Integrated G&G and Engineering Assessment of a Remarkable Cretaceous Discovery in Bahrah Field at North Kuwait

Abstract

Comprehensive and fully-integrated analyses were performed on the first discovery in Zubair formation of lower Cretaceous age at Bahrah field in North Kuwait with objective of assessing HC potential, well performance, reservoir characteristics and verify connectivity between reservoir flow units. Based on petro-physical evaluation of OHL, bottom-hole samples, and RDT pressure points two flow units within Zubair reservoir were identified. The OHL showed that these two zones are separated by thin shale strikes additionally; the resistivity against the upper zone showed possibility of being water. Therefore, it was decided to test the two reservoir units separately. Subsequently, after two successful production tests, analyses of well production performance including Nodal Analysis, PVT, RDT and PTA were carried out for both zones in order to assess reserve potential, obtain essential reservoir rock & fluid characteristics and verify vertical connectivity. Remarkable oil discovery was made in Zubair reservoir of Bahrah field with substantial addition of proven reserves and commercial production potential, which will definitely support achieving the strategic production target. In order to verify long-term production sustainability, Extended Well Testing (EWT) was conducted. The results showed that this reservoir is capable to produce Hydrocarbon in a sustainable manner. Production Performance, PVT, RDT, PTA and Nodal analysis results showed that the two tested zones in Zubair reservoir are interconnected with same fluid characteristics and it can be considered as one reservoir even though the open-hole logs responses showing that they could be different reservoirs. This paper will present detailed comprehensive engineering and geological analyses of first Zubair oil discovery in Bahrah Field at North Kuwait. All available structural, petrophysical, PVT and production information were used to develop static model by Petrel-RE and subsequently, detailed data acquisition, appraisal drilling and conceptual field development plans have been established.