CSEDI Collaborative Research: Grand Challenge for Experimental Study of Plastic Deformation Under Deep Earth Conditions

CSEDI合作研究：深地条件下塑性变形实验研究的巨大挑战

• 批准号: 1361276
• 负责人: Yanbin Wang
• 金额: $ 36.1万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1361276&HistoricalAwards=false
• 关键词: CSEDI; Collaborative; Research; Grand; Challenge

The goal of this research program is to develop and utilize experimental capabilities for studying the plastic properties of rocks at conditions of the deep Earth. Over geologic time we see that continents have been ripped apart with plate boundaries punctuated by earthquakes and volcanoes. However, over the vast regions of the Earth, these processes proceed smoothly and slowly. While earthquakes express the dynamic character of Earth deformation, the slow movement of the continents provides the driving force. The enabling process for this large-scale motion is the plastic deformation of rocks throughout the Earth's mantle. The foundation of plate tectonics rests on the contention that rocks deform slowly but surely at the high pressure and temperature of the deep Earth. This research program is to continue to build experimental capabilities to quantify the plastic character of rocks as a function of depth in the Earth. This program works at the juncture of high-pressure apparatus development and national synchrotron facilities that can provide intense x-ray probes. This union promises experimental capabilities that increase the depth range of the Earth that we can access, with high precision measurement, by a factor of 100 from previous studies. The data that will come from this program will enable testing and modifying of models of Earth evolution. These deformation facilities enable new directions in Earth material research at mantle pressure and temperature including elastic wave attenuation at seismic frequencies, reaction kinetics, thermal diffusivity, and relationship of lattice preferred orientation to deformation geometry, which links seismic anisotropy to flow history. They also provide a potential facility and technical knowhow for studying material strength and plasticity at extreme conditions such as those generated in the next generation power plants.Stress, strain, pressure, and temperature are the primary variables that need to be measured during a deformation experiment. With the aid of the national synchrotrons (the Advanced Photon Source and the National Synchrotron Light Source), the investigators have developed the tools to make these measurements. They have also built the first generation of high-pressure apparatus for introducing 'large - volume high pressure' technology into deformation machines. They are now able to make accurate rheology experiments at pressures 1 to 2 orders of magnitude higher than could be achieved 10 years ago. The next phase is to take full advantage of the current hydrostatic high-pressure equipment, including advanced technologies for making polycrystalline diamonds, to reach lower mantle conditions. The goals of this program are to 1) increase the pressure range for deformation experiments to 30 - 40 GPa, well into the lower mantle, 2) improve measurement resolution of stress and strain with a combination of hardware and software developments, 3) enable simultaneous measurements of a sample properties such as preferred orientation of grains and acoustic velocity, 4) explore advanced techniques such as those developed by the synchrotron community but may be useful to earth science goals. These are often high risk, but high return tools such as white beam Laue diffraction that could yield very detailed information about the individual grains within a polycrystal.

该研究计划的目的是开发和利用实验能力来研究深地球条件下岩石的塑料特性。 在地质时期，我们看到大陆被地震和火山刺破的板界撕裂了。 但是，在地球的广阔地区，这些过程顺利而缓慢地进行。 地震表达了地球变形的动态特征时，大陆的缓慢运动提供了驱动力。 这种大规模运动的能力过程是岩石在整个地幔中的塑性变形。 板块构造的基础基于岩石在深地球的高压和温度下缓慢但肯定会变形的争论。 该研究计划将继续建立实验能力，以量化岩石的塑性特征，这是地球深度的函数。 该计划在高压设备开发和国家同步设施的关键时刻起作用，这些设施可以提供强烈的X射线探针。 该工会承诺实验能力，从而增加我们可以通过高精度测量的地球深度范围的范围，从以前的研究中提高了100倍。 来自该程序的数据将实现地球演化模型的测试和修改。这些变形设施可以在地幔压力和温度下进行地球物质研究的新方向，包括在地震频率，反应动力学，热扩散率以及晶格优选方向与变形几何学的关系的弹性波衰减，这将旋转性各向异性与流动病史联系起来。它们还提供了潜在的设施和技术知识，用于在极端条件下（例如下一代发电厂产生的材料强度和可塑性）进行研究。压力，应变，压力和温度是在变形实验中需要测量的主要变量。借助国家同步加素（高级光子源和国家同步器光源），研究人员开发了进行这些测量的工具。他们还建立了第一代高压设备，用于将“大型高压”技术引入变形机中。现在，他们能够以比十年前实现的压力高1到2个数量级进行准确的流变学实验。下一阶段是充分利用当前的静水压高压设备，包括制造多晶钻石的高级技术，以达到较低的地幔条件。 该计划的目标是1）将变形实验的压力范围增加到30-40 GPA，井到较低的地幔中，2）改善压力和压力的测量分辨率，以及硬件和软件开发的结合，3）启用同时测量样本属性，例如，由Grains的偏好和声音范围的syfique and syfore syfique and syefique and syfique velique and syfore vely consefiques and expliques nove bunderique and sevely bunderique vely bunsore bunsore bunsore bunsore bunsore bunsore bunsore bunsore bun a）对地球科学目标有用。 这些通常是高风险，但是高回报工具（例如白梁laue衍射）可能会产生有关多晶中各个晶粒的非常详细的信息。