The Aluto–Langano geothermal field is located within the central-southern part of the Main Ethiopian Rift, about 200 km southeast of Addis Ababa. This study analyzes gravity data to define the geometry of the geothermal reservoir and subsurface geological structures controlling the geothermal system. A Bouguer anomaly map of the area was generated using a Bouguer density of 2.49 g/cm³, which was obtained from the gravity dataset using different optimization methods. In order to highlight the structures of interest in the calderic system, a regional-residual separation was conducted. The map produced shows two dominant high Bouguer anomalies underlying Aluto caldera associated with the presence of basaltic rocks and the occurrence of fumarolic activity. Analysis of horizontal gradients of gravity data showed that the area is characterized by the presence of high gradient anomalies associated with geothermal manifestations. A 3-D gravity model for assessing the geothermal heat source architecture within the Aluto caldera area is also presented. The model was constrained using the estimated densities of rock cuttings obtained from drilled wells. The results from 3-D modeling imaged a high-density body at depth surrounded by a less-dense body (∼2.55 g/cm³), which is interpreted to be the geothermal reservoir. The model was then interpreted together with surface manifestations, lithology, and geological structures. The less-dense body found west of the Adonsha fault lineament could be the expression of the second reservoir, which is likely deeper than the productive reservoir found along the NNE–SSW trending structure (i.e., the Artu Jawe Fault Zone) in the central area.

Aluto-Langano地热田位于埃塞俄比亚主裂谷的中南部，在亚的斯亚贝巴东南约200公里处。这项研究分析了重力数据，以定义地热储层的几何形状和控制地热系统的地下地质结构。使用2.49 g / cm ³的布格密度生成该区域的布格异常图。，它是使用不同的优化方法从重力数据集获得的。为了突出在破火山口系统中感兴趣的结构，进行了区域-残留分离。生成的地图显示了Aluto破火山口下方的两个主要的高布格异常，与玄武岩的存在和富马活动有关。对重力数据的水平梯度的分析表明，该地区的特征是存在与地热表现有关的高梯度异常。还介绍了用于评估Aluto破火山口区域内的地热热源结构的3-D重力模型。使用从钻井获得的估计岩屑密度来约束该模型。³），这被解释为地热储层。然后将模型与表面表现，岩性和地质结构一起解释。在Adonsha断层系西部发现的密度较小的体可能是第二个储集层的表达，它可能比在中部地区NNE-SSW趋势构造（即Artu Jawe断层带）上发现的生产性储集层更深。 。