Contact Aureole Rheology

联系 Aureole 流变学

• 批准号: 0106557
• 负责人: Aaron Yoshinobu
• 金额: $ 11.49万
• 依托单位: Texas Tech University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-15 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0106557&HistoricalAwards=false
• 关键词: Contact; Aureole; Rheology

0106557 YoshinobuRates of processes control a wide variety of geologic phenomena. With the development of more precise and refined radiometric age dating techniques, it is becoming increasingly apparent that processes in magmatic arcs such as magma generation and ascent may occur at relatively fast rates and over a wide range of durations. In contrast, existing data sets for regional deformation suggest that rates of various processes such as faulting, shearing, and folding are several orders of magnitude slower than rates of magma generation, migration, and emplacement. This research is utilizing field, microstructural, and experimental rock deformation data sets to address the following questions: (1) What micro- and macro-scale deformation mechanisms accommodate deformation in contact aureoles? (2) What are the magnitudes of stress in the host rocks during plastic deformation associated with chamber construction? (3) What are the host rock strain rates during plastic deformation associated with chamber construction? And (4) What are "typical" viscosities in contact aureoles? Detailed mapping and microstructural analysis conducted on two pluton-host rock systems, exposed in the Clark Mountains of eastern California, as well as application of experimentally-derived flow laws and paleo-piezometers (paleo-stress gauges) to deformed contact aureole rocks are currently being carried out to evaluate these questions and provide constraints on contact aureole stresses, strain rates and viscosities.

0106557 Yoshinobu 过程的速率控制着各种各样的地质现象。 随着更精确和完善的放射性测年技术的发展，越来越明显的是，岩浆弧中的过程（例如岩浆生成和上升）可能以相对较快的速度和较宽的持续时间发生。 相比之下，现有的区域变形数据集表明，断层、剪切和褶皱等各种过程的速率比岩浆生成、迁移和侵位的速率慢几个数量级。这项研究利用现场、微观结构和实验岩石变形数据集来解决以下问题：（1）什么微观和宏观变形机制适应接触光环的变形？ (2) 与硐室建造相关的塑性变形期间，主岩中的应力大小是多少？ (3) 与硐室建造相关的塑性变形过程中主岩应变率是多少？ (4) 接触光环的“典型”粘度是多少？目前正在对暴露于加利福尼亚州东部克拉克山脉的两个深成体围岩系统进行详细的测绘和微观结构分析，以及将实验得出的流动定律和古压力计（古应力计）应用于变形接触光环岩石。正在进行评估这些问题并提供对接触光环应力、应变率和粘度的约束。