Africa (Sub-Sahara) Algeria awarded four of 31 oil and gas field blocks on offer to foreign consortiums in its first auction since 2011. Shell and Repsol won permits for the Boughezoul area in the north of the country, while Shell and Statoil won permits for the Timissit area in the east. A consortium of Enel and Dragon Oil was awarded permits for both the Tinrhert and the Msari Akabli areas. Circle Oil's CGD-12 well, located onshore Morocco in the Sebou permit, encountered natural gas at different levels within the Guebbas and Hoot sands. Wireline logging analysis confirmed a net 9.7 m of pay. The first test, over the Intra Hoot sands, flowed gas at a sustained rate of 2.21 MMscf/D through an 18/64‑in. The primary target, the Main Hoot sands, flowed at a sustained rate of 4.62 MMscf/D through a 24/64-in.
Africa (Sub-Sahara) Eni Congo discovered oil at its Minsala Marine 1 well offshore the Republic of the Congo in Marine XII Block 12 km from the operator's recent Nené Marine discovery. Minsala intersected 420 m of gross pay and encountered light oil in a Lower Cretaceous presalt sequence. The well reached a total depth of 3700 m. Eni (65%) is operator, with state-owned partner SNPC 25%), and New Age (African Global Energy) Limited (10%). SOCO EPC's Lindongo X Marine 101 Well (LXM-101)--located offshore the Republic of Congo in Marine XI Block--encountered oil in a clastic sequence of the Djeno sands, with early log interpretation indicating approximately 50 m of gross pay.
Africa (Sub-Sahara) Eni started production from the Nené Marine field, which sits in the Marine XII block in 28 m of water, 17 km offshore the Republic of the Congo. The first phase of the field produces from the Djeno pre-salt formation, 2.5 km below the ocean floor at a rate of 7,500 BOEPD. Future development will take place in several stages and will involve the installation of more production platforms and the drilling of at least 30 wells. Eni (65%) is the operator with partners New Age (25%), and Société Nationale des Pétroles du Congo (10%). The well's primary target is the Bunian structure: a four-way, fault-bounded anticline, which was defined by a 3D seismic survey. It will be drilled to a total depth of 1682 m.
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.
This course will discuss the practical state-of-the-art techniques of Volume to Value (VV) to help attendees assess exploratory deepwater offshore oil and gas prospects and quantify economic values of the prospects. Attendees will learn how to develop a preliminary field development plan for a given discovery prospect and estimate oil and gas recovery, wells required, and costs. They will also learn how to conduct economic evaluation for lease sales or farm-in opportunities. Upon completion of this course, attendees should be able to evaluate the commercial potential of original oil and gas in-place in exploratory blocks and develop preliminary field development plans. Attendees should also be able to obtain value of the opportunity in order to make the decision to go ahead and develop the field or walk away from it, as well as identify constraints in terms of geology and engineering that will make it viable or impede the realization of the project.
Cornelius, Sharon (Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas) | Castagna, John P. (Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas) | Emmet, Peter A. (Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas)
Composite medium modeling of mixed salt-body mineralogies and multiple regression analysis lead to the conclusion that this velocity variation can be explained by the lithological variation within the salt, which also varies by latitude.
Brazil’s state-owned Petrobras and El Dorado, Arkansas-based Murphy Oil have agreed to combine most of their US Gulf of Mexico assets to form a joint venture (JV) that will average 75,000 BOE/D in production during the fourth quarter. Murphy Exploration & Production will serve as the JV’s operator with an 80% stake, while Petrobras America will hold 20%. The deal excludes exploration blocks from both companies, with the exception of Petrobras’ blocks that hold deep exploration rights. As part of the deal, Petrobras could receive more than $1 billion, including $900 million in cash and $150 million if price and production benchmarks are surpassed during 2019–2025. Murphy will also cover $50 million of Petrobras' costs at the Chevron-operated St. Malo Field if enhanced oil recovery projects are greenlit.
Li, Hongyan (Schlumberger) | Zhang, Lu Xin (Schlumberger) | Weir, Brian (Schlumberger) | Hutson, Jarrod (Schlumberger) | Ramirez-Cuellar, Arturo (WesternGeco) | Chen, Suyang (WesternGeco) | Koechner, Betty (WesternGeco) | Gardner, Jason (WesternGeco)
Building an accurate supra-salt sediment velocity model is critical for salt interpretation, subsalt imaging and image-to-well tie. By combining well data and multiple-azimuth seismic data in a joint inversion, tilted transverse isotropy tomography is able to invert for Vp, epsilon, and delta simultaneously, improving gather flatness and well marker tie at the same time. However, reflection tomography is less effective in shale body areas where a lack of reflectivity is one of the main culprits. It also has some difficulty in areas where carbonate rafts are present, which have much higher velocity than surrounding sediments. Full-waveform inversion is able to use refracted waves and diving waves other than reflections; therefore, it can complement reflection tomography in the challenging areas where reflection tomography has difficulties to resolve. The combined work flow was successfully implemented on a large project in the central US Gulf of Mexico where the water depth varies from few hundred feet to several thousand feet, with the known presence of massive shale bodies and carbonate rafts.
Presentation Date: Tuesday, October 18, 2016
Start Time: 1:00:00 PM
Presentation Type: ORAL
Subsalt velocity model building is challenging due to a limited seismic raypath, narrow angle coverage, scattering effects, and mode conversion caused by the large elastic property contrast between the salt body and background sediments. Uncertainty in the salt geometry and lack of well control aggregate further the subsalt velocity model-building process.
To overcome these drawbacks, a workflow that integrates well and seismic data, guided by a regional stratigraphic framework, and constrained by rock-physics modeling was adopted to generate a basin-scale subsalt velocity model that covers more than 50,000 km2 (over 2,000 Outer Continental Shelf (OCS) blocks) in the central Gulf of Mexico. Over 300 subsalt wells and multiple wide-azimuth and full-azimuth seismic surveys were utilized to build the model. The velocity model was further validated through iterations of full-azimuth subsalt tomography. As a result, the final velocity model is consistent with both well and seismic measurements, follows stratigraphic framework, and obeys the law of rock physics. The final model was used in prestack depth migration of wide-azimuth and full-azimuth seismic data over the entire area, yielding a superb result. It can be used as a benchmark earth velocity model in the central Gulf of Mexico for exploration and appraisal applications.
Presentation Date: Wednesday, October 19, 2016
Start Time: 3:10:00 PM
Presentation Type: ORAL