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Petroleum Engineering, University of Houston, 2. Metarock Laboratories, 3. Department of Earth and Atmospheric Sciences, University of Houston) 16:00-16:30 Break and Walk to Bizzell Museum 16:30-17:30 Tour: History of Science Collections, Bizzell Memorial Library, The University of Oklahoma 17:30-19:00 Networking Reception: Thurman J. White Forum Building
- Research Report > New Finding (0.93)
- Overview (0.68)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Mineral (0.72)
- Geology > Rock Type > Sedimentary Rock > Carbonate Rock (0.68)
- (2 more...)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling (0.93)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- (20 more...)
- North America > United States > Texas (1.00)
- Europe (0.93)
- Research Report > New Finding (0.93)
- Overview (0.88)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Carbonate Rock (0.68)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Sandstone (0.47)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling (0.93)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale gas (1.00)
- Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
- (20 more...)
Abstract One of the challenges encountered in hydraulic fracturing of unconventional resources is casing deformation. Casing deformation statistics vary across different regions of the world, but it is estimated to affect 20-30% of horizontal wells in some areas of operations. The consequences of casing failures can be varied but, in many cases, it affects the well production, wellbore accessibility and in some rare instances presents a situation of well control and its associated risks. Incidentally, most literature on casing deformation pertains to "plug & perf" fracturing operations in cemented completions though pipe deformation is known to occur in multi-stage fracturing (MSF) sleeves type of openhole completions as well. Intuitively, the two failure mechanisms may appear similar instead they represent very diverse well conditions that lead to pipe deformation. Tubular damage during fracturing is not caused by a single, consistent reason. Multiple mechanisms may be responsible for casing deformation; formation rock properties, wellbore configuration, cyclic loads acting on the tubulars, tubular quality, cement bond, or simply some operational aspects during drilling and completion conducive to pipe deformation. Tubing stresses analysis of the lower completion and especially of the individual components of the openhole MSF completion is seldom done. A comprehensive study was initiated by first validating the key data and parameters, multi-arm caliper data in conjunction with downhole camera imaging, and review of the physical mill-out patterns of frac plugs (in cased hole completions) and ball-seats used in MSFs to understand the damage pattern. This work was supported by detailed geo-mechanical properties profiles, diagnostic injection tests analysis, and evaluation of casing integrity under anticipated fracture loads. One of the primary learnings from this study was that wellbore quality had a significant bearing on the post-frac wellbore integrity for both types of well completions. The study indicated that well profile, design, and tool placement in the well also had a strong influence on axial load distribution in open-hole multistage completions. The mode of failure in openhole multistage wells was different than those seen in cemented liners. These differences do not necessarily fall under the domain of formation movement experienced in geomechanically complex and tectonically active areas. Since reservoir uncertainties are a reality, a good wellbore quality cannot always be guaranteed. It becomes necessary to manage pipe deformation with mitigating practices. This paper provides practical solutions to pipe deformation in cemented and openhole completions. The operational workflows allow upfront assessment with analytical tools to model the stress loads. By understanding the primary factors that affect well integrity, the likelihood of casing failure can be predicted and avoided ahead of time, save fracturing costs across high-risk areas, and not jeopardize production from multimillion-dollar completions. Managing well integrity is essential for development of hydrocarbon resources while preserving the environment and assuring safety of personnel.
- Asia > Middle East (0.68)
- North America > United States > Texas > Harris County > Houston (0.28)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Loma Campana Field > Vaca Muerta Shale Formation (0.99)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Loma Campana Field > Lower Agrio Formation (0.99)
- (2 more...)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- Well Completion > Well Integrity > Zonal isolation (1.00)
- (4 more...)
Distributed Acoustic Sensing (DAS) is a technology that enables continuous, real-time measurements along the entire length of a fiber optic cable. The low-frequency band of DAS can be used to analyze hydraulic fracture geometry and growth. In this study, the low-frequency strain waterfall plots with their corresponding pumping curves were analyzed to obtain information on fracture azimuth, propagation speed, number of fractures created in each stage, and re-stimulation of pre-existing fractures. We also use a simple geomechanical model to predict fracture growth rates while accounting for changes in treatment parameters. As expected, the hydraulic fractures principally propagate perpendicular to the treated well, that is, parallel to the direction of maximum horizontal stress. During many stages, multiple frac hits are visible indicating that multiple parallel fractures are created and/or re-opened. Secondary fractures deviate towards the heel of the well, likely due to the cumulative stress shadow caused by previous and current stages. The presence of heart-shaped tips reveals that some stress and/or material barrier is overcome by the hydraulic fracture. The lobes of the heart are best explained by the shear stresses at 45-degree angles from the fracture tip instead of the tensile stresses directly ahead of the tip. Antennas ahead of the fracture hits indicate the re-opening of pre-existing fractures. Tails in the waterfall plots provide information on the continued opening, closing, and interaction of the hydraulic fractures within the fracture domain and stage domain corridors. Analysis of the low-frequency DAS plots thus provides in-depth insights into the rock deformation and rock-fluid interaction processes occurring close to the observation well.
- North America > Canada > Alberta (1.00)
- North America > United States (0.67)
- North America > Canada > British Columbia > Western Canada Sedimentary Basin > Alberta Basin > Montney Formation Field > Montney Formation (0.99)
- North America > Canada > British Columbia > Western Canada Sedimentary Basin > Alberta Basin > Montney Formation (0.99)
- North America > Canada > Alberta > Western Canada Sedimentary Basin > Greater Peace River High Basin > Pouce Coupe Field (0.99)
- (2 more...)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring > Production logging (1.00)
Abstract Multi-stage, multi-well completions cause pore-pressures to increase around each stage treated, compound from earlier offset treatment stages, then dissipate as the injected fluid leaks off into the rock formation. Rock stresses change in a dynamic fashion from virgin reservoir stress to an altered stress influencing subsequently treated stages which can restrict slurry propagation from these injections into regions experiencing excess stress. Stress shadows are time-dependent and dissipate over time and return to the virgin stress state. Microseismic focal mechanisms detected from a high-fold wide azimuth surface array can be used to observe and calculate stress changes in the reservoir and constrain the time it takes for stresses to return to the virgin reservoir state. Operators can take advantage of stress changes and contain fractures close to the stages by building stress wedges around subsequently treated stages. After stress dissipates fluid propagates into previously opened fractures leading to poor fracture containment. In this paper, we review the effects of time-dependent stress shadows on multi-well completions in the Wolfcamp Formation in Southeast New Mexico. Then radioactive tracer data from the Niobrara Formation in the Denver-Julsburg basin is analyzed to provide further verification of the time-dependent process. Increased stresses from previous treatments remain elevated for ∼7 days which push fluid injected on neighboring wells away from the stress shadow. Production of well-specific tracer corroborates the hypothesis that local stress-shadows are elevated for ∼7 days which can push fluid from subsequent neighboring wells. After stresses dissipate through the fractures created during the initial stimulation, new tracer on offset wells was produced as much as 3,000 ft away on a neighboring well. Introduction Microseismic monitoring is a proven technology for observing and mapping reservoir response to hydraulic fracture stimulations. The event radiation pattern of the P-wave first arrival reveals advanced characteristics of the fracture describing deformation at the source location when detected using a high-fold wide azimuth surface array. The full-moment tensor can be generally decomposed into the relative percentages of isotropic, double couple and compensated linear vector dipole components (e.g. Aki and Richards, 1980) which fully describes the failure process in terms of volume change, amount of shearing, and other complexities related to deformation. The local stress field can be calculated using a set of focal mechanisms by minimizing the misfit angle between the modeled stress field and the observed focal mechanism slip vectors (Angelier, 1989) where the local stress field extent is defined by the spatial extent of the observed focal mechanisms. The local stress field orientation and relative magnitude can be resolved for a group of microseismic focal mechanisms by minimizing the misfit angle between the modeled stress field and the observed focal mechanism slip vectors for the subsets using a method described by Vavrycuk, 2014.
- North America > United States > New Mexico (0.55)
- North America > United States > Texas (0.35)
- North America > United States > Wyoming (0.34)
- (3 more...)
- North America > United States > Wyoming > Laramie Basin > Niobrara Formation (0.99)
- North America > United States > Wyoming > DJ (Denver-Julesburg) Basin > Niobrara Formation (0.99)
- North America > United States > Texas > Permian Basin > Wolfcamp Formation (0.99)
- (7 more...)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Tracer test analysis (1.00)
Abstract Fortin de Piedra is an important unconventional field in Argentina's Neuquén basin with over 100 horizontal gas producer wells in the lower Vaca Muerta formation. Extensive multi-stage hydraulic fracturing operations provided a spatial mapping of operational variables such as pre- and post-fracturing instantaneous shut-in pressures, or ISIP. Such ISIP magnitude maps revealed spatial patterns that correlated with the presence of structural faults interpreted from seismic data. Because of the relationship between ISIP and relevant geomechanical variables (and associated phenomena) involved in hydraulic fracturing operations, a detailed geomechanical model was constructed and employed in an attempt to explain such variations in ISIP magnitudes. The target lower section of Vaca Muerta shale formation shows a high lateral depositional continuity in the Fortín de Piedra field, allowing seismic inversion products to be used as an input for the population of the geomechanical model. Still, structural faults crossing the Vaca Muerta formation were the primary hypothesis for the source of local variation of the stress field, associated to the stress relaxation caused by rock matrix degradation in the region nearby interpreted faults planes. The model made use effective medium theory for mechanical property degradation in the vicinities of the faults that crossed Vaca Muerta formation. The mechanical properties of the near fault-elements were set to match the local trend of variation in the minimum total horizontal stress that was seen in nearby ISIPs. The ISIPs mapping signatures were captured in many of the analyzed faults. They appeared to show a horizontal stress relaxation region near the central part of the fault and a stress concentration region near the tip. With this model, we could integrate quantitatively ISIPs measurements and drilling events that would have remained unexplained with a model without faults. This novel approach allows us the systematic usage of spatially distributed by-products of hydraulic stimulation operations, to be incorporated in the process of building a geomechanical model for future planning and prognosis of undeveloped sequences of the Vaca Muerta formation within the Fortín de Piedra field.
- South America > Argentina > Neuquén Province > Neuquén (1.00)
- North America > United States > California > San Francisco County > San Francisco (0.29)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Petroleum Play Type > Unconventional Play > Shale Play (0.89)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.57)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- South America > Argentina > Neuquen > Neuquen Basin > Fortin De Piedra Field (0.99)
- Oceania > Australia > South Australia > Cooper Basin (0.99)
- (8 more...)
- Well Drilling > Wellbore Design > Wellbore integrity (1.00)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
Abstract The importance of interpretation through DFITs in characterizing reservoirs is widely recognized, leading to their incorporation into major commercial PTA software packages. However, certain limitations inherent in classical methodologies, especially for low-permeability reservoirs, have been overcome through the adoption of type-curve interpretation methodologies (Craig, 2014), and whose advantages have been exposed by Gonzalez and Arhancet (2022). Given the complexity and lack of available tools for employing this methodology, a hybrid team with technical and programming expertise developed a Python application that facilitates the integration of this new methodology and makes it accessible to all technical staff within the company, increasing efficiency and saving costs. The use of type-curve methodology offers a significant advantage in the interpretation of initial pressures, transmissibility, and permeability in low-permeability reservoirs, which could not be obtained using classical techniques. Until now, this new workflow has been carried out using spreadsheets in a handmade and rudimentary manner, requiring considerable time from the user. Although the data is often available, spreadsheets methodology makes interpretation difficult for end users, and it is very time compsuming. To address this issue, an ad hoc Python application was developed, using popular libraries such as pandas and matplotlib. This application allows users to interact with multiple screens to load and preprocess data in an agile, intuitive, and standardized manner. The development of an application with a standardized and well-organized workflow significantly improves the quality and efficiency of interpretation, especially for users with less experience. Having such a tool reduces the need to understand the functioning of spreadsheets and decreases the possibility of errors. The use of this application allows for maintaining an updated database with more than 200 records in a consistent manner. In addition to the benefit related to data interpretation, in-house hybrid team development allowed for faster time to value and enabled the tool to be developed in an agile manner, adapting to business needs. This means lower costs compared to other development methods, such as hiring a programming company or adopting commercial software. Having a tool that is currently not available in commercial software allowed for the consolidation of this methodology, which was already being used in a more handmade way and enabled the valuation of a large number of DFITs that could not be interpreted with the classical methodology. Having updated databases improves the quality of subsequent analyses (correlations, mappings, etc.). The tool has both the classical and type curve methodologies in a single environment, allowing the user to perform a complete analysis without the need for other software. In future steps, an upgrade will be made to include interpretation of post-frac fall offs. And although the application was born for a specific need for unconventional formations, its use can be extrapolated to any formation type.
- North America > United States > Texas (0.47)
- South America > Argentina > Patagonia Region (0.41)
- South America > Argentina > Neuquén Province > Neuquén (0.41)
- North America > Canada > Alberta (0.28)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Field > Vaca Muerta Shale Formation (0.98)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- (5 more...)
Mapping the Magnitude Sv-ISIPc in a Shale Gas Field and Some Considerations for Stimulation
Alvarez, Pablo (YPF S.A) | González, Cristian (YPF S.A) | Romero, Nicolás (YPF S.A) | Merchan, Vladimir (YPF S.A) | Tarrés, Gustavo (YPF S.A) | Sánchez, Mauro (YPF S.A) | Askenazi, Andrés (YPF S.A) | Rossi, Juan (YPF S.A) | Ceccon, Daniela (YPF S.A)
Abstract It is well known that Vaca Muerta oil and gas production comes from horizontal wells with multiple hydraulic fracture stages. It is desirable from an economic standpoint to get more Stimulated Reservoir Volume (SRV) per well, thus increasing the length of horizontal well paths has been a common practice through the years. The SRV per stage is mostly related to the stress regimen (described by the Vertical Stress Sv, the Minimum Horizontal Stress Sh and the Maximum Horizontal Stress SH), mechanical properties around the well and the stimulation design. According to the relative values of the Sh, Sv and SH, hydraulic fractures will tend to be vertical where normal to strike slip stress regimes are present. On the other hand, hydraulic fracture could propagate with preferred horizontal components when the state of stress is close to reverse stress regime, leading to a smaller SRV. Therefore, mapping the variation of stress state may be helpful to aware zones with low anisotropy, to take actions from the fracture design viewpoint, to optimize the full field development (pad locations) and to understand some issues during stimulation (screen out, high pressure/lower rates, casing deformation, etc.). The objective of this work is to estimate the stress regime state across the field (and along the wells) using the relative magnitude between the overburden (Sv) and a proxy of the horizontal minimum stress (Sh). In this case, the pre-frac instantaneous shut-in pressure (Pre-frac ISIP) was used as an indicator of minimum stress for each fracture stage. Also considering the availability of closure pressure data from DFITs (Diagnostic Fracture Injection Test), a correlation has been established between ISIPs values and closure pressure (Pc), leading to a corrected ISIP value (ISIPc) for a rough estimation of Sh per stage. Density logs, topography and structural position involving each horizontal length were considered in the estimation for Sv. Mapping the relationship (Sv-ISIP) and (Sv-ISIPc) along the block could show some useful variations (tendences) to be considered in the full field development.
- North America > United States (0.69)
- South America > Argentina > Neuquén Province > Neuquén (0.46)
- South America > Argentina > Patagonia Region (0.28)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.40)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Tordillo Formation (0.99)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- (5 more...)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Drillstem/well testing (1.00)
Data and Model Base of Customized Hydraulic Fracturing for Continental Shale Oil
Mei, Qiliang (PetroChina Changqing Oil Company) | Ma, Fujian (SLB, China) | Lei, Qihong (PetroChina Changqing Oil Company) | He, Youan (PetroChina Changqing Oil Company) | Luo, Yin (SLB, China) | Wang, Bo (PetroChina Changqing Oil Company) | Niu, Li (SLB, China) | Liu, Yuan (SLB, China)
Abstract The challenges of lacustrine shale oil reservoirs include not only subsurface heterogeneity of reservoir quality and but also the effect of natural fractures on propagation of hydraulic fractures and associated fracture hits. The intercalated sandstone and shale in a gravity deposit setting result in significant variation in the reservoir quality. Meanwhile, the subsurface conditions become even more complicated when the reservoirs are naturally fractured. The objective of this study is to characterize reservoir quality, natural fractures, and completion quality with well, seismic, and fracturing data, eventually to provide a base for a customized fracturing job according to the local geology aiming to enhance reservoir recovery. A geological model and a geomechanical model were built integrating all available data, including logs, core data, and seismic data, and an ant-tracking algorithm was used with variance of the seismic data as the input to delineate natural fractures. The quality check was performed by comparing drilling data, microseismic data, and fracturing data. A distributed fracture network (DFN) model was built with the ant-tracking results. Fracture stability analysis was performed when the natural fracture model and geomechanical model were ready. The fracturing design was customized and optimized with the models mentioned above and understanding obtained from the analyses. Different fracturing strategies were applied to each stage and to each well of the same pad based on the geoscience models. Some wells were completed with large-volume and high-rate fracturing practice to maintain the long-term reservoir pressure. Alternatively, some wells were subject to an intensive staging with low-volume and low-rate fracturing practice to create better near-wellbore flowing conditions. The combination of customized fracturing design and real-time adjustments during execution was approved to be a valid and practical geoengineering approach. The benefit of the workflow includes not only high fracturing efficiency, but also the effects on production performance. Production data measured by multiphase flow metering showed that the customized approach results in a 20% production increase.
- North America > United States > Texas > Dawson County (0.24)
- Asia > China > Shaanxi Province (0.17)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.15)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.84)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Sandstone (0.67)
- Asia > China > Shanxi > Ordos Basin (0.99)
- Asia > China > Shaanxi > Ordos Basin (0.99)
- Asia > China > Inner Mongolia > Ordos Basin > Sulige Field > Ordos Formation (0.99)
- (3 more...)
- Well Completion > Hydraulic Fracturing (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Naturally-fractured reservoirs (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- (2 more...)
Assessing the Feasibility of Above Injection Zone Pressure Monitoring of CO2 Geologic Storage in the Williston Basin, North Dakota, USA
Chellal, Hichem A. K. (University of North Dakota, Grand Forks) | Malki, Mohammed Lamine (Los Alamos National Laboratory) | Egenhoff, Sven (University of North Dakota, Grand Forks)
Abstract This study evaluates the feasibility of above injection zone pressure monitoring (AIZ pressure monitoring) in one of the Williston Basin CO2 storage projects. This approach relies on reservoir flow-geomechanics coupled simulations to predict the pressure response in the AIZ in the case of perfect seal and hypothetical scenarios where CO2 leakage occurs along the injector or nearby legacy wells. In this study the advantages and limitations of the pressure monitoring at AIZ were evaluated and we found that while this approach is capable of accurate and early detection of CO2 leakage, it is recommended to be implemented with other direct monitoring methods as it has its limitations as was seen in two simulation cases with low permeability leakage pathways that allowed CO2 to slowly migrate to the monitoring formation without causing significant pressure changes in this later which would make such leaks undetectable if pressure monitoring is the only monitoring technique implemented in the storage complex.
- North America > United States > North Dakota (1.00)
- North America > Canada > Saskatchewan (1.00)
- Asia > Middle East > Saudi Arabia > Eastern Province (0.28)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock (0.46)
- North America > United States > Wyoming > Powder River Basin > NPR-3 > Mowry Formation (0.99)
- North America > United States > Texas > Anadarko Basin (0.99)
- North America > United States > South Dakota > Williston Basin > Bakken Shale Formation (0.99)
- (29 more...)
- Well Completion > Hydraulic Fracturing (1.00)
- Well Completion > Completion Monitoring Systems/Intelligent Wells > Remote monitoring (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs (1.00)
- (11 more...)