Gaoping River drainage basin is a small (3250 km2), tectonically active and overfilled foreland basin, receiving sediments derived from the uprising Central Range of Taiwan with a maximum elevation of 3952 m. The Gaoping Submarine Canyon begins at the mouth of the Gaoping River, crosses the narrow Gaoping Shelf (~ 10 km) and the Gaoping Slope, and finally merges into the northern termination of the Manila Trench over a distance of ~ 260 km. The SW Taiwan margin dispersal system is characterized by a direct river-canyon connection with a narrow shelf and frequent episodic sediment discharge events in the canyon head.In a regional source to sink scheme, the Gaoping River drainage basin is the primary source area, the Gaoping Shelf being the sediment bypass zone and the Gaoping Slope being the temporary sink and the Manila Trench being the ultimate sink of the sediment from the Taiwan orogen. It is inferred from seismic data that the outer shelf and upper slope region can be considered as a line source for mass wasting deposits delivered to the lower Gaoping Slope where small depressions between diapiric ridges are partially filled with sediment or are empty.At present, recurrent hyperpycnal flows during the flood seasons are temporarily depositing sediments mainly derived from the Gaoping River in the head of the Gaoping Submarine Canyon. On the decadal and century timescales, sediments temporarily stored in the upper reach are removed over longer timescales probably by downslope-eroding sediment flows within the canyon. Presently, the Gaoping Submarine Canyon serves as the major conduit for transporting terrestrial sediment from the Taiwan orogen to the marine sink of the Manila Trench. Seismic data indicate that the Gaoping Submarine Canyon has been eroding the Gaoping Slope intensely by presumed hyperpycnal flows and transporting sediments from the canyon head to the middle and lower reaches of the canyon. The middle reach is a sediment bypass zone whereas the lower reach serves as either a temporary sediment sink or a sediment conduit, depending on relative prevalence to deposition or erosion during canyon evolution. Contrast differences in channel gradient and travel length between the Gaoping and Amazon sediment dispersal systems suggest that the Gaoping (Kaoping) River-Canyon system is an active sediment dispersal system for transporting terrestrial materials to the deep sea. The fate of the Gaoping River sediment is the northern Manila Trench. 相似文献
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船厂工程是一个复杂的系统工程。船厂的总体规划是多学科、多专业技术知识的综合运用,是船厂基本建设的关键工作。通过参与舜天造船(扬州)有限公司的基本建设,作者认为建设一座具有现代造船模式的新型船厂,选址合理、规划准确、决策果断、定位清晰、抢抓机遇等是决定船厂成功与否的关键要素。 相似文献
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双层开孔消浪板是一种新型消能结构,其结构通过上层开孔板和下层实心板两部分来解决结构的消能问题.文中通过模型试验的方法来验证结构的消能性能,同时,对双层开孔消浪板结构在规则波作用下的消能系数随3个主要影响因子(相对板宽B/L,相对开孔A/A0,波陡H/L)变化的结果进行分析.通过分析和比较消能系数与影响因子之间的相互关系,证明双层开孔消浪板结构具有较好的消能效果. 相似文献
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通过对当前上海部分轨道交通车站防排烟风管防火板使用情况的调研和分析,就防火板凝露滴水问题对其材质进行了剖析,对防火板材质提出了新的技术要求和建议,以确保轨道交通车站电气设备运行环境的安全。 相似文献
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