Matured continental rift zones that imprint the complete cycle of rifting are rare deformation environments in the globe. The western Afar margin is one that shows such a complete process. This research is aimed to understand the development of the lower part of the western Afar margin and determine the nature of transfer zones that host the mega dike injections, the elliptical scoria cones, and rhyolitic domes around Gulina area. To do so, structural analyses were conducted using intensive field measurements, Landsat ETM+, and SPOT imageries, and digital elevation models (DEM) data to comprehend chronologically distinct structures and magmatic series. The result shows that marginal structures are represented by older rift bounding NNW-SSE trending faults and younger NE-SW oriented transverse structures. Mode of emplacement of these two structurally and chronologically distinct structures are found associated with the evolution of the marginal magmatic series. The study has also investigated NE-SW trending offset faults and NE-SW striking transversal structures. Moreover, this work shows that the marginal structures are inactive but the younger structures (mega dikes and scoria cones are active and controlled by regional transversal structures that separate the Erta’Ale range and Tendaho-MandaHararo rift segment). From the recognition of the cross-cutting relationship, the marginal faults are identified as firstgeneration fractures, whereas the deformed domical silicified rhyolite outcrops situated in the marginal areas are classified under the second generation. The preserved rhyolite dome in the rift floor, the scoria cones, rift floor fractures, and dikes are found to be third-generation structures.

印有完整裂谷周期的成熟大陆裂谷带是全球罕见的变形环境。阿法尔西部边缘就是这样一个完整的过程。本研究旨在了解阿法尔边缘西部下部的发育，并确定承载巨型堤防注入、椭圆形火山渣锥体和古利纳地区周围流纹质圆顶的转移带的性质。为此，使用密集的现场测量、Landsat ETM+ 和 SPOT 图像以及数字高程模型 (DEM) 数据进行结构分析，以了解按时间顺序排列的不同结构和岩浆系列。结果表明，边缘结构以较老的裂谷边界 NNW-SSE 向断层和较新的 NE-SW 向横向结构为代表。发现这两种结构和年代不同的结构的就位方式与边缘岩浆系列的演化有关。该研究还调查了 NE-SW 趋势偏移断层和 NE-SW 突出的横向结构。此外，这项工作表明边缘构造不活跃，但较年轻的构造（巨型岩脉和火山渣锥活跃，并由分隔 Erta'Ale 山脉和 Tendaho-MandaHararo 裂谷段的区域横向构造控制）。从横切关系的认识上，边缘断层被确定为第一代裂缝，而位于边缘区域的变形的穹顶硅化流纹岩露头被归类为第二代。裂谷中保存完好的流纹岩圆顶，火山渣锥，