Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till

0538195 Marone该奖项支持一个项目进行实验室实验和数值模拟，以确定动态应力下冰碛物的本构特性，并测试冰碛物的颗粒特性是否足以与大型冰流弹性耦合的假设，以重现触发滑动和冰下地震活动的现场观察。 测试将在受控温度和应力条件下在伺服控制双轴剪切装置中进行，这将允许详细研究滑动和微观结构过程。工作的主要重点将是实验室测量。此外，我们将构建连续模型来评估我们的结果是否可以预测复杂的冰盖运动和观测到的冰下地震活动的特征。就更广泛的影响而言，拟议的工作将鼓励岩石力学和冰川学社区之间的互动，并将汇集不同科学背景和词汇但类似问题和数据的成员。该项目将在宾夕法尼亚州立大学培训本科生和研究生，参与的科学家计划在小学班级、童子军团体和社区开放日上做演讲。 结果将在专业会议上提出，并将及时公布。 这项工作将导致更好地了解冰川运动和地震滑动的物理学，这对于了解冰盖动力学和地震灾害至关重要。

0538195MaroneThis award supports a project to conduct laboratory experiments and numerical modeling to determine the constitutive properties of subglacial till under dynamic stressing and to test the hypothesis that granular properties of till are sufficient, when coupled elastically to a large ice stream, to reproduce the field observations of triggered slip and subglacial seismicity. Testing will be carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, which will allow both sliding and microstructural processes to be studied in detail. The main focus of the work will be on laboratory measurements. In addition, we will construct continuum models to evaluate whether our results can predict complex ice sheet motions and observed characteristics of subglacial seismicity. In terms of broader impacts, the proposed work will encourage interactions between the rock-mechanics and glaciology communities and will bring together members of different scientific backgrounds and vocabularies, but similar problems and data. The project will train undergraduate and graduate students at Penn State University and the scientists involved plan to give presentations to grade school classes, scout groups, and at community open houses. Results will be presented at professional meetings and will be published in a timely manner. The work will result in a better understanding of glacial motion and the physics of earthquake slip, which is essential for understanding ice sheet dynamics and earthquake hazard.