ABSTRACT
A casing leak repair alternative is presented to allow continued hydraulic fracture treatment of an unconventional formation. Analysis of diagnostic operations, selection of the best alternative, and the results are detailed. This paper details the diagnostic operations (annular circulation test, multifinger caliper log, leak chase with hydraulic packer on Coiled Tubing, fluid transit evaluation, and real-time camera downhole images acquisition) to identify the casing leak zone and the analyzed repair alternatives with the final selection of a casing patch. To verify the pipe body shield strength and burst pressure post-patch expansion, a finite element analysis in dynamic condition was carried out to limit the hydraulic fracture pumping parameters. This paper covers details on repair operations executed, verification analysis to confirm original frac treatment continuity, and lower & upper completion installation. The diagnostics operations allowed pinpointing casing leak detection and selection of possible repair alternatives. The repair was carried out as planned involving many services companies. A solution was implemented with local staff and services considering the COVID context with travel restrictions of the patch owners. Web broadcasting CT surface parameters allowed real-time support from casing patch suppliers during the entire intervention. The completion plan with 24 frac stages performed through the casing patch was successfully executed. The production packer with an OD of 99.5% of the casing patch drift was run through the casing patch and wireline set without any problem. Considering well integrity conditions throughout the entire well production life as the main intervention objective, this paper introduces a successful alternative to repair casing failures on an unconventional well that allowed hydraulic fractures continuity to accomplish the original frac plan. The well production was higher than the Estimated Ultimate Recovery (EUR) expected for the landing zone. Copyright 2023, Society of Petroleum Engineers.
ABSTRACT
Reservoir surveillance and production optimization will remain at the forefront of company strategies in the new post-COVID19 environment. We anticipate that companies will focus more on producing assets and go the route of production enhancement rather than exploration. Accordingly, production logging will remain an important surveillance method in evaluating and strategizing production-optimization schemes pertaining to flow-characterization from reservoir-to-wellbore. This work is culmination of operational and technical excellence that enabled the revival of a loaded-up well through simultaneous lifting-and-logging technique. Conventionally, wireline is the preferred mode of conveyance for production-logging;however, well must be continuously flowing throughout acquisition timeframe. Kicking-off the well using nitrogen-lift and then bringing in wireline-unit for production-logging in Well A-4 was not feasible as previous attempts confirmed well to load-up in few hours post-offloading. Therefore, success of this project was heavily dependent on initial planning stage, which accounted for all available data including production-history, well-events, intervention-details, fluid analysis and well load-up behavior. Next, a multi-domain approach was adopted while bringing-out each domain from its silos and strategize collectively to simultaneously kickoff the well with nitrogen and acquire real-time downhole production-logging data through smart-coiled-tubing (CT). This was first implementation of concurrent lifting and logging operation in Pakistan. By deploying the approach mentioned above through smart CT (using optical-telemetry-link inside the CT-string coupled with downhole-assembly), synchronized lifting-and-logging operation was carried-out successfully. Well was observed to swiftly go back to load-up conditions post-kickoff;however, continuous well dynamics monitoring downhole enabled us to log perforated interval across multiple time domains. Well was activated through CT nitrogen-injection but depicted continuous loading tendency, which was captured downhole in form of flow-transients. Real-time job optimization ensured vigilant monitoring and selection of right-time to acquire meaningful zonal-contribution data for evaluation and diagnostic solutions. Finally, operational excellence was complemented through technical data analysis and interpretation, integrating passes data with transients and stationary measurements. Ultimately, acquired data analyzed using an integrated lens involving fluid velocities, downhole density, temperature, and water hold up data. Consequently, enabling us to decipher gas and water-entries on a zonal-basis across perforated sandstone reservoir. Copyright © 2022, Society of Petroleum Engineers.
ABSTRACT
Eastern Indonesia, including the island of Halmahera, is a region with a high mineral potential, particularly Ni-Co, Au-Cu, and Ag ores, which are a globally important and critical source of raw materials (CRMs). The research was conducted within the framework of scientific cooperation between the Faculty of Geology, University of Warsaw (Poland), and PT Halmahera Resources Percasa Ltd. (Jakarta, Indonesia) Between the years of 2009 and 2011, 42 boreholes were drilled using an impact system (up to 15 m below surface) and 3 test pits (up to 8 m below surface). The presence of a laterite deposit containing Ni-Co mineralization was identified on the license area. The resources estimated in accordance with JORC Code, with a cut-off grade Ni ≥ 0.5%, equaling 185,510 t Ni and 17,747 t Co, with the stock of raw material amounting to 14.8 million t and with an average content of 1.00% Ni and 0.13% Co. The ore in the deposit has mixed character. To date, studies have shown the dominance of oxide ore, but saprolite composed of magnesium silicates was also identified in significant amount. The Ni mineralization in oxide ore (limonite) is bound to goethite and manganese minerals, while in the case of silicate (saprolite) ore, it occurs locally in the form of veins as well as zonally in the weathered serpentinites. Cobalt mineralization is almost entirely related to the Mn minerals that occur in the lower oxide zone. It has been found that both serpentinites and harzburgites (and possibly locally lherzolite) are the parent rocks for laterite deposit.
ABSTRACT
Recent years and especially the coronavirus pandemic have been very challenging for the oil industry, resulting in a significant reduction in investment, forcing companies to review budgets and search for more efficient and economical technologies to achieve the target level of hydrocarbon production and revenue generation. In PDO, one of the most challenging fields is "AS", where extreme downhole conditions require a very well-engineered approach to become economical. This field has already seen some of the most advanced technology trials in PDO that are also covered in multiple SPE papers. Based on the new approaches and techniques that were successfully implemented on recently drilled wells, it was decided to review the older, previously fractured wells in the area and assess them for a refracturing opportunity. The main challenge in this project was that these older wells were previously hydraulically fractured in multiple target intervals, therefore both zonal isolation and successful placement of the new fracs were becoming the major concerns. As the planned coverage by the new fractures was to ensure no bypassed pay, the only applicable technology on the market was a pinpoint fracturing process, whereby the targeted placement is achieved through limited entry perforations and focused energy of the injected fluid. The subject pinpoint technology anticipates that the limited entry sandblasting perforation is created and then proppant laden fluid is pumped through a sandblasting nozzle which is part of either a coiled tubing (CT) or a jointed pipe (JP) Bottom Hole Assembly (BHA), and the backside (or the annulus of the injection path) is used to maintain the positive backpressure from the top. This technology allows for choosing a desirable order of target interval selection inside the well, unlike conventional plug and perf or a simplified multistage completion, where the treatments must be placed only in order from bottom to top. Another advantage of this approach is a faster frac cycle through the elimination of wellbore cleanout requirement. Being a unique and first-ever application in the Middle East, using CT for placing frac treatments through a jetting nozzle demonstrates the full scale potential of this approach not only in conventional wells but also in complex, sour and High Pressure (HP) environments that are often found in the Sultanate of Oman and in the Middle East. This paper will cover the advantages and disadvantages, complexity and requirements, opportunities and lessons learnt in relation to this approach. © 2022, Society of Petroleum Engineers
ABSTRACT
The Alpine Field, located on the Coville River Delta on the North Slope of Alaska, has been developed exclusively with horizontal wells since 2000. Despite extensive knowledge accumulated throughout the development of the field, many geological uncertainties remain, due to the sedimentary and tectonic complexity of the field. The further development of the field included the drilling of a dual-lateral well targeting two sand layers at different stratigraphic positions within two siliciclastic depositional sequences separated by a major erosional surface stratigraphy of the target interval consists of divided by a major unconformity. Operations were further complicated by logistic consequences of the spreading of the Covid-19 pandemic, deeply affecting travel and physical interactions. These new work conditions would present a challenge to most operators on how to ensure fluid and timely communications between the geosteering team members working from different locations. Despite geological complexity, and the need for fully remote support, geosteering operations proved successful and achieved the desired planned objectives with 70% of the wellbore drilled within the target layer in the upper leg and 95% of the wellbore placed in the target layer in the lower leg. © 3rd EAGE/SPE Geosteering Workshop 2021.