This paper discusses the successful, fully integrated, three-dimensional (3D) earth modeling (EM) and dynamic reservoir simulation of the Hollin formation in the Lago Agrio field within an operator's first producer field in Ecuador. Early feedback of reservoir heterogeneity helped to understand key reservoir issues and methods undertaken to solve various problems. The implementation of cutting edge reservoir modeling techniques contributed to improving production rates and enhancing recovery. Improved understanding of the sedimentological model, diagenetic events, and capillary pressure analysis helped to identify eight rock types (RTs), which were then adequately propagated into a 3D geocellular model. This geocellular model overcomes a previous paradigm that reservoir heterogeneities and effectiveness upon convergence and nonmatching of dynamic reservoir simulation must be honored. Instead, a balanced result was achieved by making insightful changes in terms of upscaling the population model by replicating production history. This allowed pinpointing barriers, coning, and preferential aquifers layering to control bypassed oil, thereby helping to identify potential zones corroborated with new wells. Inexorable production decline in mature fields requires solutions to improve production rates and enhance recovery factors using reservoir modeling techniques. Typical characterization involves integration of EM and production performance to estimate reserves and develop optimal production. However, for mature fields, this process can be challenging when accelerated field development impacts fluid distribution and bypassed reserves. Early feedback of reservoir heterogeneity was used to understand key reservoir issues. Integration of sedimentological and petrophysical studies with reservoir simulation yielded information regarding complexities affecting rock quality, barriers, and baffles controlling water influx. Limited 3D seismic field coverage hindered reliable seismic interpretation because of the merging of two-dimensional (2D) lines and 3D seismic volume to populate a 3D structural grid. Gathering core porosity measurements using different methods with unappropriated net mean stress required homologate data for consistent overburden confining pressure using compressibility rock test relationships for rock typing. Finally, the innovative idea of modeling the fluvial, tidal, and shallow marine domains of the Hollin formation separately, which are in hydraulic connectivity with an infinite aquifer, allowed successful dynamic performance, accurately mimicking reservoir productivity and allowing water breakthrough prediction. This new approach provided robust analysis for a strong reservoir model, helping optimize the drilling development plan. Successful, fully integrated 3D EM and dynamic reservoir simulation of an operator's first producer field in Ecuador are discussed in this paper. This improved understanding of key reservoir issues and methods for solving various problems enables engineering solutions for improving production rates and enhancing recovery factors through the implementation of cutting edge reservoir modeling techniques.

The depositional environment at Statoil's Leismer SAGD demonstration project is dominated by a fluvial-deltaic system with complex geological features which present challenges for SAGD operations. An efficient monitoring tool that could combine geoscience data with production knowledge is vital for optimizing SAGD operational strategies. Time lapse (4D) seismic survey is one such monitoring tool. It can be integrated with wells and production data to prepare and optimize operational strategies. The pattern of growth of steam chamber is critical for well performance optimization. Steam chamber development dictates which reservoir areas are using heat efficiently and contributing to drainage of bitumen and increased production. At Leismer, two 4D monitor seismic surveys have been conducted since the start of operations. The 1st monitor was acquired in 2012 to observe one year of SAGD performance and the 2nd monitor in 2013 to observe the performance after 2 years of operation. These surveys have been used to identify challenges to maximizing well pair productivity. Of primary concern is the effective distribution of steam along the entire horizontal section of the SAGD well pair. Other 4D monitoring benefits include, monitoring subcools with respect to reservoir heterogeneities, bottom water communication, steam chamber coalescence, baffle or barrier to steam chamber growth identification. In this study, examples are presented to show how combining production and 4D seismic data has contributed to well pair optimization. Communication with bottom water in the early stages of SAGD, while rare, occurred in specific Leismer well pairs – analyses of production data combined with 4D seismic data helped identify steam loss into bottom water which drove steam injection strategy and improved well productivity. Another Leismer example shows how 4D seismic has been used to confirm a low reservoir roof at the toe of a particular well pair. This knowledge drove a change in injector well completion to optimize production. In the final example, it is shown how 4D seismic has helped analyze and confirm well conformance (heat distribution along SAGD well pairs) which is critical for uniform steam chamber development. Based on Statoil's Leismer experience of applying results of 4D seismic analyses for well optimization, it can be concluded that 4D seismic has proven to be a very useful and value adding monitoring tool.

Summary 4D seismic is one of the main sources of dynamic data for heavy-oil-reservoir monitoring and management. 4D seismic is significant because seismic attributes such as velocity and impedance depend on variations in reservoir-fluid content, temperature, and pressure distribution as a result of hydrocarbon production. Thus, the large-scale nature of fluid flow within the reservoir can be evaluated through information provided by 4D-seismic data. Such information may be described as anomalies in fluid flow that can be inferred from the unusual patterns in variations of a seismic attribute. During steam-assisted gravity drainage (SAGD), the steam-chamber propagation is fairly clear from 4D-seismic data mainly because of changes in reservoir conditions caused by steam injection and bitumen production. Anomalies in the propagation of the steam chamber reflect the quality of fluid flow within the reservoir. A practical methodology is implemented for integration of 4D seismic into SAGD reservoir characterization for the Surmont project.

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This paper provides documentation of six cases in which Thermally Stable Diamond (TSD) bits were used in combination with downhole motors yielding economically successful results in the Permian Basin. In addition, a detailed discussion of the TSD cutting element and TSD bit design is presented. This discussion compares the TSD to natural diamonds and polycrystalline diamond compacts (PDC's) and explains why TSD bits are superior in some applications.