A petroleum geologist and research scientist studying petroleum systems in Kansas, USA, Oluwaseun Omoyemi, has highlighted geological uncertainties as a major challenge to petroleum exploration in Nigeria’s Chad Basin.
She noted that hydrocarbon exploration has been ongoing in the Chad Basin of Nigeria for over 45 years without success, despite discoveries and production in Chad and Niger Republics. According to her, the Nigerian sector of the basin is characterized by significant geological uncertainties that hinder exploration efforts.
Drawing from her ongoing research on petroleum systems, Omoyemi identified key geological factors that may be limiting exploration success in the Chad Basin.
Omoyemi explained: “The Chad Basin, much like parts of Kansas, exhibits variations in sedimentary deposition, reservoir quality, and source rock maturity “Understanding these elements is crucial to assessing petroleum potential and mitigating exploration risks.”
One of the major challenges is uncertainty in source rock distribution and thermal maturity. Omoyemi’s research in Kansas demonstrated that even in well-studied basins, variations in organic content and burial history can significantly affect oil and gas generation.
“In the Chad Basin, limited well data and subsurface imaging make it difficult to accurately map these variables,” she noted.
Additionally, Omoyemi pointed to geochemical uncertainties in petroleum systems, even in Kansas, where production has continued for over 50 years. She advocated for extensive geochemical analysis of rock samples from drilled wells. This includes gas chromatography and gas chromatography-mass spectrometry analyses of potential source rocks such as the Fika Shales and the Gongila Formation.
According to her, results from such analyses can provide crucial insights into source rock potential, hydrocarbon typing, and migrated hydrocarbons, improving the chances of discovering commercially viable hydrocarbon accumulations.
Another major factor contributing to exploration challenges is structural complexity.
Omoyemi stated: “Faulting and basin subsidence patterns influence hydrocarbon migration pathways and trap formation.
“In Kansas, extensive seismic studies helped clarify structural traps and delineate sub-basins. However, in the Chad Basin, data gaps remain a challenge.”
She emphasized that while 3D and 4D seismic imaging are now industry standards for detailed subsurface characterization, only 2D seismic data are currently available for the Chad Basin, limiting exploration accuracy.
Despite these uncertainties, Omoyemi remains optimistic about the Chad Basin’s petroleum prospects.
“With advancements in seismic imaging and geochemical modeling, we can improve our understanding of the petroleum system and reduce exploration risks,” she stated. “Interdisciplinary research and regional analogs—such as those in Kansas—offer valuable insights that could be the key to unlocking hydrocarbons in Nigeria’s Chad Basin.”
As exploration efforts continue, Omoyemi’s analysis underscores the need to integrate geological, geophysical, and geochemical data to navigate the complexities of frontier petroleum basins.
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