Collaborative Research: Permanent seafloor benchmarks for geodetic measurements of horizontal and vertical plate motion

国际海底测量局要求提供资金，通过开发和展示一种廉价的永久性海底基准来延长海底大地测量的寿命。该基准将提供与海底持续数十年(可能更长)的物理联系，在海底上可以重复放置和移除以毫米分辨率进行的大地测量传感器。用海底大地测量技术估计的全球坐标将继续与基准相关联，以便在传感器失效或过时时更换传感器，或将传感器移走并在其他地方使用，同时始终保持参照基准的一系列连贯的位置。基准将被设计为通过连接传感器的电线降低到海底。这些传感器将能够通过从船上发出的声学命令被召回，以从基准释放并自由漂浮到海面上进行回收。传感器连接到基准的持续时间将从几天到几年不等，具体取决于实验的具体需求。回收的传感器随后可以在其他地点重复使用，或者未来在同一地点再次使用。广泛的影响：如果能够开发出高精度、廉价的运动式海底大地测量，可以用这样的系统进行的研究可能会改变我们对俯冲带和大地震的知识。

The PI's request funding to increase the longevity of seafloor geodetic measurements by developing and demonstrating an inexpensive, permanent seafloor benchmark. The benchmark will provide a physical tie to the sea floor lasting for decades (perhaps longer) on which geodetic sensors can be repeatedly placed and removed with millimeter resolution. Global coordinates estimated with seafloor geodetic techniques will remain attached to the benchmark allowing for the interchange of sensors as they fail or become obsolete, or for the sensors to be removed and used elsewhere, all the while maintaining a coherent series of positions referenced to the benchmark. The benchmark will be designed to be lowered via a wire to the seafloor with sensors attached. The sensors will be capable of being recalled via an acoustic command sent from a ship to release from the benchmark and freely float to the sea surface for recovery. The duration of the sensor attachment to the benchmark will last from a few days to a few years depending on the specific needs of the experiment. The recovered sensors are then available to be reused at other locations, or again at the same site in the future.Broader Impacts:If high accuracy, cheap, campaign-style seafloor geodesy can be developed, the studies that could be done with such a system could transform our knowledge of subduction zones and megathrust earthquakes.