Pliocene to Recent Basic Magmatism in the East-Central Mexican Volcanic Belt

该项目将利用实地研究来确定MVB中东部地区上新世至近期基性火山岩的时空分布。除了矿物的电子探针分析外，还将对选定的样品进行常量元素、微量元素、锶、钕、铅和氧同位素比率的分析。一些较老的岩石将被确定为K-Ar方法的年代。这些数据将与MVB中有关基性火山岩的现有数据相结合，通过对有助于这些基性岩浆来源的材料的成分施加限制，来开发和/或测试MVB中基性岩浆的起源模型。该项目将确定各类基性火山岩的分布与地壳结构、俯冲岩石圈的年龄和深度以及岩石年龄之间存在的任何相关性。它还将记录最近才被确认产于与俯冲有关的火山弧中的各种类型的基性火山岩，并将为了解更常见、更多分馏和/或更受污染的钙碱性岩石提供一个基础。

This project will use field studies to determine the spatial and temporal distribution of Pliocene to Recent basic volcanic rocks in the east-central MVB. Selected samples will be analyzed for major elements, trace elements, Sr, Nd, Pb, and O isotopic ratios, in addition to electron microprobe analyses of minerals. Some of the older rocks will be dated K-Ar methods. This data will be combined with existing data on basic volcanic rocks in the MVB to develop and/or test models for the origin of basic magmas in the MVB by placing constraints on the composition of materials contributing to the source of these basic magmas. The project will determine any correlation that exist between the distribution of the various types of basic volcanic rocks with crustal structure, age of and depth to the subducted lithosphere, and age of the rocks. It will also document the occurrence of various types of basic volcanic rocks that have only recently been recognized to occur in subduction-related volcanic arcs, and will provide a basis upon which the more common, more fractionated, and/or more contaminated calc-alkaline rocks can be understood.