Magnetic Petrology of the Lower Crust: Record from Mafic Xenoliths

磁性岩石学的目标是将磁性研究与岩石学研究相结合，以了解岩石中磁化作用的发展和变质。首席调查员将启动对下大陆地壳磁性岩石学的长期研究。作为该计划的初始阶段，这项建议侧重于来自会聚弧缘和大陆裂谷带的地壳捕虏体。来自(1)阿留申弧、(2)日本、(3)里奥格兰德裂谷和(4)南极洲火山中心的镁铁质包体将除了标准的岩石磁化技术外，还将用岩石学-显微探针法进行分析。预计这一结果将对MAGSAT和区域航磁调查所揭示的长波长磁异常的候选源材料提供限制。它们还应提供有关下地壳岩石磁化行为的岩石学控制的基本信息。

Magnetic petrology has as its goal the integration of magnetic property studies with petrologic studies for the purpose of understand the development and modification of magnetization in rocks. The principal investigator will initiate a long-term study of the magnetic petrology of the lower continental crust. As the initial phase of this program, this proposal focuses on crustal xenoliths from convergent arc margins and continental rift zones. Mafic xenoliths from volcanic centers in the (1) Aleutian arc, (2) Japan, (3) Rio Grande Rift and (4) Antarctica will be analyzed by petrographic-microprobe methods in addition to standard rock magnetization techniques. The results are expected to provide constraints on candidate source materials for the long-wavelength magnetic anomalies revealed by Magsat and regional aeromagnetic surveys. They should also provide basic information on petrologic controls responsible for the magnetization behavior of lower crustal rocks.