COLLABORATIVE RESEARCH: Using plate circuits to constrain motion between East and West Antarctica

合作研究：利用板电路限制南极洲东西部之间的运动

• 批准号: 0944711
• 负责人: Joann Stock
• 金额: $ 19.08万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0944711&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Using; plate; circuits

This proposal will address the motion between East and West Antarctica. The estimates of motion in the Late Cretaceous and Cenozoic come from summing the plate circuit linking East Antarctica to Australia to the Lord Howe Rise to the Pacific plate to West Antarctica. However, major uncertainties remain in the history of the plate motions in this region, leading to widely different implications for the global plate circuit, without a clear indication of which model is correct. The PIs propose to analyze this motion in two parts: motion since 42 Ma and motion before 42 Ma. For the younger time interval, the PIs will improve accuracy of rotations by taking advantage of an unusual plate geometry that enables them to solve a five-boundary, four-plate configuration. For the older time interval, the only way to calculate motion between East and West Antarctica is via the long Aus-Pac plate circuit. The difficulty in this time interval is that there are three sets of rotations with distinctly different results for the Aus-East Ant boundary. The disagreement over the fundamental motion between Aus and Ant before 50 Ma leads to large differences in the predicted motion in the Western Ross Sea and near Ellsworth Land. The PIs propose to re-examine the key elements in the Aus-Pac plate circuit with the objective of reducing uncertainties, using quantitative methods where possible, and resolving some of the critical issues involving alternative interpretations. Broader impacts: The scientific impacts of this work are an improved understanding of Antarctic plate tectonic history to incorporate into global models. This project will support one graduate student at each institution. The results of the project will be made available in the global plate motion and plate reconstruction databases. In addition, results will be used for outreach work to middle school groups. Cande has made an animated movie of the plate motions around the Aus-Pac plate circuit that he uses as part of his undergraduate and graduate teaching. He plans to update and expand this animation using the results of this project.

该提议将解决东南极洲东部和西部之间的动议。白垩纪晚期和新生代晚期运动的估计是从将东南极洲东部与澳大利亚东部与豪勋爵相连到太平洋板到太平洋板到南极洲西部的板电路。然而，该区域的板运动历史上仍然存在主要的不确定性，从而导致对全球板电路的含义发生了很大不同，没有明确指示哪种模型是正确的。 PI提议将这一运动分为两部分：自42 Ma以来运动和42 Ma之前的运动。对于年轻的时间间隔，PI将通过利用不寻常的板几何形状来提高旋转的准确性，从而使它们能够求解五势的四板配置。对于较旧的时间间隔，计算东南极洲之间运动的唯一方法是通过长AUS-PAC板电路。 在此时间间隔中的困难是，对于Aus-East Ant边界有三组旋转，结果明显不同。在50 MA之前，AUS和ANT之间的基本运动的分歧导致西部罗斯海和埃尔斯沃思土地附近的预测运动有很大差异。 PI提议在AUS-PAC板电路中重新检查关键要素，目的是在可能的情况下使用定量方法来减少不确定性，并解决涉及替代解释的一些关键问题。更广泛的影响：这项工作的科学影响是对南极板块构造历史的一种改进的了解，以纳入全球模型。该项目将支持每个机构的一名研究生。该项目的结果将在全球板运动和板重建数据库中提供。此外，结果将用于中学团体的外展工作。 Cande在Aus-Pac Plate Circuit上制作了一部动画电影，作为他在本科和研究生教学的一部分中使用的动画动作。他计划使用该项目的结果更新和扩展该动画。