Sedimentology And Reservoir Geology Of The Blue Nile Rift Basin

Abstract

three major lithofacies types are siliciclastic sediments and much halite sediment. These are Fluvial, Lacustraine and Deltaic environment. Well logs, ditch and core samples used in the investigations of reservoir formations proved that the sediment facies are similar of the entire region. These facies are the lacustrine facies in most of Blue Nile Formation, and fluvial facies. which are prevailed of Dinder Formation, whereas Deltaic is represent in Damazin and Dinder (1) Formations. The clay minerals of kaolinite and illite have vast and high content in the field, these inferring the conditions of environment, probably intense of chemical weathering and leaching processes under warm humid climate. The presence of smectite suggests that the warmhumid climate was inten'upted by dry seasons as well as the presence of much iron oxide. The presence of illite in the lower zone in a big a mount indicates the transition by (illitization process); transition from smectite and chlorite to illite in the burial depths by effects of tectonism and diagenesis. ‘ . The paleoclimatic interpretation from the clay minerals association and abundances revealed that the central Sudan regions have practiced a hot and dry climate in the Late Jurassic, and a climate with short wet and longer dry seasons in the Early Cretaceous time. - The resen/oir study revealed a significant presence of hydrocarbon as oil. The investigation of well logs in Hosan-1 well revealed that Dinder (2) Formation has mainly gas hydrocarbon. This result was based on interpretation of Neutron and Density logs and has high reading of resistivity log in this zone. _ The investigation of petrophysical of the formation pressure measurement in Hosan-1 well determined Gas Water Contact (QWC) point in two cross lines between water values and gas values plotted. This helped in interpreting the extension of hydrocarbon reservoir zone.