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自1849年以来,人们就注意到了沿里约格兰德裂谷发生的一系列地震。在1849年到1961年的无地震仪器记录时期,几乎所有地震都是沿裂谷的 Albuquerquc 到 Socorro 的150公里长的地段发生的.但主要是在 Belen 到 Socorro 的75公里长的一段.在此地段上,最显著的地震活动是1906年到1907年的持续时间很长的强地震群。它包括三次中强地震(有感范围125000到24500平方公里).由于1962年开始使用地震仪器,揭示了过去16年裂谷上低水平的地震活动性.平均每年仅有2次 M_L2.4的地震.同时在平原和科罗拉多高原也观测到了类似低水平的地震活动.根据地质资料揭示的两个邻近的自然地理区,在构造上比裂谷稳定得多。由地震仪研究的另一个发现是沿裂谷有一个大的地震空白区。例如从 Socorro 到 Las Cruces,自1962年以来,没发生过 M_L≥2.4的地震。新墨西哥采矿工业学院。Las Alamos 科学实验室和 Albuquerque 地震地质研究窒(U.S.G.S)沿裂谷详细开展的地震研究表明,裂谷内存在着微震活动集中的区域.突出的地段是 Belen到 Socorro 和 Espanola 以西的15公里,这两个地震区可能与中到上部地壳的现代岩浆体有关。LasAlamos 科学实验室研究的一个重要发现是在以破火山口为中心的相当大的区域内缺乏微震活动和在浅部地壳可能有高温显示.裂谷区域微震的合成断层面解表明.在裂谷上普遍存在着走滑断层和正断层,且以后者为主.对于全部断层面解的 T 轴.其平均走向是近乎东西的.沿裂谷空间分布的少量地震表明,在这个时期,裂谷可能没有扩展.在 Socorro 一处的大地测量结果与上述推断相一致.
Since 1849, a series of earthquakes along the Rio Grande Rift have been noticed. During the seismograph-free logging from 1849 to 1961, almost all earthquakes occurred along the 150-kilometer stretch from the rift Albuquerquc to Socorro, but mainly over a 75-kilometer stretch from Belen to Socorro. The most significant seismic activity on the lot is the strong, long-lasting seismic mass from 1906 to 1907. It consists of three moderate to moderate earthquakes (with a range of 125,000 to 24,500 km²), revealing a low level of seismicity over the past 16 years due to the beginning of seismic instruments in 1962. On average, there are only 2 M_L2.4 Earthquakes, while similar low-level earthquakes were also observed in the plains and the Colorado Plateau, and the two adjacent physical geographies revealed by geological data are much more structurally stable than rifts. Another finding from the seismograph study is that there is a large seismic void along the rift. For example, from Socorro to Las Cruces, no earthquake with M_L ≥2.4 occurred since 1962. New Mexico Institute of Mining and Technology. Seismic studies carried out in detail along the rift at the Las Alamos Scientific Laboratory and the Albuquerque Seismo-Geological Research Facility (USGS) show that there is an area of concentrated microseismic activity within the rift that is 15 km west of Belen to Socorro and Espanola The seismic zones may be related to the modern magma in the middle to upper crust. An important finding of the LasAlamos science lab study is the lack of microseismic activity over a large area centered on the caldera and the possible presence of elevated temperatures in the shallow crust. Synthetic fault planes from microseismic solutions in the rift region suggest that in the rift The strike-slip and normal faults are widespread and the latter dominated. The average strike of the T-axis for all fault planes is near-zero. The small number of earthquakes distributed along the rift space suggests that during this period rifts may No extension. The geodetic measurements at Socorro coincide with the above inference.