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arXiv · 2011.13520

Diversity Dependent Uncertainty Management for Hydrocarbon Stimulation in Uncertain Heterogeneous Reservoir with Improved Efficiency

Abstract

The history of oil and gas well stimulation through hydraulic fracturing is characterized by a pursuit of optimal designs tailored to reservoir properties. However, as with many engineering systems, the impact of variability and uncertainty (in this case of reservoir properties) is not accounted in these deterministic approaches. We propose an expansion of the principle of design diversity wherein the focus becomes developing optimal portfolio combinations of multiple designs rather than repeated application of a single design. This approach can substantially increase efficiency and decrease risk when designing systems where outcome desirability is definable as a smoothly-varying efficiency and where risk is related to the variance of outcomes tied to uncertain variability of the design environment. For the case of oil/gas wells, we demonstrate diverse portfolios of designs can improve stimulation efficiency by nearly a factor of four and cut risk associated with variability and uncertainty of outcomes by over 80%. Hydraulic fracturing optimization is therefore fundamentally dependent upon uncertainty, and a change of approach toward the pursuit of design diversity can have a profound impact on efficiency and risk, and in turn cost and environmental impacts, in oil and gas development.

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Cheng Cheng. 2020-11-27. Diversity Dependent Uncertainty Management for Hydrocarbon Stimulation in Uncertain Heterogeneous Reservoir with Improved Efficiency. https://arxiv.org/abs/2011.13520

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