Overflush and Fracturing: Playing Poker with your Completion

Abstract

Since the inception of hydraulic fracturing, the industry has wrestled with the concept of over/under- flushing, and has always pitched this as a binary philosophy, attempting to determine/define that this is either a fundamentally good or a bad approach. This schism simply grew with the extensive development of unconventionals; the use of overflush being an inherent and fundamental requirement for an effective and economic unconventional completion sequence. This paper will demonstrate that the true answer, as any engineer would expect, is that a detailed assessment is what is required and on a case-by-case basis. The paper will describe and reference several fracturing case histories, in both the Conventional and Unconventional environments, where the application of an overflush, an underflush or an engineered approach have been assessed or applied. Rather than taking an easy headline grabbing route to perpetuate the myth that the process is a major paradigm, or simply either a good or a bad thing. This paper will discuss some of the key aspects that impact the suitability of one approach over another; and how engineering the implementation can lead to a broader range of applicability/suitability for the most economically effective outcome. This includes an appreciation of the production/economic profile and exposure to risk, which is hugely different in say an ultra-deep-water five well offshore development vs. a field development with some 100s – 1,000s of wells in a lower-cost onshore environment. The paper will describe and demonstrate some of the fundamental variables that need to be considered; attempting to elaborate on a few of the key parameters which can influence the effective outcome. The paper will also indicate that there are several different scenarios whereby any form of overflush can result in a detrimental impact on the production rate and EUR, and that these must be fully appreciated. Subtleties, related to reservoir characteristics and fracture geometry; should be examined and appreciated. Additional aspects such as how the production, drawdown and pore-pressure will be managed can also have an impact. All these considerations, and more, will be discussed, described, and referenced. While there is no doubt that the overflush debate will continue unabated, the intent of this paper is to reduce the damage (or uncertainty), one way or the other, that will result. It is an attempt, at a minimum, to ensure that the debate becomes solely a technical one related to the approaches to be taken rather than a black and white one of right or wrong. Ultimately, the paper will advise, and inform, that the approach should be fully considered, engineered in detail and tailored to each and every application and that as a result is no longer simply considered a binary question.

Differences in Care Team Response to Patient Portal Messages by Patient Race and Ethnicity

“…Prior articles have noted the substantial care team resources required to address the growing volume of patient portal messages. 7 , 8 Our findings highlight potential disparities in how those resources are allocated across patient groups. Understanding and addressing these disparities will be necessary for improving care equity and informing algorithms.…”

“…Since the start of the pandemic, secure portal messages have become an increasingly important channel for patient–care team interaction. 5 , 7 Use of text-based health care communications is likely to continue to grow, evidenced by both traditional health care institutions, such as BMC, and the growing sector of digital-first care institutions, such as Firefly and Ginger, which often rely on text-based messaging with a health coach as a first-line triage point before patients receive clinician-based care. 22 Additionally, while AI tools have been discussed as a means for triaging and responding to patient text-based requests, 15 , 16 , 23 , 24 , 25 prior work has shown that AI tools can perpetuate underlying inequalities in the data that algorithms were trained on.…”

“…Portal messages can increase patients’ access to care teams but can also place substantial burdens on health care professionals. 7 , 8 Amidst this surge in use, message triaging has become an important tool to manage physician burden. Most practices use centralized message pools where triaging nurses decide to either respond to messages themselves or forward them to another health care professional, including escalating messages to an attending physician.…”