Processes of Isotopic Resetting in the Contact Aureole of the Laramie Anorthosite Complex

本研究项目的主要目标是 了解U-Pb和Sm的同位素重置过程， 拉勒米接触晕矿物中的钕系 斜长岩杂岩 的时间-温度曲线， 光环将使用常规的相平衡来精制， 氧同位素测温与Ar-Ar黑云母和角闪石 冷却年龄 生成的配置文件将用于 对闭合温度和复位施加限制 矿物中U-Pb和Sm-Nd系统的过程 如钛铁矿、硅铝石、磷灰石、石榴石和独居石。 U-Pb和Sm-Nd的形成温度比较 来自反应性和非反应性岩石的矿物年龄重置 光环中的类型将允许检查效果 再平衡时的矿物反应和体积扩散 各种同位素系统的。

The principal objective of this research project is to understand isotopic resetting processes for the U-Pb and Sm- Nd systems in minerals in the contact aureole of the Laramie Anorthosite Complex. The time-temperature profile of the aureole will be refined using conventional phase equilibria, oxygen isotope thermometry and Ar-Ar biotite and hornblende cooling ages. The resulting profile will then be used to place constraints on the closure temperatures and resetting processes for the U-Pb and Sm-Nd systematics in minerals such as ilmenite, sphene, apatite, garnet and monazite. Comparison of the temperatures at which the U-Pb and Sm-Nd ages reset in minerals from reactive and non-reactive rock types in the aureole will permit examination of the effects of mineral reactions and volume diffusion on reequilibration of the various isotopic sytems.