A Study of Metamorphic Fluids and Processes through Integrated use of Petrology and Fluid Inclusions

综合利用岩石学和流体包裹体研究变质流体和过程

• 批准号: 8917185
• 负责人: Sakiko Olsen
• 金额: $ 7.92万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-01-15 至 1992-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8917185&HistoricalAwards=false
• 关键词: Study; Metamorphic; Fluids; Processes; through

There is no doubt that fluids are present in some form during metamorphism of most rocks. It is difficult, however, to obtain the information on metamorphic fluids from a rock because little of the fluids is left in the rock except as volatile components in some minerals. Neither is it possible to sample the fluid during metamorphism except in very limited cases of low-grade metamorphism (=geothermal field). Theoretical calculations using mineral compositions in the rock can give a fluid composition with which the minerals now present in the rock must have been in equilibrium with. However, the amounts of some components in the fluid such as Cl and N cannot easily be obtained by calculations. In addition, there probably were several generations of fluid that have passed through the rock for which the compositions cannot be calculated: only the fluid in equilibrium with the present mineral assemblages can be calculated. The results from such petrological calculations will be compared to the fluid present in small cavities in the minerals in the rock (=fluid inclusions). These fluid inclusions are thought to have trapped fluids that were present in the rock at different times during its metamorphic history. Two small areas, in Texas and south-central Maine, will be studied. The results should tell us whether the fluid inclusions can be used as the samples of unmodified metamorphic fluids in these and other areas. The results should also increase understanding of the nature of the fluid phase and its role during metamorphism and contribute toward a better understanding of metamorphic processes in general.

毫无疑问，流体以某种形式存在， 在大多数岩石的变质过程中。 然而，很难 从岩石中获得变质流体的信息， 除了挥发性的液体， 一些矿物中的成分。 也不可能取样 变质作用期间的流体，除了在非常有限的情况下 低级变质作用 理论 利用岩石中的矿物成分进行计算， 岩石中的矿物所含的流体成分 必须与之平衡。 然而，一些数量 流体中的成分如Cl和N不能容易地被 通过计算获得。 此外，可能还有 经过岩石的几代流体 无法计算其组成：只有流体 与目前的矿物组合相平衡， 计算了 这种岩石学计算的结果将 与存在于小腔中的流体相比， 岩石中的矿物。 这些流体包裹体 被认为是岩石中存在的液体 在其变质历史的不同时期。 两个小 德克萨斯州和缅因州中南部的一些地区将被研究。 的 结果应该告诉我们流体包裹体是否可以用于 作为未改性变质流体的样品， 其他领域。 研究结果还应增加对以下问题的了解： 流体相的性质及其在变质作用中的作用 并有助于更好地了解变质 过程一般。