Mass-wasting features on the continental slope of Northwest Europe
Mass-wasting features on the continental slope of Northwest Europe
复制标题
西北欧大陆坡上的大量浪费特征
DOI：
10.1016/0025-3227(87)90005-3
复制
发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
N. Kenyon
中科院分区：
文献类型：
--
作者：
N. Kenyon
使用中程侧扫声纳、格洛丽亚远程侧扫声纳和气枪地震剖面仪对豪猪湾和挪威北方之间的大陆坡进行了勘察，使用这些方法探测到了表明边坡破坏的较大地物。海底峡谷和他们的第二和第三级冲沟被推断为多个边坡失稳的网站。一对200公里长的斜坡平行陡坎，被认为是由于浅旋转断层，和几组斜坡平行滑塌褶皱已被映射。下坡侵蚀形式的规模范围从Storegga幻灯片，其中有一个大约5700立方公里的位移量，海底峡谷，到小幻灯片组，已取代不到1立方公里的沉积物。除了Storegga Slide之外，在57 ° N和67°N之间的大型幻灯片相对较少。控制该地区边坡破坏分布的因素包括与流域的连接、边坡坡度（坡度> 1.5°时破坏较为常见）和沉积速率。在沿大陆坡上部沿着有强等深流的地方，沉积速率较低，深部往往迅速被填满，破坏受到抑制，从表面形态可以推断出对造成这种现象的重力作用过程有一些了解，但对这些地貌的年龄或今后破坏的可能性知之甚少。
A reconnaissance of the continental slope between the Porcupine Seabight and northern Norway was made using a medium-range sidescan sonar, the GLORIA long-range sidescan sonar and an air-gun seismic profiler.Using these methods the larger features indicative of slope failure have been detected. Submarine canyons and their second- and third-order gullies are inferred to be the site of multiple slope failures. A pair of 200 km long slope-parallel scarps, believed to be due to shallow rotational faulting, and several groups of slope-parallel slump folds have been mapped. Downslope-trending erosional forms range in size from the Storegga Slide, which has a displaced volume of about 5700 km3, to submarine canyons, to groups of small slides that have displaced less than 1 km3of sediment. Apart from the Storegga Slide, large slides are relatively scarce between 57 and 67°N. The factors which are believed to control the distribution of slope failures in this region include connection with drainage basins, slope gradient (failures are common where the gradient is > 1.5°) and sedimentation rate. Where there is a strong contour current along the upper continental slope, sedimentation rate is low, deeps tend to be rapidly filled in and failure is inhibited.Some understanding of the gravitational processes responsible can be inferred from the superficial morphology but little is known of the age or potential for future failure of these features.