The importance of clay mineral reactions on the seismic behavior of the San Andreas Fault: Part 2-Hydration states and timing of mineralization

粘土矿物反应对圣安德烈亚斯断层地震行为的重要性：第 2 部分 - 水化状态和矿化时间

• 批准号: 22073701
• 负责人: Dr. Anja Schleicher
• 金额: --
• 依托单位: Sektion 3.1: Anorganische und Isotopengeochemie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/22073701?language=en
• 关键词: importance; clay; mineral; reactions; seismic

The San Andreas Fault Observatory at Depth (SAFOD) main hole, drilled in Parkfield, California, USA, provides a unique opportunity to study the nature of clay-rich samples collected at depth from an active fault System and to assess their contribution to controlling seismogenic and creeping behavior. During 2005, fresh rock chips were collected from a core and impregnated onsite using low viscosity polymer-based resins. In the first year of research, samples were characterized using high resolution microscopy and X-ray diffractometry. In the second year, the interlayer hydration state will be determined along with the original clay mineral textures. Quantifying the amount of water adsorbed on surface and interlayer sites at circa 3 km depth is critical for understanding the role of swelling clays in the faulting process. Additionally, 40Ar/39Ar dating of fault-related neocrystallized illitic minerals on key fault planes will be used to constrain the timing of mineralization in this fault System. The study will include collection and study of new sample material that will become available during the scheduled 2007 site coring activities.

在美国加州帕克菲尔德钻探的圣安德烈亚斯断层深度观测（SAFOD）主孔提供了一个独特的机会，可以研究从活动断层系统深处采集的富含粘土的样品的性质，并评估它们对控制孕震和蠕动行为的贡献。2005年期间，从岩芯中收集了新鲜的岩屑，并使用低粘度聚合物基树脂进行现场浸渍。在研究的第一年，使用高分辨率显微镜和X射线衍射法对样本进行了表征。在第二年，将沿着原始粘土矿物结构确定层间水化状态。定量的水吸附在表面和层间网站在约3公里的深度是了解的作用，在断层过程中的膨胀粘土的关键。此外，40 Ar/39 Ar测年的断层相关的新生伊利石矿物的关键断层面将被用来限制在该断裂系统的成矿时间。这项研究将包括收集和研究新的样品材料，这些材料将在预定的2007年现场取芯活动期间提供。