意大利佛罗伦萨大学Daniele Maestrell的团队报道了在裂谷-裂谷-裂谷三联结处对板块运动和断裂进行调和。2024年2月23日，国际知名学术期刊《地质学》发表了这一成果。

该研究团队使用一个模拟模型来补充这些观察结果，以深入了解断层的模式和方向与整体板块运动相关联系。在模型和自然界中的一个关键发现是，一些相邻的正断层以高角度形成并形成T形构造。研究表明，这些纯正断层是同步活动的，这意味着其局部伸展方向变化约90°。

尽管整体表面运动模式相对平稳，但研究使用的模型和自然形成的仍存在运动学差异。结果表明，正断层以高角度相互作用形成T型构造，在一个大小变化平缓但方向在几公里范围内变化剧烈的应力场中，可以同步演化。

据了解，裂谷-裂谷-裂谷三联结是三个板块相互作用的区域，形成了复杂的多向断层网络。虽然断层网络的几何形状很容易受到其表面表现的限制，但仍然不清楚的是断层的运动学及其相互作用如何在空间上变化，以及它们与三个板块相互分离导致的异常地壳运动之间的关系。阿法尔凹陷位于非洲、阿拉伯和索马里板块(非洲之角)的三重交界处，在这里，来自构造测绘、地震活动和全球导航卫星系统(GNSS)的观测数据的独特组合，使得研究人员能够了解断层运动学和板块运动之间的联系。

附：英文原文

Title: Reconciling plate motion and faulting at a rift-rift-rift triple junction

Author: Daniele Maestrelli, Federico Sani, Derek Keir, Carolina Pagli, Alessandro La Rosa, Ameha Atnafu Muluneh, Sascha Brune, Giacomo Corti

Issue&Volume: 2024-02-23

Abstract: Rift-Rift-Rift triple junctions are regions where three plates interact, generating complex networks of variably oriented faults. While the geometry of the fault networks is easily constrained from their surface expression, what remains unclear is how the kinematics of faults and their interactions vary spatially, and how these relate to the unusual crustal motions that result from three plates diverging from each other. The Afar depression lies at the triple junction between the African, Arabian, and Somalian plates (in the Horn of Africa), where the unique combination of observational data from structural mapping, seismicity, and Global Navigation Satellite System (GNSS) allows us to understand the link between fault kinematics and plate motions. We complement these observations with an analog model to gain insights into how the patterns and directions of faults relate to overall plate motions. A key finding in both the model and nature is that some adjacent normal faults form at high angles and generate T-shaped structures. These purely normal faults are synchronously active, which means that the extension direction varies ～90° locally. These kinematic contrasts in our model and in nature occur despite the relatively smooth pattern of overall surface motions. The results indicate that normal faults interacting at high angles to form the T-shaped structures can evolve synchronously within a stress field that varies gently in magnitude but dramatically in orientation over a few kilometers.

DOI: 10.1130/G51909.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article-abstract/doi/10.1130/G51909.1/635503/Reconciling-plate-motion-and-faulting-at-a-riftredirectedFrom=fulltext