An Examination of the Nature and Timing of Pluton Emplace- ment, Northern Sierra Nevada, Calfornia

对加利福尼亚州内华达山脉北部的岩体侵位的性质和时间的检验

• 批准号: 8904706
• 负责人: Othmar Tobisch
• 金额: $ 4.68万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-01 至 1992-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8904706&HistoricalAwards=false
• 关键词: Examination; Nature; Timing; Pluton; Emplace

Relationships between dated plutons and tectonic deforma- tion have been widely used to constrain timing of regional deformation. The validity of this procedure relies on the ability to determine emplacement-related structures in the plutons from super-imposed tectonic structures. Existing guide- lines are not diagnostic and therefore criteria for distinguish- ing pre-, syn-, and post- tectonic plutons are controversial. This project will carry out a detailed examination of the Merrimac pluton in the Northern Sierra Nevada, California to estimate the strain fields in and around the granitoid. Additionally, computer modeling that simulates pre-, syn-, and post- tectonic pluton emplacement under coaxial and non-coaxial deformation will be performed. By comparing planar sections through the computer generated strain fields with the strain fields obtained from the field data, it is expected that more rigorous criteria will result for recognizing pre-, syn-, and post- tectonic plutons, and therefore, provide more reliable constraints for determining the age of structures in orogenic belts.

定年岩体与构造变形之间的关系已被广泛用于约束区域变形的时间。 该程序的有效性依赖于从叠加的构造结构中确定岩体中与就位相关的结构的能力。 现有的指南不能用于诊断，因此区分构造前、同构造和构造后岩体的标准存在争议。 该项目将对加利福尼亚州内华达山脉北部的梅里马克岩体进行详细检查，以估计花岗岩内部和周围的应变场。 此外，还将进行计算机建模，模拟同轴和非同轴变形下的构造前、同构造和构造后岩体侵位。 通过将计算机生成的应变场的平面剖面与从现场数据获得的应变场进行比较，预计将产生更严格的标准来识别构造前、同构造和构造后岩体，从而提供更可靠的约束用于确定造山带结构的年龄。