The Assembly of East Gondwana: A Proterozoic Perspective from India

东冈瓦纳大陆的组装：来自印度的元古代视角

• 批准号: 0409101
• 负责人: Joseph Meert
• 金额: $ 17.45万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0409101&HistoricalAwards=false
• 关键词: Assembly; East; Gondwana; Proterozoic; Perspective

This proposal will allow the principal investigator and his colleagues to determine the paleogeographic position of India in relationship to other continental masses during the time period from 700 to 2100 million years ago. The research will be based on a combination of geochronological and paleomagnetic studies on rocks from central and southern India and will involve a collaborative effort between Indian and U.S. scientists. This particular interval of geologic time is significant because it encompasses at least two episodes of severe (global?) glaciations; a period of time where the continents may have moved, in unison, at velocities much faster than those witnessed at other times in Earth history (via true polar wander); the formation and destruction of two supercontinents (Columbia and Rodinia) and it also preceded the explosion of life in the Cambrian. The results will allow the researchers to examine possible relationships between paleogeography, climate and biological evolution during one of the most unusual periods in Earth history. For example, it has been proposed that the breakup of the supercontinent Rodinia was preceded by a rapid interval of continental motion and also that this breakup provided a trigger for one of the 'Snowball' glaciations. These 'Snowball' glaciations in turn created an ecologic bottleneck for the extant organisms and may have triggered a unique biological adaptation leading to the Cambrian explosion.

该提议将使首席研究员和他的同事能够确定 700 至 21 亿年前印度相对于其他大陆块的古地理位置。 这项研究将基于对印度中部和南部岩石的地质年代学和古地磁研究的结合，并将涉及印度和美国科学家之间的合作努力。这个特殊的地质时间间隔非常重要，因为它至少包含两次严重的（全球？）冰川作用。在一段时间内，大陆可能以比地球历史上其他时期所目睹的速度快得多的速度一致移动（通过真正的极地漂移）；两个超级大陆（哥伦比亚和罗迪尼亚）的形成和毁灭，也先于寒武纪生命的爆发。 这些结果将使研究人员能够研究地球历史上最不寻常的时期之一的古地理、气候和生物进化之间可能的关系。 例如，有人提出，罗迪尼亚超大陆分裂之前有一段快速的大陆运动，而且这种分裂引发了“雪球”冰川之一。 这些“雪球”冰川反过来给现存生物体造成了生态瓶颈，并可能引发了独特的生物适应，导致寒武纪爆发。