The potential for CO2 disposal in Harrat Rahat and other volcanic fields in the Arabian Peninsula

This paper assesses the possibility of in-situ CO 2 mineralization in the Oligocene-Holocene basalt lava fields in the Arabian Peninsula. We consider the application of two methods: the injection of CO 2 dissolved in water (Carbfix method) and the injection of supercritical CO 2 . Both methods require thick water-saturated basalt aquifers exceeding 400 m and 800 m in thickness, respectively. A total of 23 basalt fields were mapped and evaluated for CO 2 disposal by either method. The basalt fields are distinguished into an older (30-14 Ma) generation of dissected fields, forming mesas above the Arabian Plateau, and a younger (14-0 Ma) generation of relatively uneroded fields. Most consist of unaltered basalts, which locally exhibit natural carbonation by calcite precipitation in fractures. The volcanic fields were fed by monogenetic volcanoes along four major trends, which vary from NNW to ENE. The thickness of each lava field and its groundwater aquifer height were estimated based on its geologic and topographic setting using a digital elevation model. This study found that most of the lava fields are not suitable for CO 2 disposal because the basalts are either too thin or are located higher than the groundwater table. However, there are areas in Harrat Rahat and the Yemen Traps that contain sufficient basalt thickness and groundwater aquifers for CO 2 mineralization. This study presents an approach for evaluating CO 2 disposal potential on basalt fields in desert regions. Results are expected to facilitate industrial-scale CO 2 disposal in the volcanic fields of the Arabian Peninsula and elsewhere.