Modern Fracturing Revitalizes Dormant Technologies: A Case History

Abstract

Innovation continues to be a driving force within the petroleum industry, particularly in the service sector. Technological breakthroughs often differentiate winners and losers in this highly competitive environment and frequently lead to improved production and real value. Advances this century in hydraulic fracturing technologies have combined to reshape the global oil market by making tight gas and mudstone unconventional plays more viable. Conversely, technologies developed decades ago have also consistently shown new life and new applications when combined with these recent technological innovations. The successful application of a revitalized non-aqueous hydraulic fracturing fluid system, first developed in the early 90's for diesel and crude oil to tackle some of the most sensitive and technically challenging formations, is documented in this case history. A brief summary of the historical application of this fracturing fluid system and the reasons for lack of applications is included. The current application of this technology, in tandem with a new refined mineral oil based fluid system energized with CO2, found new life for stimulation of the multifaceted Vicksburg formation in South Texas. Vicksburg formation characterization, treatment designs and post-treatment well production performances are reviewed. A short formation evaluation and engineering analysis are also provided to help understand the formation-related challenges and working mechanisms for this fracturing fluid system. Offset wells completed with alternate technologies during the same time period were weighed against wells treated with the updated 1990's era technology. The revitalized system surpassed these comparative technologies in terms of both cumulative hydrocarbon production and decreased decline rates. This case history demonstrates not only the efficacy of the documented fracturing treatment design, but also the value in combining old and new technologies as an effective method to provide innovative solutions in challenging reservoirs.

Carbon Dioxide-in-Oil (C/O) Emulsions Stabilized by Silica Nanoparticles Functionalized with Oleophilic and CO2-philic Ligands

“…Single-phase energized oil solutions of mineral oil saturated with ∼25 wt % CO 2 , or two-phase mixtures of excess CO 2 and CO 2 -saturated mineral oil (e.g., 40% CO 2 -60% oil), have already been used to successfully fracture vertical wells in a water-sensitive formation . (An “energized oil” is a mineral oil that has been combined with high pressure CO 2 , typically yielding a nearly CO 2 -saturated oil.…”

Three-Dimensional Imaging and Quantification of Gas Storativity in Nanoporous Media via X-rays Computed Tomography

“…The small recovery percentage is a consequence of the tight shale matrix composed of pores with sizes ranging from 1 to 100 nm and small porosity, multi-phase flow blocking, clay swelling, slow matrix-fracture diffusion, and so on [3][4][5][6]. Characterizing shale and the gases within it is difficult because most of the matrix porosity is distributed in nanopores in organic matter and clays [7].…”