Collaborative Research: Structural-Petrologic Characterization of the San Andreas Fault in the SAFOD Drill Holes

[04:45 . 27]科学目标是了解在一个活跃的板块边界断层内的变形和地震产生的物理和化学过程。只有对断裂带的构造和地球化学进行彻底的记录，并与其他数据相结合，才有可能全面了解。这一合作努力将在天文台描述圣安德烈亚斯断层的组成、结构和变形机制。从试验井和钻井前两个阶段（2004-2005年）获得的岩心和岩屑观测，以及钻探地点附近断层暴露的样本，将与其他SAFOD研究中提供的地球物理和水文数据相结合，以解决有关断层结构、物理性质和力学的关键问题，并测试地震破裂动力学、能量平衡和断层弱化的假设。工作包括确定断层岩石岩性、裂缝、次级断层、脉和粒度的分布和方向，并针对关键结构进行详细的微观结构、矿物学和地球化学分析。

0454527EvansThe scientific objective of SAFOD is to understand the physical and chemical processes ofdeformation and earthquake generation within an active, plate-bounding fault. Comprehensiveunderstanding will be possible only if the structure and geochemistry of the fault zone arethoroughly documented and integrated with other data. This collaborative effort will characterizethe composition, structure and deformation mechanisms of the San Andreas fault at theObservatory. Observations of core and cuttings from the pilot hole and first two phases of drilling(2004-2005), and of samples from fault exposures near the drill site, will be integrated withgeophysical and hydrologic data presented in other SAFOD studies to address key questionsregarding structure, physical properties and mechanics of the fault, and to test hypotheses ofearthquake rupture dynamics, energy balance, and fault weakening. Work includes determiningfault rock lithology, and distributions and orientations of fractures, secondary faults, veins, andparticle sizes, and targeting key structures for detailed microstructure, mineralogy, andgeochemistry analyses.