Understanding Unconventional Reservoir Fracturing: A Transdisciplinary Methodological Approach

Abstract

A better understanding of hydraulic fracturing behavior is even more crucial in unconventional plays as more new-well or infill-well are drilled and completed nowadays. Having integrated different sources of information/data such as the general trend of hydraulic fracturing practices during the last 20 years, DFIT and fracturing simulation, core analysis data, outcrops, the Hydraulic Fracturing Test Site (HFTS), and fracturing monitoring in the wells or between wells such as pressure, tracers, DAS, DTS, DSS and so on, we proposed an innovated conceptual model of hydraulic fracturing coming along with some associated concepts; The transdisciplinary integration approach we used in this research follows all fundamental physics law and meticulously logical reasoning and analogy with crossing validation, the first principle thinking epistemologically because of the physics of unconventional fracturing is much more complicated than any single discipline can explain. More often than not, the solution coming from any discipline or data source is not a unique one. The cognition of the morphology or the called fracture pattern of hydraulic fracturing is critical, which is virtually the conceptual model of fracturing. The conceptual model can directly impact the fracturing design and the way to evaluate actual fracturing. Using the proposed conceptual model, Fracturing Impact Volume (FIV), one can better explain what fracturing has done for unconventional plays and why it worked. With the proposed conceptual model and tossing aside the fracture network as the fracturing goal, many current fracturing practices can be improved significantly, and the way of production can be revised. This is a significant concept shifting in the unconventional fracturing arena, and it is certainly not an easy task, but this paper makes a compelling case. With the FIV model in mind, the perception of “the greater the pumping rate, the better the fracturing be” becomes unnecessary or makes little sense. This paper will decode the shale oil/gas flow mechanisms and demonstrate a better way to fracture and produce unconventional resources like shale oil/gas.

Evaluation of Chang 2 Reservoir in Zichang Area, Ordos Basin

“…In recent years, the field of petroleum geology in China has been greatly developed, and the way of "throwing straw hat and selecting well location" has gradually changed into the way of supporting theory and practice (Wang & Shi, 1999;Nie et al, 2000;Housekneeht, 1987), and the geological model of oil-gas reservoir and computer three-dimensional model have been established (Best et al, 2009;Amaefule et al, 1993;Cross, 1993). There are these changes in reservoir classification evaluation: 1) from macro to micro; 2) from qualitative to quantitative; 3) from single to comprehensive; 4) from the emergence of new technolo-gy to application (Weimer, 1994;Qiu et al, 1997;Wang, 1985;Mu, 1999).…”