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大陆坡的定义是从陆架坡折向外延伸并终止于陆隆的地带。在陆隆处,海底坡度变得小于1:40,或者,陆坡在那里与深海沟或边缘台地相邻接。虽然陆坡通常是大陆边缘最陡的地貌单元,但也不能就此而得出一个唯一的,简单化的定义。大陆坡的宽度在20到100公里之间,在陆架坡折处的上界一般开始于水深100米至200处米;它的下界在1,400米到3,200米以上的水深范围内。陆坡区可以是平坦的,或阶地式的,可能具有陡立的悬崖或坡内盆地;或者由于有滑坡,断层崖或底辟而很不规则。多数陆坡在其上部很多地方被与深海扇相接的水下峡谷横切,这些深海冲积扇在下部陆坡、陆隆、海沟和部分深海平原上形成了增生性的沉积体。因为陆坡既位于活动的、又位于被动的构造背景内,所以海底扩张和板块构造的概念对解释陆坡演化是很重要的。沉积物的向上或向外堆积、滑坡和滑移,海平面升降的影响、以及礁相建造或盐的构造作用造成了与仅仅由俯冲作用和板块加积作用而形成的不同的陆坡。不过,一些活动边缘背景内的加积盆地与在被动边缘背景内一样可能具有丰富的沉积物堆积。作为陆架和深海之间的过渡带,出于科学、经济及政治上的原因,大陆坡构成海底研究的一个重要部分。不同的大地构造史及沉积史产生了各种沉积组合及地貌,在一些地区,这些因素综合产生了有利于商业数量的油气以及经过分选的固体矿物聚积的条件。
The continental slope is defined as a zone extending from the continental slope and terminating in Luolong. At the longhorn, the submarine gradient becomes less than 1:40, or where the slope adjoins a deep trench or margin platform. Although slopes are usually the steepest geomorphic units on the continental margin, no single, simplistic definition can be drawn for this purpose. The continental slope is between 20 and 100 kilometers in width. The upper boundary of the slope at the shelf generally begins at a water depth of 100 to 200 meters; its lower bound is in the water depth of 1,400 to 3,200 meters. The slope region may be flat or terrace type, may have steep cliffs or in-slope basins, or may be irregular due to landslides, faulty cliffs or diapirs. Most of the slopes are traversed in subterranean canyons by deep-sea fans in many parts of their upper reaches. These deep-sea alluvial fans form accretionary sediments on the lower slopes, the Lu Long, the trench, and parts of the deep-sea plains. Because continental slopes are both active and passive, the concept of submarine expansion and plate tectonics is important for interpreting continental evolution. The upward or outward accumulation of sediments, landslides and slippages, the effects of sea-level rise and fall, and the reef facies or the tectonism of the salt have resulted in different slopes formed by subduction and plate addition alone. However, the accretion basin within some active margin backgrounds may have the same accumulation of sediments as in the passive margin background. As a transitional zone between the shelf and the deep sea, continental slopes form an important part of seabed research for scientific, economic and political reasons. Various tectonism and sedimentary history have resulted in various sedimentary assemblages and topographies that in some areas have resulted in conditions conducive to commercial quantities of oil and gas and the accumulation of sorted solid minerals.