Asia Pacific Santos discovered gas with the Corvus-2 well in the Carnarvon Basin, offshore Western Australia. The well, located in permit WA-45-R, in which Santos has a 100% interest, reached a total depth of 3998 m. It intersected a gross interval of 638 m, one of the largest columns discovered across the North West Shelf. Wireline logging to date has confirmed 245 m of net hydrocarbon pay across the target reservoirs. Total SA and partners ExxonMobil and Oil Search have signed a gas agreement with the government of Papua New Guinea that defines the fiscal framework for the Papua LNG project in the country's Eastern Highlands. The plan involves construction of three 2.7-mtpa LNG trains on the existing PNG-LNG plant site at Caution Bay just west of Port Moresby. Total has 31.1% interest, ExxonMobil has 28.3% interest, and Oil Search has 17.7%.
Africa (Sub-Sahara) A drillstem test was performed on the Zafarani-2 well--located about 80 km offshore southern Tanzania. Two separate intervals were tested, and the well flowed at a maximum of 66 MMscf/D of gas. Statoil (65%) is the operator, on behalf of Tanzania Petroleum Development Corporation, with partner ExxonMobil Exploration and Production Tanzania (35%). The FA-1 well--located in 600 m of water in the Foum Assaka license area offshore Morocco--was spudded. The well targets Eagle prospect Lower Cretaceous resources. Target depth is 4000 m. Kosmos Energy (29.9%) is the operator, with partners BP (26.4%),
Africa (Sub-Sahara) BG Group discovered gas in the Taachui-1 well and sidetrack in Block 1, offshore Tanzania. The drillship Deepsea Metro Idrilled Taachui-1 close to the western boundary of Block 1, then sidetracked the well and drilled to a total depth of 4215 m. The well encountered gas in a single gross column of 289 m within the targeted Cretaceous reservoir interval. Net pay totaled 155 m. Estimates of the mean recoverable gas resources are around 1 Tcf. Statoil (65%) and co-venturer ExxonMobil (35%) made a sixth discovery--the Piri-1 well--in Block 2 offshore Tanzania. Piri-1 was drilled by drillship Discoverer Americas, at a water depth of 2360 m.
Africa (Sub-Sahara) The drillship Ocean Rig Athena is preparing to drill appraisal and exploration wells offshore Senegal for a joint venture (JV) led by Cairn Energy. Two wells will appraise the SNE discovery, which was ranked by IHS CERA as the world's largest for oil last year. An exploration well will also be drilled in the Bellatrix prospect, for which mapping has indicated a potential 168 million bbl of oil resources. Cairn holds a 40% interest in the JV, with remaining interests held by ConocoPhillips (35%), FAR (15%), and Petrosen (10%). The Ksiri West-A exploration well drilled by Circle Oil on the Sebou permit onshore Morocco has flowed gas at a rate of 8 MMcf/D following tests. It is being readied for production.
Flotron, Alyssa (Kansas Interdisciplinary Carbonates Consortium [KICC], University of Kansas) | Franseen, Evan (Kansas Interdisciplinary Carbonates Consortium [KICC], University of Kansas) | Goldstein, Robert (Kansas Interdisciplinary Carbonates Consortium [KICC], University of Kansas)
Controls on deposition and reservoir quality of mixed unconventional carbonates and siliciclastics are not adequately understood. This project explores the Wolfcamp ‘A’ (early Leonardian) in Howard County, TX to determine what stratigraphic and sedimentologic controls lead to areas with the best reservoirs.
Core, thin section, XRD, TRA, and rock-eval pyrolysis data were used to analyze sedimentary facies and rock properties. Core observations were used to calibrate facies to 1122 well logs, which were used to correlate the Wolfcamp A internal stratigraphy across an area of 3637 km2. Facies distribution and thickness were mapped in each stratigraphic package to analyze controls on distribution of high and low reservoir-quality sediment gravity flow (SGF) facies.
Out of 11 lithofacies, the dominant facies assemblages are coarse-grained packstone-floatstone-rudstone (CGC), fine-grained calcareous mudstone-wackestone (FGMW), and siliceous mudstone-siltstone (SMS). CGC facies have sharp, locally erosive surfaces, rip-up clasts, are massive or have internal grading, suggesting deposition from SGFs. The dominance of detrital quartz, lack of radiolarians, rarity of shallow-water skeletal fragments, and massive or normal graded laminations suggest SMS and FGMW were deposited as SGFs with a separate siliciclastic (SMS) or carbonate slope (FGMW) source. SMS facies have the best unconventional reservoir potential, with total porosity ranging from ~6-10%, TOC of 2-3.2 wt%, and low clay content (<50%).
Six regionally identifiable major units show progradational and compensational geometries, and each pair of major units has wedge-on-wedge relationships. The lowest two major units are CGC-rich, the middle two are characterized by SMS facies, and the upper two contain all three facies assemblages. The three major units that are thickest proximally are lobe-shaped and sourced from between the Eastern Shelf and Glasscock “nose” with internal units downlapping basinwards. The other three major units are thickest distally and laterally with internal units onlapping proximally and, with some exceptions, are mostly sourced from the Eastern Shelf and Glasscock “nose.”
The results suggest CGC facies were commonly deposited during high relative sea level whereas most SMS and FGMW facies were deposited during low relative sea level. Notch-like features in the slope acted as foci for SGFs. Promising sweet spots of greatest thickness and SMS prevalence are in the middle pair of major units and located near a northeast-southwest trend of thick SMS deposition situated medially. The distribution of those sweet spots is predictable by mapping paleotopographic funneling mechanisms, and understanding how relative sea level controls facies distribution and how paleotopography controls sediment dispersal and geometries. These controls are broadly applicable across areas of the Permian Basin.
Africa (Sub-Sahara) Sound Energy identified significant gas shows at the first Tendrara well onshore Morocco. Drilled to a 2665-m measured vertical depth, the well hit a total gross pay interval of 89 m of gas. The full set of well logs are being processed before the startup of rigless mechanical reservoir stimulation operations, which will be followed by a well test. The company is the operator of the well with a 55% working interest.
Africa (Sub-Sahara) Shell has initiated a two-well drilling program in blocks 1 and 4 of the Mafia Deep basin offshore Tanzania. Drilling is taking place in water depths of up to 7,545 ft, with the company and its joint-venture partners Pavilion Energy and Ophir Energy investing almost USD 80 million in the program. The two wells will meet the remaining requirements in the exploration licenses issued by the Tanzanian Ministry of Energy and Minerals. Asia Pacific Petronas has begun gas production from the world's first floating liquefied natural gas (FLNG) facility, the PFLNG SATU, at the Kanowit field offshore Malaysia's Sarawak state. The first-gas milestone marked the onset of commissioning and startup for the FLNG facility, preceding commercial production and initial cargo shipment. The facility is fitted with an external turret for operating in water depths of 229 ft to 656 ft. It will extract gas through a flexible subsea pipeline for the liquefaction, production, storage, and offloading of LNG at the field.
Africa (Sub-Sahara) Eni has begun production from the Vandumbu field and made a new oil discovery in the Afoxé exploration prospect in Block 15/06 offshore Angola. First oil from the Vandumbu field, through the N'Goma floating production, storage, and offloading vessel, was achieved in late November, 3 months ahead of schedule. Vandumbu is approximately 350 km northwest of Luanda and 130 km west of Soyo. This, along with the startup of a subsea multiphase boosting system in early December, boosts oil production from Block 15/06 by 20,000 B/D. The rampup of Vandumbu is expected to be completed in 1Q 2019. Block 15/06 is being developed by a joint venture formed by Eni (36.84%, operator), Sonangol (36.84%), and SSI Fifteen (26.32%). Asia Pacific Ophir Energy's Paus Biru-1 exploration well in the Sampang production-sharing contract (PSC) offshore Indonesia has resulted in a gas discovery.
P. O., Avbenake (Chemical and Petroleum Engineering Department, Bayero University) | B. Y., Jibril (Chemical Engineering Department Ahmadu Bello University) | R. S., Al-Hajri (Petroleum and Chemical Engineering Department, Sultan Qaboos University)
NiCo/γ-Al2O3 catalyst was prepared and used to upgrade heavy crude oil in a batch reactor at 380°C and 32 bar Hydrogen or Nitrogen gas for 2 hours. The effect of water-gas shift reaction on the upgrading process was studied by utilizing the water-in-oil for non-dehydrated crude with 20.77 wt% water content. To study this, two distinct experiments were performed; the first was in Hydrogen media with catalysts and water-gas shift reaction was excluded from partaking using an inner liner in the reactor. Subsequently, a second reaction in Nitrogen environment and catalysts with water-gas shift reaction was performed to measure the effect of this type of aquathermolysis reaction. The results show that the latter experienced 96.71% viscosity reduction as against 90.68% with the former. GC-MS and FT-IR analysis confirms that water-gas shift reaction promotes a type of hydrogenation reaction resulting in higher saturates contents of the upgraded oil as compared to using pure hydrogen gas. In a bid to buttress the importance of catalysts, thermal cracking was performed in both Hydrogen and Nitrogen media and GC-FID results show that the quantities of marketable components in the crude oil were higher with catalytic upgrading than thermal cracking. XRD was subsequently used to ascertain the crystalline structure of the catalysts.
Acquisition of fluid samples using wireline-formation testers (WFTs) is an integral part of reservoir evaluation and fluid characterization. Recent developments in formation-tester hardware have enabled wireline-based fluid sampling in a wide range of downhole conditions. However, accurate quantification of oil-based-mud (OBM) filtrate contamination using data from downhole-fluid-analysis (DFA) sensors alone remains challenging, especially in difficult sampling environments and for advanced sampling tools that have complex inflow geometries and active guarding of filtrate flows. Such tools and conditions lead to contamination behaviors that do not follow simple power-law models that are commonly assumed in OBM-contamination-monitoring (OCM) algorithms.
In this paper, we introduce a new OCM algorithm derived from an inversion of DFA data using a full 3D numerical flow model of the contamination-cleanup process. Using formation and fluid properties and operational tool settings, the model predicts the evolution of filtrate contamination as a function of time and pumped volume, and can thus be used to forward model the DFA sensor responses. Sensor data are then inverted in real time to provide contamination predictions. Real-time computation is enabled through fast, high-fidelity proxy models for the cleanup process. The proxy models are trained on and thoroughly vetted against a large number of full-scale numerical simulations. Compared with existing algorithms, the new OCM method is now applicable for all types of sampling hardware and a wider set of operating conditions. By directly relying on a model of the cleanup process, the physical properties of the formation and fluids (such as porosity, permeability, viscosity, and depth of filtrate invasion) are estimated during the inversion, thus providing additional valuable information for formation evaluation.
The new method is demonstrated by practical application in both synthetic and field examples of oil sampling in OBM. The synthetic examples demonstrate the robustness of the algorithm and show that the true formation and fluid properties can be recovered from noise-corrupted sensor data. The field example presented demonstrates that contamination predictions are in good agreement with results from laboratory analysis, and the inverted formation properties are consistent with estimates derived from openhole logs and pressure measurements.