RUI: Earthquake Induced Slumping and Sediment Liquefaction at the Head of Monterey Canyon

1989年10月17日，洛马普里塔7.1级地震摧毁了莫斯兰丁海洋实验室的建筑。当时的证据表明，事故原因是设施下的沙子液化。在一次巡航中，在实验室附近获得了侧面扫描声纳图像和Uniboom地震记录，人们意识到海底的大规模滑坡在破坏中起了主要作用。一系列的滑塌疤痕和液化沉积物裂片证明了这种滑坡，这表明在蒙特雷峡谷附近的头部方向上有一大片地区的运动。该项目将在证据被冬季风暴掩盖之前研究海底滑坡和相关液化沉积物裂片的证据。一个船载程序将收集滑坡浅层区域的重复侧扫描调查，将之前的侧扫描调查扩展到峡谷的壁，并对沉积物裂片和滑坡进行采样。潜水员将在浅水区进行直接观察，主要目的是确定对底栖生物生态的影响，并与季节周期进行比较。

On 17 October 1989 the buildings of Moss Landing Marine Laboratories were destroyed by the magnitude 7.1 Loma Prieta earthquake. Evidence at the time pointed to liquefaction of the sand under the facility as the cause. After a cruise on which side-scan sonar images and Uniboom seismic records were obatined adjacent the site of the labs it was realized that large scale slumping of the seafloor played a major role in the destruction. That slumping is evidenced by a series of slump scars and liquefaction sediment lobes that indicate movement of a large region in the direction of the nearby head of Monterey Canyon. This project will study the evidence of the submarine slumps and associated liquefaction sediment lobes before the evidence is obscured by winter storms. A shipboard program will collect repetitive side-scan surveys of the shallow areas of slumping, extend the previous side-scan survey to include the walls of the canyon, and sample the sediment lobes and slumps. Direct observations will be made in shallow water by divers primarily for the purpose of establishing the effects on benthic ecology and for comparisions with seasonal cycles.