Preliminary investigation of the hydrocarbon generation potential from the post-rift Abbas shale Formation (Pliocene) in the Tihamah Basin, south-eastern Yemeni Red Sea

Pliocene shales included in the post-rift Abbas Formation were recovered from an exploratory well (Kathib-01) in the Tihamah Basin and geochemically analyzed. A preliminary evaluation of the organic facies of the Abbas shales and their petroleum generation potential was conducted based on basic organic geochemical results. Most Abbas shale samples had total organic carbon (TOC) contents < 1% and a fair source potential, while the remaining samples, with TOC contents > 1%, had a relatively good potential. Overall, the Rock-Eval hydrogen index values of the shales analyzed were between 96 and 234 mg of hydrocarbon per gram of TOC (mg HC/g TOC), indicating two dominant organic facies: types III and II/III kerogen, which indicate the presence of mainly gas- and oil-prone source rocks. We conclude that the Pliocene Abbas shales in the Tihamah Basin are still in a very early-mature stage (with respect to the oil window) and, hence, have not generated petroleum yet.

Automated summary

Geochemical analysis of Pliocene Abbas shales in the Tihamah Basin indicates a fair to relatively good petroleum generation potential, with Rock-Eval hydrogen index values suggesting the presence of gas- and oil-prone source rocks. However, the shales are still in a very early-mature stage and have not yet generated petroleum.