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GEO 2008 Conference Abstracts, Bahrain GEO 2008 Conference Abstracts GEO 2008 conference abstracts, Bahrain GEO 2008 Conference Abstracts he abstracts of the GEO 2008 Conference presentations (3-5 March 2008, Bahrain) are published in Talphabetical order based on the last name of the first author. Only those abstracts that were accepted by the GEO 2008 Program Committee are published here, and were subsequently edited by GeoArabia Editors and proof-read by the corresponding author. Several names of companies and institutions to which presenters are affiliated have been abbreviated (see page 262). For convenience, all subsidiary companies are listed as the parent company. (#117804) Sandstone-body geometry, facies existing data sets and improve exploration decision architecture and depositional model of making. The results of a recent 3-D seismic reprocessing Ordovician Barik Sandstone, Oman effort over approximately 1,800 square km of data from the Mediterranean Sea has brought renewed interest in Iftikhar A. Abbasi (Sultan Qaboos University, Oman) deep, pre-Messinian structures. Historically, the reservoir and Abdulrahman Al-Harthy (Sultan Qaboos targets in the southern Mediterranean Sea have been the University, Oman <[email protected]>) Pliocene-Pleistocene and Messinian/Pre-Messinian gas sands. These are readily identifiable as anomalousbright The Lower Paleozoic siliciclastics sediments of the amplitudes on the seismic data. The key to enhancing the Haima Supergroup in the Al-Haushi-Huqf area of cen- deeper structure is multiple and noise attenuation. The tral Oman are subdivided into a number of formations Miocene and older targets are overlain by a Messinian- and members based on lithological characteristics of aged, structurally complex anhydrite layer, the Rosetta various rock sequences. One of the distinct sandstone Formation. This layer is of variable thickness and is sequences, the Barik Sandstone (Late Cambrian-Early highly fractured in places. The quality of seismic data Ordovician) of the Andam Formation is a major deep beneath it tends to be inversely proportional to the thick- gas reservoir in central Oman. The sandstone bodies are ness and complexity of the layer. The Rosetta Formation the prospective reservoir rocks, whereas thick shale and also generates a significant amount of complex multiple clay inter-beds act as effective seals. Parts of the Barik energy. On the seismic data, these multiples are not well Sandstone, especially the lower and middle parts, are defined. Many methods of multiple attenuation are exposed in isolated outcrops in the Al-Haushi-Huqf area therefore only partially successful, and the residual mul- as inter-bedded, multi-storied sandstone, and green and tiple often appears as a fuzz of noise on near and middle red shale. The sandstone bodies are generally up to 2.0 offsets. Attenuation of this residual multiple noise was m thick and can be traced laterally for a few hundred one of the keys to the success of the reprocessing effort. metres to a few kilometres. Most of the sandstone bodies This presentation outlines a carefully executed process- show both lateral and vertical amalgamation. Two types ing flow to enhance the signal-to-noise ratio and im- of sandstone facies are identified on the basis of field re- prove the time imaging for the pre-Messinian structures lationship: (1) a white sandstone facies usually capping in the southeast Mediterranean Sea. The success of the thick red and green shale beds; and (2) a brown cross- reprocessing meant that acreage that was due to be re- bedded sandstone facies overlying the white sandstone linquished was extended, and is now a location for new facies. An attempt was made to study the relationship of seismic activity and possibly, new drilling. fluvial, fluvio-deltaic and tidal processes on the basis of lithofacies characteristics. This presentation summarizes the results of a preliminary study carried out in the Al- (#117249) Organic geochemical evaluation Haushi-Huqf area to analyze the characteristics of the of the Lower Cretaceous Minagish Reservoir sandstone-body geometry, internal architecture, prov- Formation in Kuwait enance and diagenetic changes in the lower and middle parts of the member. Fowzia Hussein Abdullah (Kuwait University <[email protected]>) and Suad AbdulKareem Qabazard (Kuwait University (#119029) Offshore Mediterranean seismic <[email protected]>) data processing challenges The Lower Cretaceous Minagish Formation is one of the Magdy AbdelAty (WesternGeco, Egypt major oil reservoirs in southern Kuwait. The middle oo- <[email protected]>), Tamer Saleh (WesternGeco, litic member is the main reservoir interval and is capped Egypt), Michael Cogan (WesternGeco, Egypt <cogan1@ by the upper carbonate mudstone member. The reser- slb.com>), Alfredo Cegna (Eni, Egypt), Antonio Betti voir is productive in the Burgan, Minagish, Mutriba and (Eni, Egypt), Giorgio Bondi (Eni, Egypt) and Bahra fields in Kuwait, and in the Wafra, South Fawaris, Riccardo Vercesi (Eni, Egypt) Hout and Dorra oil fields in the Kuwait-Saudi Arabia Partitioned Neutral Zone. The specific gravity of the The application of a modern processing sequence that Minagish-reservoired oil ranges from 28o to 33.4o API and focuses on noise and multiple attenuation demonstrated the average sulfur concentration is 2.6%. The reservoir in how careful reprocessing can add significant value to 99 Downloaded from https://pubs.geoscienceworld.org/geoarabia/article-pdf/4570307/geo2008abstracts.pdf by UNIVERSITA DEGLI STUDI DI MILANO user on 27 July 2020 GEO 2008 conference abstracts, Bahrain the Minagish field contains a 50–100-ft-thick tarmat and improve the sweep efficiency. The flank areas of the res- very high-density oil at the base of the oil column. This ervoir with inferior flow properties and heavier oil are interval has blocked the base of the reservoir and caused being strategically developed. Seismic attribute analysis, a decrease in reservoir pressure. An understanding of zonal testing and fluid characterization from advanced the nature and composition of the oil column throughout logging techniques are being used to delineate these the reservoir may identify zones of low- and high-den- areas. This presentation will discuss a multi-pronged sity oil, as well as tarmat and pyrobitumen. Applying strategy of mapping reservoir heterogeneity and its use this analysis may help in production and enhancing in optimal field development. oil recovery. The analysis can be conducted by using organic geochemical methods applied on rock samples or oil in the formation. The purpose of this study is to (#118698) Partnering to develop a national evaluate the nature of the hydrocarbons in the Minagish workforce: Practical challenges and solution Formation using the Rock Eval-Reservoir method as one Mohamed S. AbouSayed (ResModTec <mgsalah@ of the tools to identify zones of heavy and light hydro- resmodtec.com>) carbon zones. It is anticipated to show the homogeneity of the hydrocarbon along the reservoir, both vertically The challenges facing the Middle East region include and horizontally. A total of 72 core samples were col- increasing the oil production capacity and ageing of the lected from four oil fields in southern Kuwait; Burgan, production facilities. To meet these challenges we must Magwa, Minagish and Umm Gudair fields. They will be have a national workforce capable of achieving these analyzed using the above method and the results will be goals. The creation and subsequent development of this tabulated. Calculations will be carried-out on the result national workforce is not an easy task. This presentation to identify the nature of hydrocarbons along each of the concentrates on the practical challenges that face all na- study well. tional oil companies in the region and how to overcome them so as to develop the required local force that can deal with the industry’s technical challenges. The pre- (#117808) Reservoir heterogeneity and senter has trained more than 2,500 geoscientists and development strategy of the Mauddud engineers from the entire region since 2004.The analysis Reservoir undergoing pattern water flooding of these short and long-term training sessions has led to in Raudhatain field, northern Kuwait the identification of some barriers to build this national workforce; for example: English language skills, sequen- Shaikh Abdul Azim (KOC <[email protected]>), tial courses without on-job-training, early jump toward Ashok K. Pathak (KOC), Yahya Hassan (KOC), Ragab software-learning before walking through the technical Shehab (BP, Kuwait), Krenek Ron (BP, Kuwait) and basics, the wrong person in the wrong course, course Hamad Al-Ajmi (KOC) contents, unqualified instructors, student’s aptitude The Albian Mauddud Formation contains a giant car- and attitude and non-technical culture. The solutions bonate reservoir in the Raudhatain field. It has a pro- to these obstacles include updating the course contents, duction history of 45 years, divided into two phases: using local examples, improving the work ethic of local production from depletion drive for the first 40 years employees, training them on character and not only followed by inverted 9-spot pattern injection. During the technical skills, involving supervisors more with par- first phase the reservoir pressure dropped close to the ticipants, using domestic experts as teachers, increasing bubble point with less than 3.0% recovery. The reservoir the cooperation between academia and operating com- has no aquifer support and the reservoir properties dete- panies, and making sure the right attendee is in the cor- riorate towards the flank and to the bottom. The analysis rect course. The Middle East contains 67% of the proven of static and dynamic data has brought-out the inherent world oil reserves. It has a talented and young genera- heterogeneity of the reservoir. On a macro-scale, faults tion and owns the technology to make it happen. What act both as baffles and conduits to fluid flow. Reservoir we need to do is to walk the talk. layers show distinct variation in flow properties, both areally and vertically. The uppermost producing layer (#117418) Early to late diagenetic is more productive towards the flank of the field.
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