GPS Geodesy in the California Borderlands

作为阐明在加利福尼亚的北美/太平洋板块边界如何分布变形的一系列努力的一部分，PI将继续在加利福尼亚南部近海的大陆边界地区进行GPS调查。自1986年以来，这类调查一直由包括加州大学圣地亚哥分校在内的四所大学组成的联盟进行。各种证据表明，该地区目前存在变形，可能有20%的板块边界运动发生在那里。到目前为止所做的调查对该地区给出了一些初步结果，但也提出了新的问题。这些调查的跨度（5年）还不足以明确地确定变形模式。这个项目将使观测时间延长一倍；考虑到过去几年卫星星座和跟踪网络的改进，这应该能将误差减少一半以上。由于进行这些测量的一个主要原因是完全了解板块在这一边界上的运动预算，因此需要使误差小于剩余的未知运动量。这还不是真的，但当这些测量完成后应该是真的。

As part of a number of efforts to elucidate how deformation is distributed across the North-American/Pacific plate boundary in California, the PI will continue GPS surveys in the Continental Borderland region, offshore of southern California. Such surveys have been conducted since 1986 by a consortium of four universities, including UCSD. A variety of evidence suggests that there is currently deformation in this region, with perhaps 20% of the total plate-boundary motion occurring there. The surveys so far made have given a number of tentative results for this region, but have raised new questions as well. The span of these surveys (5 years) has not been sufficient to unequivocally determine the deformation patterns. This project will double the time span of observations; given the improvements in the satellite constellation and tracking networks that have taken place in the last few years, this should do better than halve the errors. Since a major reason for making these measurements at all is to understand completely the budget of plate motion across this boundary, the needs to make the errors smaller than the remaining unknown amounts of motion. This not yet true, but should be when these measurements are complete.