+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Unlocking STOIIP of Permian Gharif clastic reservoirs in central Oman

Unlocking STOIIP of Permian Gharif clastic reservoirs in central Oman

GeoArabia (Manama) 13.1: 182

The Permian Gharif reservoirs of central Oman represent one of the major producing hydrocarbon reservoirs with significant remaining upside potential locked in lowrelief structural/stratigraphic traps. The Sadad field, which was discovered in 1986 and brought on stream in 1990, is a low-relief anticline (c. 45 m vertical closure and approximately 100 square km areal closure) located about 30 km to the west of the Mukhaizna field in central Oman. The oil is produced from the Upper Gharif, which comprises a terrestrial succession of arid, fluvial deposits contained within a predominantly muddy floodplain, resulting in a relatively low net/gross of about 30%. The oil is 24o API with a viscosity of 42 cP. Initial development of the Sadad field until 1998, was based on the drilling of high-angle, deviated wells that aimed to penetrate the reservoir both laterally and vertically. This proved largely unsuccessful and cost-intensive due to the low success rate of finding producible reservoir within the highly heterogeneous Upper Gharif Member. Thus, a new development strategy was instilled, comprising multiple cost-effective, vertical wells (peepholes) that could tolerate the expected low success rate and improve the understanding of the reservoir model to reduce uncertainty in targeting productive sand trends. The first peephole campaign of 20 wells was drilled in 2001 with a success rate of 60% resulting in a production increase. The second peephole campaign drilled another 12 wells and netted a success rate of 66%. Both campaigns achieved the economic and geological success criteria from the peepholes. Several marginal discoveries were also made on similar low relief structures around the Sadad Field in the early 80's with a single well. Many of these discovery wells were not tested due to poor perceived net/gross, despite good oil shows. Using the Sadad analogue, it could be interpreted that these single wells do not represent the potentially high oil-in-place (STOIIP) of these accumulations, and so warrant further investigation. Additional peephole drilling and possible 3-D seismic acquisition are proposed to support the search for more Gharif oil in central Oman. (Publisher extract)

Please choose payment method:

(PDF emailed within 1 workday: $29.90)

Accession: 037195425

Download citation: RISBibTeXText

Related references

Early Permian alluvial Gharif Formation reservoirs of central Oman. Annual Meeting Abstracts - American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists 1992: 76-77, 1992

Applications and pitfalls of stochastically built static model realizations on reservoir characteriztion and STOIIP distribution of clastic reservoirs of southern Oman oil fields. GeoArabia (Manama) 13.1: 209, 2008

Seeking new potential in the Early-Late Permian Gharif Play, west central Oman. AAPG Bulletin: , Pages 1218-1219. 1995., 1995

A new ostracod Crustacea species Geffenina wangi from the Middle Permian of Jebel Gharif central Oman. Journal of Micropalaeontology 22, Part 1(Pages 101-105, 2003

Changing sand provenance in the Permian Gharif Formation of central Oman; results of a pilot heavy mineral study. GeoArabia (Manama): Pages 127. 2000., 2000

Early Permian cladid crinoids from the Gharif Formation of Oman. Memoir of the Association of Australasian Palaeontologists: ages 305-312. 1993., 1993

Reservoir evaluation of the Permian Gharif Formation, Sultanante of Oman. Proceedings - Middle East Oil Show Pages 517-528, 1989

Spores and pollen from the middle and upper Gharif Members Permian of Oman. Palynology 32, 2008

Two new non-haptotypic palynomorph taxa from the Middle Permian Upper Gharif Member, Oman. Rivista Italiana di Paleontologia e Stratigrafia 117.2, 2011

The Oman Gharif mixed paleoflora: A useful tool for testing Permian Pangea reconstructions. Palaeogeography Palaeoclimatology Palaeoecology 196(1-2): 85-98, 15 July, 2003

Diagenesis and pore-water evolution in Permian sandstones, Gharif Formation, Sultanate of Oman. Journal of Sedimentary Research 70(3): 533-544, 2000

Allostratigraphy, a practical solution to the Gharif/Khuff boundary discrepancies in the Lower Permian of Oman. Newsletters on Stratigraphy 35(2): 83-95, 1997

Palynology of the deglaciation sequence represented by the Lower Permian Rahab and Lower Gharif members, Oman. AASP Contributions Series. December; 40 i-iv, 1-48, 2002

The Permian Gharif Formation, Oman; development of a high-resolution sequence stratigraphic framework and implications for the paleogeographic evolution of a transgressive-regressive depositional system. GeoArabia (Manama) 5(1): 118, 2000

Sedimentology and reservoir geometry of the Upper Permian upper Gharif and lower Khuff formations in interior Oman; outcrop study in the Haushi area. GeoArabia (Manama) 3(1): 82-83, 1998