Paleomagnetic Investigation of Brunhes-Matuyama Reversal, Chilean Andes

智利安第斯山脉 Brunhes-Matuyama 反转的古地磁调查

• 批准号: 9316544
• 负责人: Laurie Brown
• 金额: $ 6.81万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-12-15 至 1996-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9316544&HistoricalAwards=false
• 关键词: Paleomagnetic; Investigation; Brunhes; Matuyama; Reversal

9316544 Brown The objective of this project is to investigate the behavior of the Earth's magnetic field during a transition from reversed to normal polarity. Recently a sequence of lavas yielding transitional paleomagnetic directions was discovered as part of a larger interdisciplinary study of Volcan Tatara-San Pedro in the central Chilean Andes. Subsequent radiometric dating, using both traditional K-Ar and laser 40/39 Ar techniques, has identified the rocks as being 780,000 years old, the age of the Brunhes-Matuyama (B-M) reversal. Virtual geomagnetic poles (VGPs) from these eleven flows cluster around Australia - Southeast Asia. This detailed study of a Southern Hemisphere reversal record (only the third B-M identified in volcanic rocks) will provide important data for preferred paths and clustered VGP analyses.

这个项目的目的是研究地球磁场从反极性到正极性转变过程中的行为。最近，在对智利安第斯山脉中部的塔塔拉-圣佩德罗火山进行的一项大型跨学科研究中，发现了一系列产生过渡性古地磁方向的熔岩。随后，使用传统的K-Ar和激光40/39 Ar技术的放射性测年法确定了这些岩石的年龄为78万年，即布鲁内斯-松山（B-M）逆转的年龄。这11个流的虚拟地磁极（VGPs）聚集在澳大利亚-东南亚周围。这项对南半球反转记录的详细研究（仅在火山岩中发现的第三个B-M）将为优选路径和聚类VGP分析提供重要数据。