Considerations for Fracture Stimulation of the Deep Morrow in the Anadarko Basin
Authors: Davis Wirt E. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

This paper was prepared for the Oklahoma City SPE Regional Meeting, to be held in Oklahoma City, Okla., March 24–25, 1975. 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 presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is 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 discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

The Anadarko Basin of Western Oklahoma is currently one of the most active areas of the United States where drilling and development of deep formations are concerned.

The Anadarko Basin has several deep producing reservoirs and nearly all of these producing reservoirs and nearly all of these formations have to be stimulated to be commercially productive.

The objective of this paper is to give reference to the stimulation of the deep Morrow formation.

Considerations for designing a hydraulic fracturing treatment to stimulate the deep Morrow formation are discussed to show the value of recently developed fluids, equipment, and techniques in deep well stimulation.

Case histories are reported for wells where hydraulic fracturing treatment designs were made using the information discussed in this paper.

Introduction

Ever since the discovery of gas in the shallow Permian Carbonates of the Panhandle Hugoton field in 1918, the Anadarko Basin as seen in Fig. 1, has been a major source of gas for the entire United States.

Reserves of up to 50 billion cu ft of gas per well have been found in the deeper part of per well have been found in the deeper part of the Anadarko Basin and this has made the deep basin an enticing area to look for major gas reserves.

One continuing deep play which has spread across the entire basin is the Morrow formation. Reserves in these sands range from 10 billion cu ft per well up to 50 billion cu ft per well, depending on the thickness of the sand.

To obtain commercial production of these reserves, most of the Morrow reservoirs must be hydraulically fracture stimulated.

Some of the formation parameters that are important to the design of a hydraulic fracturing treatment are bottom-hole treating pressure, reservoir pressure, permeability, porosity, rock hardness, and formation temperature.

The deep Morrow formation below 14,000 ft is a hard sandstone reservoir with an elastic modulus ranging from 6 × 10(+6) to 7 x 10(+6) psi.

The reservoirs have bottom-hole treating pressures ranging from 12,550 psi to 20,300 psi pressures ranging from 12,550 psi to 20,300 psi with bottom-hole treating pressure gradients (frac gradients) being 0.81 psi/ft to 1.07 psi/ft. psi/ft. The reservoir pressures in the deep Morrow range from 10,900 psi to 15,800 psi with the gradients being 0.7 psi/ft to 0.86 psi/ft.