Collaborative Research: Implications of Active Tectonics in Morocco for the Kinematics and Dynamics of Africa-Eurasia Plate Interactions in the Western Mediterranean

该项目利用全球定位系统(GPS)重复观测和干涉合成孔径雷达(InSAR)监测与非洲板块与伊比利亚(欧亚)大陆持续“碰撞”有关的摩洛哥活动形变。此外，新构造和古地震研究正在帮助更好地确定持续变形、地震发生和地质结构发展之间的关系。为此，调查人员正在升级三个连续的全球定位系统(CGPS)站(拉巴特、特图安、伊福雷)，并在阿加迪尔附近建立一个新的CGPS站。这些台站提供了对非洲(努比亚)板块运动的高精度估计，以及对板内变形的强烈限制，包括预期的跨越摩洛哥中部阿特拉斯山脉的缩短。此外，摩洛哥的CGPS网络提供了一个框架，用于整合测量模式的GPS观测，这种观测提供密集的覆盖范围，以隔离单独的活动结构。正在用古地震技术研究地震间形变(由GPS和InSAR记录)与地震周期之间的关系。我们工作的一个主要焦点是摩洛哥西北部的Rif山脉，它相对于整个非洲板块表现出快速的西南运动。GPS和InSAR测量更好地定义了这些异常运动的特殊和时间特征。利用改进的变形结果，正在开发检验挤压模型(地壳被挤出碰撞带)以及与地幔动力学过程(活动俯冲、岩石圈拆沉)相关的地壳变形模型的定量模型。

This project is using Global Positioning System (GPS) repeat observations, and Interferometric Synthetic Aperture Radar (InSAR) to monitor active deformation in Morocco associated with ongoing "collision" of the African plate with Iberia (Eurasia). Additionally, neotectonic and paleoseismic studies are helping better determine the relation between ongoing deformation, earthquake generation, and the development of geologic structures. Toward these ends, the investigators are upgrading three continuous GPS (CGPS) stations (Rabat, Tetouan, Ifrane) and establishing a new CGPS station near Agadir. These stations provide highly precise estimates of Africa (Nubia) plate motion as well as strong constraints on intraplate deformation, including anticipated shortening across the Atlas Mountains in central Morocco. In addition, the Moroccan CGPS network provides a framework for integrating survey-mode GPS observations that provide dense coverage to isolate individual, active structures. The relationship between interseismic deformation (as recorded by GPS and InSAR) and the earthquake cycle are being investigate with paleoseismic techniques. A major focus of our work is the Rif Mountains in northwestern Morocco that exhibit rapid SW motions relative to the African plate as a whole. GPS and InSAR measurements are better defining the special and temporal character of these anomalous motions. Using the improved deformation results, quantitative models to test extrusion models (crust being squeezed out of the collision zone) as well as models of crustal deformation associated with dynamic processes in the mantle (active subduction, lithospheric delamination) are being developed.