Optimal well spacing and stimulation intensity maximizes recoveries per well, per acre, and per capital dollar while minimizing negative offset well interactions. With climate concerns prioritized, an ideal development also minimizes the consumption of natural resources and the amount of atmospheric CO₂ released from producing each barrel of oil. Abundant horizontal oil production from unconventional reservoirs reveals widespread premature transition to Boundary-Dominated Flow (BDF) relative to published estimates assuming late-life BDF transitions. The resulting overcapitalization has minimized economic returns and maximized the CO₂ generated from superfluous diesel-fueled drilling & completion activity. The provided workflow closes the model-measure-optimize loop for sustainable development.

The combined works of Clarkson and Qanbari, Jones, Khoshghadam et al., and Lapierre suggest that transitions to BDF in unconventional oil reservoirs are initiated upon average reservoir pressure dropping below bubblepoint and imply that oil and pore-volume compressibilities provide primary pre-bubblepoint reservoir drive energy. Intuitively it should follow that pre-bubblepoint oil recovery factors (RF) may be predetermined from first principles using PVT data independent of oil-in-place (OIP) or production information.

RFs for 2 Permian multi-well pads with historical transitions to BDF manifest in production are derived & combined with low uncertainty OIP to determine Recoverable OIP (ROIP). Cumulative oil recovered at known BDF transition is compared to the novel derived ROIP.

The oil recoveries at bubblepoint predetermined by combining PVT–based recovery factors with low-uncertainty OIP agree with the observed cumulative oil barrels produced upon onset of actual BDF transition to within +/-10% when 100% stimulation efficiencies are assumed (with stimulation efficiency equal to [recovered oil] divided by [recoverable OIP]). Economic returns and CO₂ release per oil barrel are estimated for the programs ‘as-is.’ The actual well spacing and stimulation intensities employed on the two disparate Permian development units are combined and used to recommend new well spacing and stimulation intensities to achieve the same 100% stimulation efficiency with maximized economic returns and minimized amounts of atmospheric CO₂ released per recovered barrel.

Traditionally, recovery factors have only served as a reactive parameter used only to ‘sanity check’ claimed oil recoveries relative to claimed OIP. The derivation of recovery factor from PVT using first principles may provide the industry with a novel proactive tool to improve the economic and environmental performance of horizontal unconventional oil development. Furthermore, the novel definition of [Recovery Factor] as being equal to [Recovered Oil] divided by [Predetermined Recoverable Oil-in-Place] may serve to enhance the optimization of both well spacing and stimulation intensities.

Additionally, known recovery factors at known recovered oil volumes combined with low-uncertainty OIP provide a novel tool for predetermining how far to offset an existing, standalone legacy producer.

BIOGRAPHY: Scott Lapierre has served in various roles in his 25 years of service to the upstream oil and gas industry.

After receiving his BS in geology from the University of South Alabama, Scott went to work for Halliburton in 1995 as a Field Engineer operating subterranean measurement equipment for drilling operations. In 2005 he joined ConocoPhillips in 2005 as a petrophysicist and began a transition from data ‘gatherer’ to ‘interpreter’.

At the dawn of the shale revolution in 2007, Scott began developing new measurement and modeling techniques for quantifying the hydrocarbon content of shales. In 2009 he joined Pioneer Natural Resources where he was instrumental in instigating their corporate transition to shale oil development via horizontal drilling.

In 2014, he cofounded PCORE, a private equity-backed E&P company designed to exploit competitive interpretation and prediction capabilities to identify shale acreage with the highest performance potential in the Permian’s Wolfcamp formations.

In 2016, after divesting PCORE to Parsley Energy, Scott founded Shale Specialists and began offering interpretations to large and small operators and equity providers. In 2017, Scott authored a controversial article on LinkedIn forewarning of unanticipated gas production and limitations to shale oil recovery that could spell trouble for the industry. Even though Scott’s predictions were validated in 2019 by a series of articles in the Wall Street Journal that clearly illuminated the shale industries inability to meet expectations, Scott’s work remains vigorously and passionately refuted by the industry.