American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the 49th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Texas, Oct. 6–9, 1974. 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 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. 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 discussions may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.
Abstract
Many reservoir properties and hydraulically induced fracture parameters affect the pressure production behavior of a well. The effect of different reservoir properties such as permeability, hydrocarbon porosity, well spacing, reservoir permeability, hydrocarbon porosity, well spacing, reservoir pressure and different vertical fracture parameters such as pressure and different vertical fracture parameters such as fracture penetration, fracture permeability, fracture width, fracture porosity on the pressure production behavior of a well is investigated using a single-phase two-dimensional reservoir simulator which utilizes a direct solution method described by Price and Coats. Depending on the reservoir properties, there are unique fracture parameters which properties, there are unique fracture parameters which optimize the recoverable gas for a given time period.
This study indicates that the recovery factors for low permeability gas reservoirs are sensitive to the effective permeability gas reservoirs are sensitive to the effective fracture length. The fracture conductivity above about four darcys does not contribute measurably to the 30-year recovery nor does the fracture width for the same set of reservoir parameters. Fracture orientation on 320-acre spacing can change recovery by a factor of two.
Families of curves are presented which can be utilized in establishing the anticipated benefits (improved deliverability and recoverable gas) for different fracture treatment designs.
Introduction
During the past 25 years hydraulic fracturing has grown from the first small experimental treatment into a common production stimulation procedure in the oil and gas industry. With the increased demand for natural gas, coupled with improvement in wellhead gas prices, a new interest in the production of gas reserves from low permeability formations has gained momentum. These formations are sufficiently thick and porous to contain substantial amounts of gas, but have such extremely low permeability that payout of well expenses is long or impossible without payout of well expenses is long or impossible without effective stimulation.
In recent years, nuclear stimulation of low permeability reservoirs has undergone some experimentation. permeability reservoirs has undergone some experimentation. To date, three nuclear stimulation experiments have been performed. Detailed analysis of the stimulation effect of one performed. Detailed analysis of the stimulation effect of one of these experiments has been published by Lemon and Patel. The tests were successful in safely setting off the Patel. The tests were successful in safely setting off the nuclear device or devices in a single hole and the stimulation achieved has been encouraging. These tests have been performed with the active participation of the Atomic performed with the active participation of the Atomic Energy Commission, however, necessary government funding to go forward with required research has not been forthcoming.
