article · Energy Geoscience
Geochemical evaluation of the Siwa Basin in Egypt provides new insights into source rock characteristics and the origin of reservoir hydrocarbons. Investigation of Paleozoic formations via well-log data, Rock-Eval pyrolysis, and biomarkers shows varying total organic carbon levels from 0.17 to 2.04 weight percent. The rocks contain both gas-prone Type III kerogen and oil-prone Type II kerogen. Specifically, the Dhiffah Formation includes terrestrial and marine matter in an oxidised setting, whereas the Desouky and Zeitoun formations reflect a more reducing, marine-influenced transitional environment. Analysis of oil samples from five separate wells indicates organic matter deposited under oxidising conditions with prominent marine and terrestrial inputs. These geochemical correlations suggest that oil discovered in the Jurassic Safa reservoir may have originated from deeper Paleozoic source rocks or from the Safa Member itself.
Identifying the precise origins of oil and gas is vital for reducing exploration risks in sedimentary basins. By matching reservoir oils to specific ancient source rock layers, geological teams can better understand how hydrocarbons were generated and where they migrated. This knowledge refines regional geological models, helping geoscientists accurately locate prospective petroleum reserves within under-explored basins.
This research is early-stage geochemical exploration intelligence directly applicable to upstream oil and gas operating companies and energy ministries. Exploration geologists and reservoir engineers can utilise these source-to-oil correlation fingerprints to improve basin modelling and target drilling sites more effectively in the Western Desert. While the findings provide actionable geological insights, further seismic and appraisal work would be required before any commercial drilling decisions are finalised.
AI-generated from the published abstract. Always read the original work before citing.
Understanding the origins of potential source rocks and unraveling the intricate connections between reservoir oils and their source formations in the Siwa Basin (Western Desert, Egypt) necessitate a thorough oil-source correlation investigation. This objective is achieved through a meticulous analysis of well-log responses, Rock-Eval pyrolysis, and biomarker data. The analysis of Total Organic Carbon across 31 samples representing Paleozoic formations in the Siwa A-1X well reveals a spectrum of organic richness ranging from 0.17 wt% to 2.04 wt%, thereby highlighting diverse levels of organic content and the presence of both Type Ⅱ and Type Ⅲ kerogen. Examination of the fingerprint characteristics of eight samples from the well suggests that the Dhiffah Formation comprises a blend of terrestrial and marine organic matter. Notably, a significant contribution from more oxidized residual organic matter and gas-prone Type III kerogen is observed. Contrarily, the Desouky and Zeitoun formations exhibit mixed organic matter indicative of a transitional environment, and thus featuring a pronounced marine influence within a more reducing setting, which is associated with Type II kerogen. Through analysis of five oil samples from different wells—SIWA L-1X, SIWA R-3X, SIWA D-1X, PTAH 5X, and PTAH 6X, it is evident that terrestrial organic matter, augmented by considerable marine input, was deposited in an oxidizing environment, and contains Type III kerogen. Geochemical scrutiny confirms the coexistence of mixed terrestrial organic matter within varying redox environments. Noteworthy is the uniformity of identified kerogen Types II and III across all samples, known to have potential for hydrocarbon generation. The discovery presented in this paper unveils captivating prospects concerning the genesis of oil in the Jurassic Safa reservoir, suggesting potential links to Paleozoic sources or even originating from the Safa Member itself. These revelations mark a substantial advancement in understanding source rock dynamics and their intricate relationship with reservoir oils within the Siwa Basin. By illuminating the processes of hydrocarbon genesis in the region, this study significantly enriches our knowledge base.
This page summarises published work. The authoritative version sits with the publisher.
DOI: 10.1016/j.engeos.2024.100298
Is something wrong with this record? Report it or request removal.
Discussion
Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.
No discussion yet. Open the first thread.
New to MARATTO™? Create a free account.
