Geochronology of Cretaceous-Tertiary Magmatism Across Chihuahua and Sonora, Mexico, and its Significance for Plate Tectonics

墨西哥奇瓦瓦州和索诺拉州白垩纪-第三纪岩浆作用的年代学及其对板块构造的意义

• 批准号: 8720380
• 负责人: Fred McDowell
• 金额: $ 9.98万
• 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: 1988
• 资助国家: 美国
• 起止时间: 1988-02-01 至 1991-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8720380&HistoricalAwards=false
• 关键词: Geochronology; Cretaceous; Tertiary; Magmatism; Across

Relative motions between plates in the east Pacific region during the past 150 m.y. have produced a variety of structural and magmatic features along the western North American plate margin. Compilation of age and composition for the magmatic activity along this margin have been used to reconstruct the shifting patterns of magmatic belts and to relate them to changing geometry of subduction and depth of related magma generation. However, due to the distribution and quality of these data more than one interpretation is possible. This research will test between the present hypotheses by using age data acquired along a single corridor across the Cretaceous and Tertiary magmatic belts in western Mexico. Results are expected to determine whether previously proposed regular migrations in western Mexico are adequately supported by chronology, how far inland these patterns can be followed, whether there are discontinuities due to lateral translations and whether resulting patterns can be related to subduction events.

在过去150多年里，东太平洋地区板块间的相对运动在北美西部板块边缘形成了各种各样的构造和岩浆特征。利用该边缘岩浆活动的年龄和成分汇编，重建了岩浆带的移动模式，并将其与俯冲几何形状和相关岩浆生成深度的变化联系起来。然而，由于这些数据的分布和质量，可能有不止一种解释。这项研究将通过使用沿墨西哥西部白垩纪和第三纪岩浆带的单一走廊获得的年龄数据来测试目前的假设。预计结果将确定之前提出的墨西哥西部的规律迁移是否得到年代学的充分支持，这些模式可以在多远的内陆被遵循，是否存在横向平移引起的不连续性，以及由此产生的模式是否与俯冲事件有关。