Collaborative Research: Investigating the interplay between creeping and seismogenic fault sections using large-scale laboratory experiments and high-resolution numerical models

合作研究：利用大规模实验室实验和高分辨率数值模型研究蠕动断层和发震断层之间的相互作用

基本信息

批准号：
1763499
负责人：
Gregory McLaskey
金额：
$ 38.9万
依托单位：
Cornell University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-04-15 至 2022-03-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1763499&HistoricalAwards=false
关键词：
Collaborative Research Investigating interplay between

项目摘要

Frictional and material properties vary along tectonic faults and directly affect the nucleation, propagation and arrest of earthquakes. This heterogeneous character of natural faults is what makes earthquakes complex and difficult to predict. Some fault sections are mostly locked but recurrently host earthquakes. Other sections are creeping and generally stable. However, under poorly understood circumstances, earthquakes that nucleated in an unstable section can propagate far into stable fault sections and result in particularly large and destructive events. This project investigates the causes that lead to activation of the creeping fault sections by combining large-scale laboratory earthquake experiments with physics-based numerical simulations. The modeled fault consists of stable and unstable parts which realistically reproduce the mechanics of earthquakes at heterogeneous faults. A better understanding of the interaction between stable and unstable fault sections will help us evaluate the potential for extremely large earthquakes that will likely enhance existing seismic hazard assessment tools. This project is a benefit to society because it will help us to better understand earthquakes and develop tools to assess these hazards, and it will add to STEM education of students while supporting new researchers in earthquake studies.This research is a collaborative effort to investigate the mechanics of earthquake rupture arrest with focus on heterogeneous fault properties. It combines multiscale laboratory experiments and numerical modeling. The experiments provide physical constraints for the numerical models, while the modeling improves understanding, generalizing, and scaling up the experimental results. Large-scale laboratory earthquake experiments are conducted on a biaxial machine that generates repeatable sequences of dynamic rupture events contained within a 3-m long granite sample. The fault surfaces are coated with gouge to generate patches of velocity-weakening and velocity-strengthening materials. To explore scaling effects, additional experiments are conducted on a 0.76 m tabletop biaxial machine using plastic samples as forcing blocks. Smaller-scale double-direct shear experiments will benchmark the frictional constitutive parameters of the gouge materials, an essential step for the interpretation of the larger-scale laboratory earthquake observations and the development of realistic, high-resolution numerical models of dynamic rupture and arrest. The simulations include sequences of slip events that quantitatively reproduce the relevant scales of the experiments including the actual size of the apparatus and the rupture process zone.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

摩擦和材料特性沿着构造断层变化，直接影响地震的成核、传播和抑制。自然断层的这种异质性特征使得地震变得复杂且难以预测。有些断层大部分是锁定的，但经常发生地震。其他部分呈蠕变状态，总体稳定。然而，在人们知之甚少的情况下，在不稳定断层中爆发的地震可能会传播到稳定的断层断层，并导致特别大的破坏性事件。该项目通过将大规模实验室地震实验与基于物理的数值模拟相结合，研究导致蠕动断层段激活的原因。建模断层由稳定部分和不稳定部分组成，真实再现了异质断层处的地震力学。更好地了解稳定和不稳定断层之间的相互作用将有助于我们评估特大地震的可能性，这可能会增强现有的地震灾害评估工具。该项目对社会有益，因为它将帮助我们更好地了解地震并开发评估这些危害的工具，并且将增加学生的 STEM 教育，同时支持地震研究的新研究人员。这项研究是一项合作研究，旨在调查地震止裂力学，重点关注异质断层特性。它结合了多尺度实验室实验和数值建模。实验为数值模型提供了物理约束，而建模则提高了对实验结果的理解、概括和扩展。大型实验室地震实验是在双轴机器上进行的，该机器可生成包含在 3 米长花岗岩样本内的可重复的动态破裂事件序列。断层表面覆盖着凿痕，以生成速度减弱和速度增强材料的斑块。为了探索缩放效应，使用塑料样品作为受力块，在 0.76 m 桌面双轴机器上进行了额外的实验。较小规模的双直剪实验将对凿岩材料的摩擦本构参数进行基准测试，这是解释更大规模的实验室地震观测结果以及开发真实的高分辨率动态破裂和停止数值模型的重要步骤。模拟包括滑动事件序列，定量地再现了实验的相关规模，包括设备的实际尺寸和破裂过程区域。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和技术进行评估，被认为值得支持。更广泛的影响审查标准。

项目成果

期刊论文数量（4）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Groove Generation and Coalescence on a Large‐Scale Laboratory Fault

大型实验室断层上的凹槽生成和合并

DOI：
10.1029/2020av000184
发表时间：
2020-10
期刊：
AGU Advances
影响因子：
8.4
作者：
Brodsky, Emily E.;McLaskey, Gregory C.;Ke, Chun‐Yu
通讯作者：
Ke, Chun‐Yu

The earthquake arrest zone

地震阻滞区

DOI：
10.1093/gji/ggaa386
发表时间：
2020-11
期刊：
Geophysical Journal International
影响因子：
2.8
作者：
Ke, Chun;McLaskey, Gregory C;Kammer, David S
通讯作者：
Kammer, David S

Creep fronts and complexity in laboratory earthquake sequences illuminate delayed earthquake triggering

实验室地震序列中的蠕变前沿和复杂性阐明了延迟地震触发

DOI：
10.1038/s41467-022-34397-0
发表时间：
2022-11-11
期刊：
Nature Communications
影响因子：
16.6
作者：
Cebry, Sara Beth L.;Ke, Chun-Yu;Shreedharan, Srisharan;Marone, Chris;Kammer, David S.;McLaskey, Gregory C.
通讯作者：
McLaskey, Gregory C.

Earthquake breakdown energy scaling despite constant fracture energy

尽管断裂能恒定，但地震断裂能仍按比例缩放