Mesoproterozoic Tectonic Evolution of the Southern Margin of Laurentia

劳伦南南缘中元古代构造演化

• 批准号: 9706692
• 负责人: Sharon Mosher
• 金额: $ 15.38万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-07-15 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9706692&HistoricalAwards=false
• 关键词: Mesoproterozoic; Tectonic; Evolution; Southern; Margin

9706692 Mosher A leading problem in understanding the late Proterozoic of North America relates to the Grenville orogeny and its relationship to the crustal blocks involved in it. South of the great lakes exposure of the relevant rocks is almost non-existent, and thus the exposures of the Llano uplift, and those in west Texas become unusually critical in deciphering these relationships. In fact, the exposures that do exist there seem to reveal a rather more complicated history of not only typical lower crustal Grenville rocks, but also eclogites, possible fragments of the mid continental Grainte-Rhyolite terrane, and a so-far unrecognized volcanic terrane. This geochronological, petrological, and structural study of these rocks will provide fundamental limiting and defining data that will strongly constrain our understanding of the tectonic evolution of the southern Grenville region.

[706692] Mosher了解北美晚元古代的一个主要问题是格伦维尔造山运动及其与参与造山运动的地壳块体的关系。五大湖以南的相关岩石的暴露几乎不存在，因此，在破译这些关系时，拉诺隆起的暴露和德克萨斯州西部的暴露变得异常重要。事实上，那里确实存在的暴露物似乎揭示了一段相当复杂的历史，不仅有典型的下地壳格伦维尔岩石，还有榴辉岩，可能是中大陆粒纹岩-流纹岩地体的碎片，以及迄今为止尚未被识别的火山地体。这些岩石的地质年代学、岩石学和构造研究将提供基本的限制和定义数据，这些数据将有力地限制我们对格伦维尔南部地区构造演化的理解。