New Heat Flow Values Along the San Andreas Fault System

犹他州大学的调查人员将与弗朗西斯科湾区的美国地质调查局一起沿着圣安德烈亚斯、海沃德和卡拉维拉斯断层进行热调查。将在目前计划钻探的钻孔中收集热测量值，作为“迷你板边界观测站”实验的一部分，以安置钻孔应变计。研究的实地部分包括热测井和收集钻屑和岩石样品，以确定岩石的热物理性质。将使用现代实验室技术测量岩石的热物理性质。这些钻孔将随着时间的推移重新记录，以研究热瞬变（例如，流体流动、地表温度变化、与断层有关的热事件）。该项目的建模部分旨在解决：1）热传递的性质和热流沿着这一复杂的板块边界的变化; 2）在地震活动的下限和上限的热条件;和3）热变形瞬变的影响，确定从大地测量数据和粘弹性变形模型。现场区域是拟议工作的理想选择，因为旧金山弗朗西斯科湾区具有相对较高的热流（~85 mW m-2）和高应变率。这两个属性最大限度地增加了调查地壳热状况和地壳瞬变之间关系的机会。

EAR-00877577Harris, RobertThe investigators at University of Utah will conduct a thermal investigation with the U.S.G.S of the San Francisco Bay Area along the San Andreas, Hayward and Calaveras faults. Thermal measurements will be collected in boreholes currently scheduled for drilling as part of the 'Mini Plate Boundary Observatory' experiment for the emplacement of borehole strainmeters. The field component of the study consists of thermal logging and the collection of drill cuttings and rock samples for the determination of thermal physical rock properties. Thermal physical rock properties will be measured using modern laboratory techniques. These boreholes will be re-logged through time to investigate thermal transients (e.g., fluid flow, ground surface temperature changes, thermal events associated with faulting). The modeling component of this project is aimed at resolving: I ) the nature of heat transfer and variation of heat flow along this complex plate boundary; 2) the thermal conditions at both the lower and upper limits of seismicity; and 3) the thermal influence on deformation transients as determined from geodetic data and viscoelastic models of deformation. The field area is ideal for the proposed work because the San Francisco Bay Area has relatively high heat flow (~85 mW m-2) and high strain rates. These two properties maximize opportunities to investigate relationships between the thermal regime of the crust and aseismic transients.