美国爱荷华州立大学Jacqueline E. Reber团队近日取得一项新成果。他们的研究利用地貌指纹识别断层滑动行为的变化。相关论文于2024年8月20日发表于国际顶尖学术期刊《地质学》杂志上。

据介绍，Gabilan山从加利福尼亚中部的圣安德烈斯断层向西南缓慢倾斜。研究人员认为，这种大型地貌的形成是对圣安德烈斯断层滑动行为变化的响应，而不是归因于板块汇聚。该解释是基于本研究物理实验的结果。

实验过程中，当研究人员将滑动行为的变化(即从迟缓到锁定)作为影响变形的唯一变量时，在滑动过渡处形成半穹顶特征，模仿了与圣安德烈斯断层相邻的Gabilan山的形状和位置。研究人员还展示了北安那托利亚(土耳其)、菲律宾和查曼(阿富汗-巴基斯坦)断层的其他半穹顶特征，表明这些穹顶地貌可能提供了在监测不足的断层上滑动行为转变的迹象。

附：英文原文

Title: Using a landscape fingerprint to identify changes in fault-slip behavior

Author: Emily O. Ross, Jacqueline E. Reber, Sarah J. Titus, Antonio F. García

Issue&Volume: 2024-08-20

Abstract: The Gabilan mesa tilts gently southwest away from the San Andreas fault in central California (western United States). Rather than attributing its existence to plate convergence, we argue that this large landform developed in response to a change in slip behavior along the San Andreas fault. Our interpretation is based on results from physical experiments. When we isolate a change in slip behavior (i.e., creeping to locked) as the only variable influencing deformation, a half-dome feature forms alongside the slip transition and mimics the shape and location of the Gabilan mesa adjacent to the San Andreas fault. We show other examples of half-dome features along the North Anatolian (Turkey), Philippine, and Chaman (Afghanistan-Pakistan) faults, suggesting that these domed landforms may provide indications of slip behavior transitions on poorly monitored faults.

DOI: 10.1130/G52156.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G52156.1/646746/Using-a-landscape-fingerprint-to-identify-changes