The Assembly of East Gondwana: A Proterozoic Perspective from India

这一提议将使首席研究员和他的同事能够确定印度在7亿至21亿年前与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学研究，并将涉及印度和美国科学家之间的合作。这段特殊的地质时期意义重大，因为它包含了至少两次严重的（全球性的？）冰川作用;在这段时间里，大陆可能以比地球历史上其他时期（通过真正的极地漂移）快得多的速度一致地移动;两个超级大陆（哥伦比亚和罗迪尼亚）的形成和毁灭，它也先于寒武纪的生命爆发。 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的可能关系。 例如，有人提出，超大陆Rodinia的分裂之前是一个快速的大陆运动间隔，而且这种分裂提供了一个“雪球”冰川的触发器。 这些“雪球”冰川反过来又为现存的生物体创造了一个生态瓶颈，并可能引发了一种独特的生物适应，导致寒武纪大爆发。

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.