Kinetic Studies of Geological Processes

地质过程的动力学研究

• 批准号: 8709346
• 负责人: Bruno Giletti
• 金额: $ 15.7万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-12-01 至 1991-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8709346&HistoricalAwards=false
• 关键词: Kinetic; Studies; Geological; Processes

This project represents a continuation of research previously supported by NSF grant EAR82-18984, involving experimental studies of the diffusion of oxygen and cations in minerals. Specific objectives are to: 1.Measure oxygen diffusion in biotite, muscovite, and phlogopite micas, and in magnetite, garnet, and clinopyroxene, all under hydrothermal conditions, 2. Complete the measurements of Rb, Sr, and Pb diffusion in orthoclase, and of the REE, Nd and Er, in hornblende, and 3. To use the new methods developed in (2) to measure the diffusion kinetics of these elements in clinopyroxene, garnet, apatite, and plagioclase. The results will permit the quantitative assessment of the behavior of the geochronologically important systems Rb-Sr, Sm-Nd, and U-Th-Pb in rocks during episodes of heating. It will also be possible to set constraints on models of basalt genesis by partial melting in the mantle. It is important to know if the basalt magmas were not in chemical and isotopic equilibrium with their source rocks for all their constituents.

该项目是先前由美国国家科学基金会资助的EAR82-18984研究的继续，涉及氧和阳离子在矿物中扩散的实验研究。具体目标是：1.在水热条件下测量氧在黑云母、白云母和金云母云母中的扩散，以及在磁铁矿、石榴石和单斜辉石中的扩散；2.完成斜长石中Rb、Sr和Pb的扩散以及角闪石中REE、ND和Er的测量。3.用(2)中发展的新方法测量这些元素在单斜辉石、石榴石、磷灰石和斜长石中的扩散动力学。这一结果将有助于定量评估岩石中重要的年代学系统Rb-Sr、Sm-ND和U-Th-Pb在加热过程中的行为。通过地幔部分熔融对玄武岩成因模型进行限制也是可能的。重要的是要知道玄武岩岩浆是否与其源岩的所有成分都没有处于化学和同位素平衡状态。