COLLABORATIVE RESEARCH: A Sequence-, Chemo-, and Biostratigraphic Study of Late Early Cambrian Rocks, Southern Selwyn Basin, Mackenzie Mountains, Canada

摘要：合作研究：加拿大麦肯齐山脉塞尔温盆地南部早寒武世晚期岩石的层序、化学和生物地层学研究该项目研究了大约5. 2亿年前在所谓的寒武纪辐射期间发生的动物进化的早期事件是如何受到环境变化的影响的。 为了研究这些问题，我们将研究加拿大西北地区麦肯齐山脉早寒武世岩石的沉积学、古生物学和地球化学。 这是一个偏远的地方，但它有一个非常完整的地质记录早寒武世的间隔。 这为我们提供了一个了解浅水和深水环境中的生命形式和环境的窗口，这种情况在这个时期没有其他地方发现。我们将研究的环境变化类型包括海平面的相对变化和温度变化：这两者部分相关。 在寒武纪辐射期间，相对温暖和寒冷的气候之间可能有快速的振荡。 为了确定这些环境变化的性质，有必要了解岩石类型的变化，我们将详细研究。 研究这些变异发生的时间也是必要的;我们将通过记录化石物种的序列和使用化学同位素来完成这一点。 该地区和其他地方的进化变化和灭绝事件，以及它们与环境变化的关系，也将被记录下来。 通过这种方式，我们不仅可以更好地理解地球历史上这一关键时期发生的环境变化的性质，而且还可以确定生命历史上的一个关键事件是如何从根本上受到气候变化的驱动的。

ABSTRACT Collaborative Research: A Sequence-, Chemo-, Biostratigraphic Study of Late Early Cambrian Rocks, Southern Selwyn Basin, Mackenzie Mountains, Canada This project investigates how early episodes of animal evolution, which occurred roughly 520 million years ago during the so-called Cambrian radiation, were influenced by environmental changes. To investigate these issues we will study the sedimentology, paleontology, and geochemistry of the Early Cambrian rocks of the Mackenzie Mountains, Northwest Territories, Canada. This is a remote location, but it has a remarkably complete geological record for the Early Cambrian interval. This gives us a window into the life forms and environments of both shallow and deep water settings, a situation found nowhere else for this time period. The types of environmental changes we will study include both changes in the relative level of the seas as well as temperature changes: the two are partly linked. During the Cambrian radiation there may have been rapid oscillations between relatively warm and cold climates. To determine the nature of these environmental changes, it is necessary to understand the variations in the rock types, which we will study in detail. It is also necessary to study when these variations occurred; this we will accomplish by documenting the sequence of fossil species and through use of chemical isotopes. Evolutionary changes and extinction events in this region, and elsewhere, and their relationship to the environmental changes, will also be documented. In this manner, we will not only come to better understand the nature of the environmental changes that occurred during this critical interval in earth history, but we will also determine how one of the key episodes in the history of life may have been fundamentally driven by climatic changes.