000			02527nab a2200205 4500
005			20260520002148.0
008			260224s2019 xxu ing
041			_aInglés
245	0	0	_aPetroleum geology of the Nogal basin surrounding area, northern Somalia, Part 2: Hydrocarbon potential
260			_a _b _cjul. 2019
270			_a26/07/2019 ; 25/07/2019
300			_a27 p. ; 233-260
520			_aTranscripción del resumen del autor: Seismic reflection profiles and well data show that the Nogal Basin, northern Somalia, has a structure and stratigraphy suitable for the generation and trapping of hydrocarbons. However, the data suggest that the Upper Jurassic Bihendula Group, which is the main source rock elsewhere in northern Somalia, is largely absent from the basin or is present only in the western part. The high geothermal gradient (~35-49 oC/km) and rapid increase of vitrinite reflectance with depth in the Upper Cretaceous succession indicate that the Gumburo Formation shales may locally have reached oil window maturity close to plutonic bodies. The Gumburo and Jesomma Formations include high quality reservoir sandstones and are sealed by transgressive mudstones and carbonates. 1D petroleum systems modelling was performed at wells Nogal-1 and Kalis-1, with 2D modelling along seismic lines CS-155 and CS-229 which pass through the wells. Two source rock models (Bihendula and lower Gumburo) were considered at the Nogal-1 well because the well did not penetrate the sequences below the Gumburo Formation. The two models generated significant hydrocarbon accumulations in tilted fault blocks within the Adigrat and Gumburo Formations. However, the model along the Kalis-1 well generated only negligible volumes of hydrocarbons, implying that the hydrocarbon potential is higher in the western part of the Nogal Basin than in the east. Potential traps in the basin are rotated fault blocks and roll-over anticlines which were mainly developed during Oligocene–Miocene rifting. The main exploration risks in the basin are the lack of the Upper Jurassic source and reservoirs rocks, and the uncertain maturity of the Upper Cretaceous Gumburo and Jesomma shales. In addition, Oligocene–Miocene rift-related deformation has resulted in trap breaching and the reactivation of Late Cretaceous faults.
581			_a3
773	0		_tJournal of Petroleum Geology _g
942			_cARTICULO
100	1		_aAli, M.Y. _940271
100	1		_aLee, J.H. _934812
999			_c193096 _d193096