Arizona's Holbrook CO 2 area may hold oil, gas reserves

G. Alan Petzet
Exploration Editor

Oil seeps from the Devonian Martin formation in 17-11n-10e, Gila County, 7 miles northwest of Payson, Arizona. A Core Laboratories analysis showed a Devonian sample to have 17% porosity and 34 md permeability. [16,337 bytes]
East-central Arizona's Nascent producing area [29,047 bytes]
Discovery of carbon dioxide and nitrogen near St. Johns, Ariz., in 1994 made news as a possible CO₂ source for enhanced oil recovery.

Drilling of 10 appraisal and exploratory wells this year appears to have established production capacity on two anticlines other than the one on which the 1994 discovery well was drilled. A second operator is preparing to drill wells in southern Apache County.

Now a company long familiar with this part of the Holbrook basin said the area looks like it might have commercial oil and methane potential as well.

All of this lies within 4,500 ft of the surface in east-central Arizona, and some of it might extend into west central New Mexico (see map, OGJ, May 5, 1997, p. 127).

Colorado analogs?

The area near St. Johns, Ariz., may be geologically analogous to McElmo Dome field in Montezuma County, Colo., in the Paradox basin and McCallum and McCallum South fields in Jackson County, Colo., in the North Park basin.

Both of those areas have produced CO₂ from the gas caps of reservoirs that have oil rims, said John Somers with High Plains Petroleum, Boulder, Colo. Both have produced oil commercially, and McElmo Dome provides large volumes of CO₂ for Permian basin EOR projects.

High Plains has worked around St. Johns since 1980, and Ridgeway Petroleum Corp., Calgary, has established CO₂ producibility on prospects generated by High Plains and Tucson consultant Edgar Heylmun on three anticlines: St. Johns, Cedar Mesa, and Coyote Creek.

Ridgeway's initial discovery, 1 Plateau Cattle Co., in 15-12n-29e, is on a 20,000 acre surface anticline, the St. Johns anticline. Earlier this year, Ridgeway established CO₂ producibility on the 10,000 acre Cedar Mesa anticline in 12n-28e and 7,000 acre Coyote Creek anticline in 10n-30e. The discovery well on Coyote Creek anticline, State 10-22, cut more than 300 ft of pay.

Reservoir quality is excellent. Most of the CO₂ is in members of the Permian Supai formation. Porosities of the dolomites average 25% and reach 31% or more.

By yearend, PetroSun Exploration & Production Inc. plans to drill a well to 4,100 ft on a 13,800 acre anticline in Manuel Seep Draw in 12n-24e. Main objectives are Permian Supai, Pennsylvanian Naco, and Devonian Martin dolomite (see chart, OGJ, Jan. 5, 1981, p. 118).

PetroSun, a unit of Cronus Corp., Tucson, Ariz., also plans a well on the southwest flank of the Cedar Mesa anticline. This well will be in the El Tule area, and it will test the gas cap/oil rim theory.

PetroSun plans to remain active in the Holbrook basin in 1998, said Gordon LeBlanc Jr., president.

Ridgeway meanwhile received drilling permits in late September for five wildcats in Catron County, N.M. They are projected to Pennsylvanian at 2,550-3,050 ft.

The locations lie 7-13 miles east and southeast of a Ridgeway shut-in CO₂ discovery, the 3-1 State, in 3-11n-29e, Apache County, Ariz. That well went to 1,813 ft in 1995. Ridgeway's New Mexico locations are in 4- and 36-1n-21w and 16-, 21-, and 36-1s-21w.

Shows abound

Real commerciality for this play may lie somewhere in the future, but its past is dotted with excitement and disappointments. Somers lists other area wells and tantalizing bits:

An oil seep about 7 miles northwest of Payson, Ariz., along the East Verde River emits 40-50° gravity oil from Devonian.
Pan American Petroleum Corp. reported oil shows in 12n-23e in the 1950s.
Three potash wells drilled in the 1970s between Concho dome and Manual Seep Draw had oil and gas shows, and one had 125 ft of oil-stained dolomite in four Supai zones.
Soil gas and radiometric surveys were conducted over the area between St. Johns and Springerville by Combined Drilling Ventures. The surveys led to the conclusion that "live oil" is the source of propane and butane detected in the soil.
A 1967 Tenneco well in 22-11n-28e logged three oil zones and one gas zone in Permian Supai.
Sumatra Energy Co. abandoned because no market existed a 1983 well on the Concho structure in 12n-26e that had 138 ft of Pennsylvanian gas pay.
The New Mexico State/U.S. Department of Energy 1 Alpine-Federal, a 1993 geothermal well in 23-6n-30e, Apache County, had oil shows in Permian (OGJ, Jan. 3, 1994, p. 52).
Petrosun's 15-1 New Mexico & Arizona Land Co., in 15-14n-25e, about 20 miles west of St. Johns, blew out briefly flowing pure methane from Supai in 1996. It also had oil shows in Supai at 1,034-62 ft. Petrosun set pipe to about 1,340 ft in the well, 11/2 miles southwest of Hunt and 30 miles south of Pinta Dome/Navajo Springs helium field.

Early 1980s wells cost $400,000 to 3,500 ft. Now an operator can drill to the same depth using salt based mud that prevents problems in Permian for about $215,000. In fact, Ridgeway's 1994 discovery well cost $130,000.

Markets beckon

The St. Johns area play hasn't notched into the commercial production column yet, but markets seem available.

Willbros of Tulsa is studying feasibility of a 300 well gathering system and a 30 in., 590 mile pipeline that would ship CO₂ for EOR in giant Elk Hills oil field near Bakersfield, Calif.

It's about 60 miles from the St. Johns-Springerville area north to an existing gas pipeline corridor along Interstate 40 highway, but two large coal-fired electric generating stations at St. Johns have expressed interest in switching to gas if eventual reserves volumes support long term use.

Minimum reserves needed are 2 tcf of CO₂ for the pipeline to California and 2 tcf of methane for the local power plants.