Gas Well Fracturing Using Gelled Non-Aqueous Fluids
Authors: Smith C.F. 
Published: December 2007

This paper was prepared for the 48th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Las Vegas, Nev., Sept. 30-Oct. 3, 1973. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Gas well stimulation is frequently unsuccessful because of the formation damage created in the hard, tight sands from which gas is frequently produced. Recent testing has shown that conventional relative permeability effects thought to be induced by fracturing a gas producing sand with an oil base fluid do not, in producing sand with an oil base fluid do not, in practice, occur to the extent expected. practice, occur to the extent expected. Further, the susceptibility of a tight sand to hydrocarbon fracturing can be shown using acid response data which gives indication of potential formation damage factors. Such lab potential formation damage factors. Such lab studies have been coupled with recent operational improvements which allow the practical use of light hydrocarbons in fracturing procedures.

This paper briefly describes the lab study of sandstone response to oil and water frac systems in terms of formation damage and the development of light hydrocarbon gels which possess the properties required for successful gas well fracturing. Field case histories are discussed and results of fracturing with the hydrocarbon gels are compared with results of conventional treatments in several gas producing areas. producing areas

Introduction

Recent economic conditions have developed in the continental United States which have improved the incentives to stimulate original gas producers. Frequently, these wells produce producers. Frequently, these wells produce from low permeability sandstone formations which have resisted previous stimulation efforts. There has been increased research effort to determine how to best stimulate sandstone gas production and several new treating processes have been introduced. Each of these processes have been introduced. Each of these processes has a unique advantage in some area processes has a unique advantage in some area but, to date, no single stimulation method has been developed which can function equally well in all sandstone formations. The success of a stimulation program still lies in proper assessment of downhole conditions and developing an engineering cost-effectiveness compromise in choice of frac fluid. This compromise must consider such things as formation damage caused in the stimulation process and how much can be prevented by using special fluids before prevented by using special fluids before treating costs get out of line. When must formation damage be tolerated in order to get necessary fracture penetration? Most stimulation treatments have theoretical adverse effects. How can these effects be minimized while obtaining the desired net stimulation?