Panoro Energy announced an oil discovery in the Ruche North East Marin-1 well offshore Gabon. The 1 well was drilled to identify additional oil resources in the presalt Gamba and Dentale Formations in the greater Ruche Area, and completed within budget. These resources may be developed together in the future with the existing Ruche field discoveries made by Panoro in 2011 and located 3 km to the southwest. Drilled with the Borr Norve jackup unit in 115-m water depth, the well reached a vertical depth of 3400 m within the Dentale Formation. Log evaluation, pressure data, and fluid samples indicate that approximately 15 m of good-quality oil pay was encountered in the Gamba Formation and 25 m of oil pay in stacked reservoirs within the Dentale Formation.
Africa (Sub-Sahara) Vaalco Energy started oil production from the Etame 12-H development well offshore Gabon. The well was drilled to a measured depth of approximately 3450 m and was targeting the recently discovered lower lobe of the Gamba reservoir. It was brought on line at a rate of 2,000 BOPD with no indication of hydrogen sulfide. Vaalco (28.07%) is the operator with partners Addax Petroleum (31.63%), Sasol (27.75%), Asia Pacific KrisEnergy started drilling the Rossukon-2 exploration well on Block G6/48 in the Gulf of Thailand, using the Key Gibraltar jackup rig. The well will reach a total depth at 5,462 ft and will test Early Miocene stacked fluvial sandstones on a broad structural high. The well will also appraise the Rossukon-1 reservoir, which produced 850 BOPD during tests.
The Greater Tortue Ahmeyim (GTA) field offshore Mauritania and Senegal is a large, deep-water gas complex with two main reservoir sequences, the Lower Cenomanian and the Albian. The area was discovered by Kosmos Energy (Kosmos) in April 2015 by the Tortue-1 discovery well. Kosmos has since successfully confirmed three major fairways of the Senegal River Trend within the broader Mauritania and Senegal basin with the Guembeul-1A, Marsouin-1, Ahmeyim-2, Teranga-1, and Yakaar-1 wells. The outboard Cretaceous petroleum system offshore Mauritania and Senegal is potentially one of the largest petroleum systems ever opened along the Atlantic Margin.
Kosmos entered into a joint venture partnership with BP in respect of its interests in Mauritania and Senegal in December 2016. Dynamic production data was desired to further appraise the Lower Cenomanian reservoirs. A fast-track Drill Stem Test (DST) was conceived, planned, and conducted on the Tortue-1 discovery well beginning in June 2017 to assist in validating reservoir connectivity, productivity, original gas-in-place, and fluid quality. The DST, operated by Kosmos on behalf of the partnership, targeted two distinct reservoirs within the Lower Cenomanian sequence. The key information extracted from the well test has been used to support the Front End Engineering Design (FEED) currently underway, with a corresponding Final Investment Decision (FID) planned in late 2018.
This paper presents the objectives and design methodology, as well as the technical and operational challenges while conducting a dual-zone, high rate gas well test in ultra deep water within a compressed time schedule. This paper also presents the technology that Kosmos and BP selected to isolate the test intervals and gather pressure and temperature data during the extended flowing and buildup periods.
Finally, the key results of the DST are highlighted that underpin the development concept for the Tortue field.
The drilling strategy of North Kuwait has embraced in the last few years to get more reservoir contact to maximize oil recovery. Presently, the wells are drilled with high deviation angle to intersect multiple pay zones and drain the existing prospects. However, water coning and edge water breakthrough are challenging to achieve production longevity. Inflow Control Devices (ICD) is a proved tool in oil industry, which can delay the water encroachment by creating uniform drawdown across wellbore section. The production performance of ICD wells indicated stability of water cut for longer period as designed.
Answer products is the key to monitor downhole production profile to ensure the functionality of ICD units. Some reservoirs are suffering from pressure depletion and artificial lift (ESP) was installed to deepest point to increase pump efficiency. This type of completions is limiting accessibility to collect downhole data for further action.
Besides, after period if the water shutoff is required, the well intervention inside ICD completion is challenging due to bore size limitation and materials availability.
Proactive action was taken to utilize the advanced technology of ICD Completion, which allows faster execution of Rigless shutoff and reduce Rigs demands.
Copyright 2015, held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA) and the submitting authors. This paper was prepared for presentation at the SPWLA 56th Annual Logging Symposium held in Long Beach, California, USA, July 18-22, 2015. ABSTRACT Oil, gas, and condensate are produced in offshore Gabon where conventional formation evaluation techniques are often inadequate. Clay volume, water saturation, and reservoir quality are highly variable and unpredictable based on only conventional logs. Fluid type analysis is a key formation evaluation facet because reservoir compartmentalization is prevalent, resulting in unanticipated fluid column profiles, including free water on top of oil and oil on top of gas. Although NMR fluid type analysis enhances fluid column profiling, the method is affected by mud filtrate invasion because of limited NMR depth of investigation, which compromises the validity of the technique in some cases. A new formation evaluation approach evolved from NMR fluid typing whereby pressure testing and pump-out fluid sampling are used to confirm and normalize NMR predictions. In addition, pressure testing is used to determine formation pressure and mobility before initiating sampling operations. If mobility is high enough to move formation fluids, a pump-out operation is initiated to monitor the degree of filtrate contamination and to determine fluid type before initiating sample collection. This integrated workflow combines conventional log and NMR with pressure testing and fluid sampling analysis to confirm fluid type and reservoir quality interpretation. 1 Another key aspect of this integrated approach is the simulation of the pumping time required to reduce filtrate contamination to an acceptable level to determine fluid type and collect PVT-quality fluid samples.
As a result of a more aggressive exploration strategy, Total has recently entered many large blocks in new countries around the globe, often in frontier areas devoid of adapted seismic grid. Short contractual turnarounds, challenging environments, new play types, complex geology, cost containment, have lead to new exploration strategies and technological and organizational adaptations on the way geophysical surveys are designed, planned, processed and interpreted.In this paper, a couple of recent technologies are exemplified for surveys acquired or planned by Total in different environmental and geological settings.
These achievements to properly address new exploration challenges rely greatly on the technologies developed by geophysical contractors (new acquisition techniques and equipment, processing capabilities). However they have been made possible thanks to Total’s R&D realizations in developing proprietary softwares in seismic velocity model building, depth-imaging, modeling, and interpretation. Moreover, Total is one of the few E&P majors to have developed High Performance Computing1 (HPC) capabilities to serve its ambition as a leader in advanced and fast depth imaging.
Tamannai, Muhammad S. (_) | Hansen, Thomas (Petroleum Geo-Services) | Borsato, Ron (Petroleum Geo-Services) | Greenhalgh, Jennifer (Petroleum Geo-Services) | Moussavou, Martial-Rufin (Direction Générale des Hydrocarbures Gabon) | Essongue, Landry Olouchy (Direction Générale des Hydrocarbures Gabon)
Summary This study addresses the hydrocarbon prospectivity analysis of the offshore Gabon region comprising the North and South Gabon Basins based on interpretation of merged 3D seismic surveys and well data. Introduction Gabon is situated in the west coast of Africa (figure 1) bounded by Cameroon, Equatorial Guinea, Congo and the Atlantic Ocean. Oil and gas exploration in Gabon dates back to the 1920s with the first commercial discovery, the Ozouri field, which was made by Elf and brought onstream in 1956. Between then and the late 1990s a large number of oil and gas discoveries were made both onshore and offshore making Gabon Africa's eighth largest oil producer. Production has long been established from the pre-salt section onshore and in shallow water offshore but this has not yet been extended to the deeper water offshore.
Copyright 2012, Society of Petroleum Engineers This paper was prepared for presentation at the Abu Dhabi International Petroleum Exhibition & Conference held in Abu Dhabi, UAE, 11-14 November 2012. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited.