U.S.-Australia Cooperative Research: Southeastern Australian Test of the Role of Eustasy in Development of Small-Scale Upper Devonian Cycles

该奖项将支持博士之间的合作研究。 巴克内尔大学的爱德华·科特和帕特里克·康纳汉博士 Macquarie University，澳大利亚拟议研究 将试图确定是否小规模（第五或 六阶）海平面波动在世界范围内经历 在晚泥盆纪时期，从而有助于辩论 关于北美和欧洲的这种周期是否 是由全球性的海平面变化引起的， 流程. 基本方法是调查海洋和 上泥盆统边缘海相沉积序列 Lachlan褶皱带的继承（Lambie群） 澳大利亚东南部，以确定他们是否包含 有节奏的图案，一到十米厚， 深度的交替变化。如果这种节奏的交替 的水深，计算的周期， 这种变化将允许与周期性进行比较， 为同时代（弗兰斯尼亚-法门期）层序确定 在北美的阿巴拉契亚盆地如果 澳大利亚东南部的周期性中心约为10万年 像北美一样，这不仅会使 支持海平面升降控制周期发展，但它 强化了尤先科与米兰科维奇有关的观点 类型的轨道变化。然而，如果小规模的循环， 相对水深的变化不属于Lambie群 以及它在澳大利亚东南部的近亲， 更难为欧盟辩护， 北美的周期。 该项目代表了 新西兰集团作出了重大贡献， 对沉积模式的了解， 构造板块的相互作用和科特的工作是否 晚泥盆世时期小规模的海洋波动 海平面变化 这是一项重要的工作， 关于这种周期是否在北美和 欧洲是由海平面上升或局部构造运动引起的 流程.

This award will support collaborative research between Dr. Edward Cotter of Bucknell University and Dr. Patrick Conaghan of Macquarie University, Australia. The proposed research will attempt to determine whether small-scale (fifth- or sixth-order) sea-level fluctations were experienced worldwide during Late Devonian time, thereby contributing to the debate concerning whether such cycles in North America and Europe were caused by eustatic (world-wide) or more local tectonic processes. The basic approach is to investigate marine and marginal-marine sedimentary sequences in the Upper Devonian succession (Lambie Group) of the Lachlan Fold Belt in southeastern Australia to determine whether they contain rhythmic patterns, one to ten meters thick, showing cyclically alternating changes of depth. If such rhythmic alternations of water depth are found, calculation of the periodicities of such changes will permit comparison with the periodicities determined for contemporaneous (Fransnian-Famennian) sequences in the Appalachian Basin of North America. Should the southeastern Australian periodicities center around 100,000 years, as is the case in North America, not only will this support a eustatic control of cycle development, but it reinforces the idea that eustasy was related to Milankovitch- type orbital variations. However, if small-scale cycles of change in relative water depth are not in the Lambie Group and its correlatives in southeastern Australia, it will be much more difficult to argue for eustasy as the control on the cycles in North America. This project represents excellent collaboration between the New Zealand group which has made major contributions to knowledge of the patterns of sedimentation that result from interaction of tectonic plates and the Cotter work on whether small-scale sea fluctuations during Late Devonian time were eustatic. This is important work which will contribute to the debate concerning whether such cycles in North America and Europe were caused by eustatic or more local tectonic processes.