Geochronology and Petrogenesis in Chortis and Xolapa: Implications for Central American Tectonics

从南美洲到北美洲的盘根海拼合，没有给现在的墨西哥南部和中美洲留下地壳空间，因此这些地区是在盘根海解体后形成的，或者是从其他地方来的。目前的信息表明，这些地体具有不协调的地质史，这表明它们的早期历史是无关的。乔尔蒂斯地块是加勒比海板块上唯一具有已知的古生代和可能的元古界历史的地体，被认为是解开加勒比海构造之谜的重要钥匙。该项目将对乔尔蒂斯地块进行地质年代学分析，以将构造事件置于一个坚实的时间框架内。这些数据，结合现有的地质、构造和构造制约因素，将能够检验北美脉状地壳与特定来源之间的关系假说，以及查尔蒂斯地块第三纪构造运移与加勒比海板块发展有关的假说。

The Pangean fit of South to North America leaves no space for the crust of present southern Mexico and Central America, thus these areas formed after the breakup of Pangean or arrived from elsewhere. Present information indicates that these terranes have discordant geologic histories suggesting that their early histories are unrelated. The Chortis block is the only terrane on the Caribbean plate with a known Paleozoic and possible Proterozoic history, and is considered an important key to solving the puzzle of Caribbean tectonics. This project will conduct geochronologic analysis of the Chortis block to place structural events in a firm temporal framework. These data, combined with available geologic, structural and tectonics constraints, will allow testing of hypotheses relating Chortis crust to specific sources in North America, and to test hypotheses relating Tertiary tectonic transport of the Chortis block to the development of the Caribbean plate.