The Source Rock Evaluation and Hydrocarbon Potential of the Cretaceous Rocks from Chalbi Basin, Block 10a of the Anza Rift based on Lopatin–Waples Method

Abstract

The Anza Rift is a northwest-southeast trending sedimentary basin located in northern Kenya. This is one of the remaining underexplored frontier exploration areas possessing high potential in hydrocarbon discoveries considering its proximity to the proliferous petroleum regions of South Sudan and Turkana.

Only four exploration wells that include Chalbi-3, Bellatrix-1, Sirius-1 and Paipai-1, that have been drilled over the Chalbi subbasin with some well sections reported to contain oil and gas indications, thus suggesting the presence and development of a working Petroleum system. Based on the available regional gravity and magnetic data, the thicknesses of this sedimentary infill vary in the range of 7-9 km. The drilled well sections demonstrated good reservoir rock properties with good to fair porosities values of between 10 - 30%. Fairly much is known about the source rock potential of the Anza Basin.

This research focuses on the evaluation of the source rock maturation, hydrocarbon potential and the interpretation of families of burial history curves and Time-Temperature Indexes obtained from three exploration wells, namely, Sirius-1, Bellatrix-1 and Chalbi-3 from the southern part of the Chalbi sub-basin through the application of the Lopatin –Waples technique. Despite the absence of commercial oil and gas discoveries in the Anza Rift, the obtained results provide positive indications for future exploration and finding of normal to normal-light oil deposits in the North West part of the sedimentary basin.