Abstract

University Lands' production and revenue are driven by over 270 operators in the Midland and Delaware Basins, warranting a Permian-wide study of underperforming wells. The Texas Oil and Gas Institute has access to all well data on University Lands, upholding production optimization objectives by identifying underperforming wells and determining whether production from these wells can be improved either by refracturing or artificial lift optimization. This study develops a thorough workflow to identify 300 underperforming wells out of the roughly 1,800 total horizontal Wolfcamp, Third Bone Spring, and Lower Spraberry unconventional wells on University Lands.

The team first constructed two sets of type curves were constructed for each assigned geologically similar area—P50 based on production and P10 based on recent completion intensities. We then developed and calibrated numerical models for various Wolfcamp benches and the Lower Spraberry formations to forecast what each well could produce at a given lateral length. We then compared each well's normalized cumulative production and EUR to these type curves over time to determine low performance. Then, we performed RTA and/or AL analyses to diagnose the underperforming reasons. We then narrowed down potential candidates to enhance production by selecting wells based on high quality reservoir, low completion intensity, and suitable wellbore quality (if known).

We determined that these shortlisted wells are potential refracturing or AL optimization candidates that University Land operators could improve despite critical commodity prices. Different completion methods over time significantly contributed to varying performance on University Land wells. For instance, larger ratios of hybrid fluid or cross-linked fluids compared to the total fluid pumped for the fracturing jobs yielded poorer performing wells. Wells considered for artificial lift optimization have marginal, daily operational costs and minimal workover times as recommendations, ensuring feasible implementation and consistent production across University Lands.

Our workflow is very flexible depending on the available data, man power and expertise. Completion, production, reservoir, and geologic data from operators are used to evaluate operators' performance on 2.1 million acres, four formations, and eight intervals. The evaluations gave a better understanding to TOGI staff engineers and geologists of best operational and field development practices, and revealed insights on the key reservoir characters, recoverable potentials, and corresponding optimal well completion design and AL strategy.

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