Collaborative Research: San Andreas Scientific Drilling Project - Seismic Imaging of the San Andreas Fault at Parkfield, California

[9814192 . thurber]这个奖项是在圣安德烈亚斯断层钻一个4公里深的洞的综合建议的一部分。该钻探地点靠近1966年帕克菲尔德M~6级地震的震源，在那里，圣安德烈亚斯断层通过中小地震和地震蠕变的组合滑动。该项目涉及来自美国和国外的约100名科学家，将与美国地质调查局（USGS）、美国能源部（DoE）和外国机构合作进行。这个特殊的项目涵盖了Parkfield的两部分合作和钻井前断层带表征项目的一半。这两个综合的钻井前项目是获取数据的关键路径活动，这些数据将定义许多井下实验计划。该项目的目标有两个：以足够的准确度和精度确定钻井目标地震的绝对位置，以确保第二阶段钻井的成功，并在断裂带钻井目标体积中确定小尺度（M0，重复时间为几周到几个月）的微地震活动的系统性（时空震级）。拟议的协作工作包括(a)重新分析现有地震数据，(b)运行15个台站的地面“校准”地震阵列，(c)在钻井现场附近安装3个新的钻孔站，以及(d)协作分析来自新工作的数据。这些信息将用于确定钻孔计划和工程规范，并优化在活动断裂带进行的实验。***

9814192ThurberThis award is one component of a comprehensive proposal to drill a 4-km deep hole into the San Andreas fault. The drill site is close to the hypocenter of the 1966 M~6 Parkfield earthquake, where the San Andreas fault slips through a combination of small-to-moderate earthquakes and aseismic creep. The project involves about 100 scientists from the U.S. and abroad and would be conducted in collaboration with the U.S. Geological Survey (USGS), the U.S. Department of Energy (DoE) and foreign institutions. This particular project covers half of a two-part cooperative and collaborative pre-drilling fault-zone characterization program at Parkfield. These two integrated pre-drilling projects are critical-path activities to acquire data that will define much of the downhole experimental program. The goals of the project are twofold: to determine the absolute locations of the drilling target earthquakes with sufficient accuracy and precision to assure a successful second stage of drilling, and to define systematics (space-time-magnitude) in microseismicity at small-scale (M0, recurrence times of weeks to months) in the drilling target volume of the fault zone. The proposed collaborative work involves (a) reanalysis of existing seismic data, (b) operation of a 15-station surface "calibration" seismic array, (c) installation of 3 new borehole stations near the drilling site, and (d) collaborative analysis of data from the new efforts. This information will be used to determine the drilling plan and engineering specifications for the hole, and to optimize the experiments to be conducted in the active fault zone.***