The Shushufindi field, located in the Oriente basin of Ecuador, has been producing since 1972. In December 2011, the field had approximately 150 wells, with a total production of 45,000 bopd. Field operations were then passed to the Consorcio Shushufindi (CSSFD) led by Schlumberger for a period of 15 years. Since then, 30 new wells and 26 workovers have been completed by Schlumberger Production Management (SPM) in the field, with a production of 60,000 bopd in May 2013.A methodology with four successive distinct phases was created, aiming for a complete reservoir characterization over 18 months prior to delivering the five-year field development plan (FDP) in October 2013. Each petrophysical phase focused on providing a reliable basis for the first two years of operations, and regular updates to the static and dynamic models.In conjunction with operations support, a comprehensive data acquisition plan was launched with advanced core analysis and special logs to support the advanced reservoir characterization. The deployment of technologies such as the Dielectric Scanner* multifrequency dielectric dispersion service, the combinable magnetic resonance tool, and the FMI* fullbore formation microimager, among others, was key in revealing the reservoir's true characteristics.Advanced petrophysics delivered a description of the main reservoir heterogeneities and properties, along with a facies characterization tied to an advanced core analysis including capillary pressure and pore throat size measurements. From this, hydraulic flow units were established in a deterministic characterization over the waterflood pilot well patterns. Additionally, a quantitative evaluation of thin beds and low resistivity pay zones provides the potential for their incorporation in the original oilin-place computation. These findings have contributed to a revision of the depositional concepts for the field.
The Oriente Basin is located in eastern Ecuador at the Amazon rainforest. Shushufindi-Aguarico field is one of the most important fields in Oriente Basin with over 12% of the national production; the main hydrocarbon reservoirs are located inside the Cretaceous formations Napo and Tena. In spite of being a mature field in production since the beginning of 1970s, Shushufindi-Aguarico field still presents various formation evaluation challenges that can potentially be explored to enhance its productivity. In order to improve fluids characterization in a recently developed area at NorthWest of the field, a new reservoir evaluation technology, Fluid Logging and Analysis in Real Time, is introduced to obtain a continuous log of quantitative composition of hydrocarbon and an improving in the pay zones analysis from gas presence in the mud while drilling. The prospective intervals determination within the productive reservoirs is performed while drilling with cuttings analysis and chromatography evaluation in real time. This evaluation is based on Gas Ratio Method, which uses the relation between heavy, medium and light gases to identify porous rocks with hydrocarbon presence. The prospective intervals determination using Advanced Surface Fluid Logging technology gives more precision to identify thin beds by eliminating the recycled gas effect than conventional mud logging. In addition, the Advanced Surface Fluid Logging provides fluid composition in the C1-C5 range analogous to the PVT single phase composition. The fluid composition achieved in the main target zone exhibited a close correlation with a convention PVT from a recent offset well. This paper presents a case study where ASFL technology was tested on a Shushufindi well highlighting valuable benefits, with better pay zones definition in the challenging geological environments encountered in the Shushufindi-Aguarico field. The reliability of the data provided is demonstrated by the good correlation amongst the Fluid Logging and Analysis in Real Time composition recorded in the main target zone and a recent PVT composition from a nearby offset well.
The Eden Yuturi field, first exploited in 2002, is located in the northeast of the Oriente basin, Ecuador. The field was initially operated by Occidental Petroleum and has been operated by Petroamazonas EP (PAM) since 2006. From its peak production of 83.8 million B/D in August 2004, the field declined and now produces less than 30 million B/D, with a water cut of 92%. In 2014, PAM awarded an incremental production based service contract to the Kamana Services consortium, with the objective of reversing the field decline and increasing the recovery factor by optimizing production and applying enhanced oil recovery techniques.The Lower U in the Cretaceous Napo formation is one of the most important reservoirs in this mature field and has a cumulative oil production of 48.1 million barrels (as of July 2015) from 110 wells. The production is supported by a water drive mechanism and a strong aquifer.The major challenge for the consortium is to define an optimal field development plan that maximizes the current recovery factor of 34%. To achieve this goal, it is crucial to enhance the reservoir characterization by integrating all the available information from multiple disciplines and use this knowledge to understand the fluid dynamics in the reservoir.The sedimentary column of the Lower U is interpreted as fluvial at the base follow by tide-dominated estuarine tidal shelf deposits grading into lower shoreface deposits towards the top of the reservoir. This transition subdivides the reservoir column into different hydraulic units. However, the vertical stacking of these hydraulic units is not present across the whole field, and amalgamation has been observed in specific zones. The fluid dynamics changes inside the reservoir have a large impact on the waterdrive mechanism sweep efficiency, as identified in the pressure and production performance analysis of the reservoir across the area, and differences in pressure levels and water cuts trends are evident.Therefore, a proper stratigraphic characterization is the key to optimizing the field development strategy of the Lower U reservoir to improve the ultimate recovery factor.In this paper, we describe how the stratigraphic characterization has been performed and the final framework obtained by the multidisciplinary team, to be used for the optimized development strategy of the Lower U reservoir.
Over the years, simulation models have been helping oil companies and stakeholders to make investment decisions. However, these models are not always available to help with the field development planning. A fast and efficient workflow performed for the identification of new opportunities in the Pañacocha field is presented. To start the workflow, a conceptual geological model was identified for each reservoir, based on the available data and nearby analog fields. Quality control, updating and reinterpretation of well top data, petrophysical parameters maps (net pay, porosity, and water saturation), and original oil in place estimations were carried out to identify untouched areas. A total of 45 locations that may still contain oil were identified. For the next step, a decline curve analysis was carried out, and well type curves were generated to determine the estimated ultimate reserves (EUR), drainage area, and recovery factor by well. The range of recoverable oil associated with each location was estimated by varying all the parameters involved in the volumetric formula. Finally, the locations were ranked based on their production potential. The selection of drilling targets included the associated geological and operational risk. A base case, based on the contract minimum commitments, is presented. However, this study shows that a more aggressive drilling campaign is possible. In conclusion, this workflow allowed us to have a better understanding of the field potential. Oil in place volumes and recovery factors were updated. Analysis of produced fluids helped to assess reservoir performance. The economic analysis following this study will help in selecting the best option to develop the field.
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.