Collaborative Research: Collection of Marine Geophysical Data on Transits of the Nathaniel B. Palmer

本项目将使用R/VI B Nathaniel B。帕尔默的过境巡航收集南大洋目标的海洋地球物理数据。由于帕尔默号通常只穿越地球物理仪器很少勘测的地区，因此该项目是收集重要新数据的一种具有成本效益的方式。这项工作的重点是扩大我们对南极洲和周围板块运动历史的了解。最终目标是改善全球板块重建，并获得新的见解一般板块运动学和动力学和岩石圈流变学。只需要稍微偏离直线航线，我们预计在该项目的三年内每年运营一次游轮。从新西兰到智利的第一次巡航将沿着梅纳尔断裂带调查太平洋-南极板块运动的流线，该断裂带在南纬50度处穿过东太平洋隆起。将收集条带测深、重力、磁力和少量地震反射剖面图，以确定断裂带的确切轨迹及其与船上和卫星雷达测高数据中所见的相关重力异常的关系。这些观测结果对于精确的板块重建至关重要，并将提供太平洋-南极边界北方端附近一个主要断裂带的GPS导航位置。这些数据将与来自板块边界西南端皮特曼断裂带的类似数据和以前在梅纳尔断裂带附近进行的考察获得的磁异常数据结合使用，以改进高精度的板块重建，并评价太平洋和南极板块内部变形的极限。一旦确定了过境时间表，将设计接下来几年的游轮科学计划。就更广泛的影响而言，我们计划在两次巡航中为研究生和本科生开设船上海洋生物物理学课程。该课程包括关于仪器和数据的日常课堂讲座;每天几个小时的手表站立和数据处理;以及每个学生独立研究项目的工作。我们预计每班可容纳15名学生，包括来自少数民族入学率高的主要本科院校的参与者。

This project will utilize the R/VIB Nathaniel B. Palmer's transit cruises to collect marine geophysical data on targets-of-opportunity in the southern oceans. Because the Palmer generally traverses regions only sparsely surveyed with geophysical instruments, this project represents a cost-effective way to collect important new data. The work's focus is expanding our knowledge of plate motion histories for the Antarctic and surrounding plates. The ultimate goals are improving global plate reconstructions and gaining new insight into general plate kinematics and dynamics and lithospheric rheology. Only slight deviations from the straight routes are required, and we expect to operate on one cruise per year over the three years of the project. The first cruise from New Zealand to Chile will survey a flow line of Pacific-Antarctic plate motion along the Menard fracture zone, which crosses the East Pacific Rise at ~50 S latitude. Swath bathymetry, gravity, magnetics, and a small amount of seismic reflection profiling will be collected to determine the exact trace of the fracture zone and its relationship to the associated gravity anomaly seen in shipboard and satellite radar altimetry data. These observations are critical for precise plate reconstructions, and will provide GPS-navigated locations of a major fracture zone near the northern end of the Pacific-Antarctic boundary. These data will be used in combination with similar data from the Pitman fracture zone at the southwestern end of the plate boundary and magnetic anomalies from previous cruises near the Menard fracture zone to improve high-precision plate reconstructions and evaluate the limits of internal deformation of the Pacific and Antarctic plates. The science plan for cruises in following years will be designed once transit schedules are set. In terms of broader impacts, we plan to teach an on-board marine geophysics class to graduate and undergraduate students on two cruises. The class consists of daily classroom lectures about the instruments and data; several hours per day of watch standing and data processing; and work by each student on an independent research project. We expect to accommodate 15 students per class, including participants from primarily undergraduate institutions with high minority enrollments.