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Recent natural and anthropogenic events, such as Hurricanes Katrina and Rita and the Deepwater Horizon oil spill, have identified significant gaps in our ability to predict risks associated with offshore hydrocarbon production as well as our capabilities to respond to deleterious events of varying scope, magnitude, and duration. As offshore hydrocarbon development in the Gulf of Mexico continues to push into new territory, there is a need to develop computational tools that enable the rapid prediction of outcomes associated with unexpected hydrocarbon release events from deepwater and ultra-deepwater systems in the Gulf of Mexico. To date, no comprehensive system-wide tool exists that can simulate the complexities of engineered-natural systems and provide the baseline data that is required to drive the simulations.To address this gap, we are developing the Gulf of Mexico Integrated Assessment Model (GOM IAM), the first coordinated platform that will allow for independent, rapid-response, and science based predictions providing the capabilities to assess risks and potential impacts associated with deep and ultra-deep water drilling in the Gulf of Mexico. This predictive model and its analyses allow for the assessment and quantification of risks and environmental impacts from deepwater and ultra-deepwater oil and gas drilling and production, as well as provide a robust tool and database that can provide crucial information necessary for the response and recovery following future loss of control events. Once the GOM IAM is developed, it can be utilize to: if) identify potential risks; ii) identify technology gaps, iii) improve our understanding of the degree of uncertainty relative to key systems and interactions associated with deep and ultra-deep water offshore hydrocarbon development to promote safer development and operations, and iv) run scenarios to serve as a baseline rapid response tool for any future oil spill events.

Optimizing a well's hydraulic fracture design within a pad development environment is a multi-disciplinary effort and requires a 4-dimensional understanding of the reservoir. This paper presents a workflow that uses an integrated workflow that combines geology, and geomechanics to build a reservoir model which can be interrogated and updated with a geologically and geomechanically constrained grid-based 3D planar frac model and production simulation using a fast marching method. In this case, as applied to an Eagle Ford well to address concerns of completion optimization, production and depletion forecasting, well spacing and well interference. The workflow captures the variability of stresses and rock properties along the wellbore and around it by using multiple geologic and geomechanical approaches. The estimated variability of rock mechanical properties is used as input in a 3D planar frac simulator. An alternative approach to geoengineering a completion, using the differential stress derived from geomechanical simulation that overcomes the limitations of well centric methods, is also illustrated. The frac design results are used as inputs/constraints in a new reservoir simulator that was developed using the Fast Marching Method to estimate drainage area. This allows for a constrained, yet extremely fast estimate of the EUR and resulting pressure depletion, addressing the important concerns of well spacing optimization and prevention of frac hits and well interferences, all in a timely manner. The integrated approach facilitates adaptive frac design which honors in-situ conditions including stress field heterogeneity, stress shadow effects and the pressure depletion from nearby producing wells. The proposed workflow enables greater investment efficiency and promotes field development optimization.

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Productivity of hydraulically stimulated unconventional wells depends greatly on the successful interconnection of the enhanced permeability and the natural fracture system. Such success is achived by proper understanding of the distribution of mechanical properties of the rock, presence of natural fractures, and regional stresses characterisitcs. With this understanding of the reservoirthe response of the rock to the stimulation can be quantified. Currrently, there are multiples approaches adopted by the industry to support such a process, making fracture designs more robust and reliable. However, theseworkflows often neglect the underlying physics of pressure wave propagation throughout the reservoir, crossing geological features such as faults, natural fractures, ash and karst layers among others. Pressure depletion caused by production of the first well in a section (parent well) generates continuous changes in stress magnitude and orientation. Simplistic geomechanical models ignore such effects and usually are built based on original conditions, resulting in overestimation of induced strain which will be reflected in oversized hydraulic fracture jobs that negatively affect not only the subsequent wells (child wells) but also the first well in section itself. Negative effects such as frac hits are usually irreversible, and proper estimation of the potential damage needs to be quantified and understood in order to put in place a mitigation plan. This work presents a workflow where changes in the pressure field are incorporated and taken into consideration during geomechanical modeling of induced strain using full continuum mechanics. As a result, hydraulic fracture designs are adjusted to the reservoir conditions at the time a new child well will be drilled and completed, thus reducing thepotential for negative effects such as frac hits. A fracture design for a planned child well to be drilled after two years of production of its parentis presented under two scenarios: first, ascenario ignoring the effect of pressure depletion, second, a scenario using the full continuum geomechanical solution to account for the effects of parent depletion. Results of the fracture design are migrated to dynamic simulation to estimate the effect on the resulting EUR.