New constraints on relative motion between the Pacific Plate and Baja California microplate (Mexico) from GPS measurements
New constraints on relative motion between the Pacific Plate and Baja California microplate (Mexico) from GPS measurements
复制标题
DOI：
10.1111/j.1365-246x.2007.03494.x
复制
发表时间：
2007-09
影响因子：
2.8
通讯作者：
C. Plattner;R. Malservisi;T. Dixon;P. LaFemina;G. Sella;J. Fletcher;F. Suárez‐Vidal
中科院分区：
文献类型：
--
作者：
C. Plattner;R. Malservisi;T. Dixon;P. LaFemina;G. Sella;J. Fletcher;F. Suárez‐Vidal
摘要我们利用GPS数据给出了一个新的下加利福尼亚地表速度场，用来测试这个微板块的刚性，计算它在全球参考系中的运动，确定它相对于北美和太平洋板块的相对运动，并将这些结果与我们对太平洋-北美运动的估计进行比较。由于纳入了南太平洋海平面和气候监测项目的四个站点，太平洋板块运动的确定得到了改进。这些分析表明，下加利福尼亚作为准刚性块体移动，但移动速度较慢，与太平洋板块相对于北美的方向相同。这与下加利福尼亚州西缘(下加利福尼亚州剪切带)的地震活动是一致的，可能反映了圣安德烈亚斯断层和南加州横向山脉的大弯曲造成的太平洋板块东部边缘对运动的阻力。
SUMMARY We present a new surface velocity field for Baja California using GPS data to test the rigidity of this microplate, calculate its motion in a global reference frame, determine its relative motion with respect to the North American and the Pacific plates, and compare those results to our estimate for Pacific‐North America motion. Determination of Pacific Plate motion is improved by the inclusion of four sites from the South Pacific Sea Level and Climate Monitoring Project. These analyses reveal that Baja California moves as a quasi-rigid block but at a slower rate in the same direction, as the Pacific Plate relative to North America. This is consistent with seismic activity along the western edge of Baja California (the Baja California shear zone), and may reflect resistance to motion of the eastern edge of the Pacific Plate caused by the ‘big bend’ of the San Andreas fault and the Transverse Ranges in southern California.