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.

Abstract

During 1972, severe Dakota formation fracturing treatments were evaluated using temperature surveys, primarily. Created fractures were found to propagate upward into non-pay. Thus, below the pay perforations were attempted, and successful treatment the well resulted with better productivity A Workover had similar results.

Introduction

During 1972, El Paso Natural Gas Company completed eighteen gas drilled Dakota wells, running fracture evaluation logs. Five wells had perforations placed in the bottom or below the pay zones. This was done to evaluate the upward propagation of the induced fractures and improve the fracturing treatment.

The San Juan Basin (Fig. 1) is located in the northwest portion of New Mexico on the Eastern edge of the Colorado Plateau. Most production In the Basin has a Northwestern production In the Basin has a Northwestern trend. The Dakota formation is a tight (0.01 md) gas producing sand-shale sequence, deposited primarily as a moving shoreline trending primarily as a moving shoreline trending Northwest - Southeast with some deltaic deposition in local areas. Fig. 2 is a typical Gamma Ray/Induction Resistivity log of the Graneros - Dakota zone averaging about 250 ft. thick at a depth of 6000 to 8000 ft.

Drilled on a 320 acre spacing, each well had 4 1/2 in. casing set thru the Dakota formation in a 6 1/4 in. gas drilled hole or 7 7/8 in. mud drilled hole. Each pay zone was perforated with 16 to 20 shots per zone and the perforated with 16 to 20 shots per zone and the well hydraulically fractured with 40,000 to 90,000 lbs. of 20/40 sand at about 1 lb./gal. of fresh water treated with 3% calcium chloride and 2 lbs. of friction reducer per 1000 gal. Rubber covered nylon balls were dropped during the treatment in order to treat all zones.

All of the sixteen evaluated wells shown on Fig. 3 were gas drilled.

This content is only available via PDF.
You can access this article if you purchase or spend a download.