Investigation of Comagmatic Complexes Using Isotope Systematics

这项提议是要求继续提供资金，以开展正在进行的关于同源岩浆火成岩协会成因的研究计划。这项研究的主要目的是阐明火成岩套的岩石成因，并研究地幔岩浆在大陆地壳环境中的变化。一个辅助目标是确定岩浆源区的性质和岩浆产生事件的时间性质，以促进我们在地球动力学背景下对板内岩浆作用的理解。研究地点是新英格兰、魁北克南部和津巴布韦的碱性复合体。它们通常是由不同成分的连续侵入体组成的小型浅海体。该方法利用岩相学、主量元素和痕量元素，以及具有密切时间控制的稳定和放射性同位素关系来建立特定的成岩模式。最近的研究工作提供了关于这些岩浆杂岩的一般开放系统演化的性质和细节以及岩浆活动的来源和时间的性质的宝贵信息。持续的研究不仅对研究中的具体地方和省份，而且对其他地方的类似情况，都应该是非常有价值的。

This proposal is a request for continued funding to carry out an ongoing research program on the genesis of comagmatic igneous rock associations. The primary aim of this research is to clarify the petrogenesis of igneous suites and to examine modifications of mantle-derived magmas with the continental crust environment. An auxiliary goal is to determine the character of the magma source regions and the temporal nature of the magma production events in order to advance our understanding of intraplate magmatism in a geodynamic context. The localities of study are alkaline complexes in New England, southern Quebec, and Zimbabwe. These are generally small, epizonal bodies composed of successive intrusions of varying composition. The methodology uses petrographic, major and trace element, and stable and radiogenic isotopic relationships with close temporal control to formulate specific petrogenetic models. Recent research efforts have yielded valuable information on the nature and details of the general open- system evolution of these magmatic complexes and on the nature of the sources and the timing of magmatism. Continued research should be highly rewarding not only for the specific localities and provinces under study but also for analogs elsewhere.