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

1989 年 10 月 17 日，莫斯兰丁海洋实验室的建筑物被 7.1 级洛马普列塔地震摧毁。 当时的证据表明，设施下方的沙子液化是原因。 在实验室附近获得侧扫声纳图像和 Uniboom 地震记录的巡航之后，人们意识到海底的大规模塌陷在破坏中发挥了重要作用。 一系列塌陷疤痕和液化沉积物叶证明了这种塌陷，表明大片区域正在向蒙特利峡谷附近的头部方向移动。 该项目将在证据被冬季风暴掩盖之前研究海底塌陷和相关液化沉积物叶的证据。 船上计划将收集塌陷浅层区域的重复侧扫描调查，将之前的侧扫描调查扩展到包括峡谷壁，并对沉积物瓣和塌陷进行采样。 潜水员将在浅水中进行直接观察，主要目的是确定对底栖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.