The geology of the Pinta Dome-Navajo Springs helium fields, Apache County, Arizona

Item Type text; Thesis-Reproduction (electronic); maps

Authors Dunlap, Richard Edwin, 1943-

Publisher The University of Arizona.

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Link to Item http://hdl.handle.net/10150/552036 THE GEOLOGY OF THE PINTA DOME-NAVAJO SPRINGS

HELIUM FIELDS, APACHE COUNTY, ARIZONA

by

Richard Edwin Dunlap

A Thesis Submitted to the Faculty of the

DEPARTMENT OF GEOLOGY

In Partial Fulfillment of the Requirements For the Degree of

MASTER OF SCIENCE

In the Graduate College

THE UNIVERSITY OF ARIZONA

19 6 9 STATEMENT BY AUTHOR

This thesis has been submitted in partial fulfillment of re­ quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library.

Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg­ ment the proposed use of the material is in the interests of scholar­ ship. In all other instances, however, permission must be obtained from the author.

SIGNED:

APPROVAL BY THESIS DIRECTOR

This thesis has been approved on the date shown below:

j/'dujy. P c ,* - £c£ 1213. w. d. * m Date Professor of Geology ACKNOWLEDGMENTS

The author wishes to express his appreciation and thanks to

Dr. Willard D. Pye for his direction, patience and helpful criticism

throughout the preparation of this thesis. Sincere appreciation is

also extended to Dr. Joseph F. Schreiber, Jr., and Dr. Richard F. Wilson

for their valuable comments and assistance in the revision of the text.

The author also wishes to thank Mr. John I. Fisher of the Kerr-

McGee Corporation for providing specific well data and production in­

formation for the Pinta Dome field.

Special acknowledgment is due the personnel of the Arizona

Bureau of Mines and the Arizona Oil and Gas Conservation Commission

for their assistance in providing sample cuttings, well logs, and other

valuable information.

A very special kind of appreciation is extended to my wife,

Mary Alice, for the typing of this manuscript and her patience through­

out my graduate study.

i i i TABLE OF CONTENTS

P a g e

LIST OF ILLUSTRATIONS...... v i

LIST OF TA B LE S...... v i i i

ABSTRACT ...... ix

1. INTRODUCTION ...... 1

Purpose of Study r—i cm

Location and Accessibility . . cn

Physiography ...... o v o v m m m vj* Previous Investigations . . . .

2. METHODS OF STUDY ......

Electric and Radioactivity Logs Sample Cuttings ...... Core Sam ples ...... Field Investigation ......

3. GEOLOGY...... 7

Regional S e ttin g ...... 7 S tratig rap h y ...... 9 Precambrian Basement Rocks ...... 11 Pre-Supai Unconformity ...... 11 P ennsylvanian(?) and PermianSystems ...... 11 P re -T ria ssic Unconformity ...... 16 Triassic System ...... 16 P re -T e rtia ry Unconformity ...... 24 T e rtia ry S y s t e m ...... 24 Quaternary System ...... 27 S t r u c t u r e ...... 27 F o l d s ...... "...... 27 F a u l t s ...... 32 Other F e a t u r e s ...... 35 Origin of Structures ...... 35

4. SUMMARY OF PINTA DOME AND NAVAJO SPRINGS HELIUM FIELDS .... 36

H isto ry of Development ...... 36 S t r u c t u r e ...... : ...... 39

i v V

TABLE OF CONTENTS—Continued

P a g e

Pinta Dome F ie ld ...... 39 Navajo Springs Field ...... 40 Helium-Bearing S tra ta ...... 40 Coconino Sandstone ...... 41 Chinle Formation ...... 41 R eservoir P ressure ...... 44 Gas-Hater C o n ta c t...... 44 Q uality of the G a s ...... 45 P r o d u c t i o n ...... 45 U n i t i z a t i o n ...... 47 R e s e r v e s ...... 48

5. ORIGIN OF TERRESTRIAL H ELIU M ...... 50

6. RESULTS AND CONCLUSIONS...... 55

APPENDIX A: TOWNSHIP PLATS SHOWING LOCATIONS OF DRILL HOLES IN THE PINTA DOME-NAVAJO SPRINGS A R E A ...... 57

APPENDIX B: WELL DATA FOR THE PINTA DOME-NAVAJO SPRINGS AREA...... 62

APPENDIX C: CHANGES IN DESIGNATION OF WELLS AND CORRECTED ELEVATIONS IN THE PINTA DOME-NAVAJO SPRINGS AREA...... 69

LIST OF REFERENCES...... 70

# LIST OF ILLUSTRATIONS

Figure Page

1. Index Map Showing Location of Area of Study ...... 3

2. Index Map of Northeastern Arizona Showing Location of Major Geologic F eatu res ...... 8

3. Generalized Section of Sedimentary Rocks Exposed at the Surface and Encountered in the Subsurface in the Pinta Dome-Navajo Springs Area, Apache County, A r iz o n a ...... 10

4. Geologic Map of the Pinta Dome-Navajo Springs A r e a ...... in pocket

5. Correlation Chart of Permian Rocks in Northeastern A r iz o n a ...... 13

6. A Typical Electric-Gamma-Ray Log From the Pinta Dome- Nava jo Springs A r e a ...... in pocket

7. Correlation Chart of Triassic Rocks in Northeastern Arizona ...... 18

8. View Overlooking Part of the Pinta Dome-Navajo Springs A r e a ...... 26

9. Structural Contour Map on the Top of the Coconino S a n d s to n e ...... in pocket

10. P in ta Dome CrossSection A-A* (North-South) ...... in pocket

11. Pinta Dome-Navajo Springs Cross Section B-B' (East- West) ...... in pocket

12. Navajo Springs Cross Section C-C1 (North-South) .... in pocket

13. Topographic Expression of Pinta Dome ...... 30

14. View Overlooking the Southeastern Portion of Pinta D o m e ...... 34

v i v i i

LIST OF ILLUSTRATIONS—Continued

Figure Page

15. Discovery Well at the Pinta Dome F ie ld ...... 37

16. Gas-Water Contact and Isopach of Gas Pay of the Coconino Sandstone Reservoir ...... in pocket LIST OF TABLES

T a b le P a g e

1. Production Data for the Pinta Dome Helium Field, Apache County, Arizona, Prior to Unitization (January 1, 1 9 6 8 ) ...... 38

2. Production Data for the Navajo Springs Helium Field, Apache County, A rizona, (January 1, 1968) ...... 38

3. Summary of Core Analysis Data for the Pinta Dome Helium Field (Coconino Sandstone Reservoir), Apache County, A r iz o n a ...... 42

4. Summary of Core Analysis Data for the Navajo Springs Helium Field (Coconino Sandstone Reservoir), Apache County, A r iz o n a ...... 42

5. Some Typical Gas Analyses from the Coconino Sandstone R e s e r v o ir ...... 46

6. Rate of Production of Helium from Uranium and Thorium .... 51

v i i i ABSTRACT

Gas with a particularly rich helium content (8-9 percent) is currently being produced from the Pinta Dome and Navajo Springs helium fields in Apache County, Arizona. The helium is mainly associated with nitrogen and other inert gases. Only trace amounts of a few gaseous hydrocarbons are present.

A subsurface study has been conducted to describe the strati­ graphy and structure of the Pinta Dome-Navajo Springs area. The geology of each field is discussed in detail and illustrated with maps and cross se ctio n s.

Analysis of subsurface data indicates that a collapse feature may be present near the crest of Pinta Dome. It is suggested that this phenomena is probably related to the solution of Permian evaporites in the Supai Formation.

A radiogenic origin of the helium is strongly implied by gamma- ray anomalies in the lower part of the Chinle Formation. Correlation with formation tops derived from electric log analysis indicates that

the most prominent gamma-ray anomalies occur in the lower part of the

Shinarump and P e tr if ie d F o re st Members of the Chinle Form ation.

i x CHAPTER 1

INTRODUCTION

Purpose of Study

Because of the relatively high helium content (8-9 percent) of the raw gas produced from the Pinta Dome and Navajo Springs helium fields, the local area is one of considerable geologic and economic interest. It represents one of the few locations known which has been able to sustain an exploration and development program primarily for helium .

Since the discovery of the Pinta Dome and Navajo Springs fields, much of the surrounding area has been extensively drilled. As a result of this drilling activity, sufficient subsurface information is avail­ able to permit a detailed geologic study of the area. The present study was designed to gain a better understanding of the local subsurface stratigraphy and structure of the Pinta Dome-Navajo Springs area, and to determine, if possible, the relationship between the helium occur­ rence and the geology of the two fields.

Hopefully, the results of this study may be of some value not only in understanding this particular accumulation of helium, but also in serving as a guide for evaluating the potential of surrounding areas.

1 2

Location and Accessibility

The area covered by this report is 144 square miles centered around the Pinta Dome and Navajo Springs helium fields. These fields are located in central Apache County, Arizona, about 12 miles south of the Navajo Indian Reservation and 10 miles east of the Petrified

Forest National Monument (Figure 1). Both fields are entirely con­ tained within Tps. 19 and 20 N., Rs. 26 and 27 E., Gila and Salt River

Meridian. The Pinta Dome field lies primarily in the northern portion of T. 19 N., R. 26 E. and the southern portion of T. 20 N., R. 26 E.

The Navajo Springs field is located adjacent to Pinta Dome in an east­ erly direction.

The area can be reached by driving about 40 miles northeast of

Holbrook on U. S. Route 66 to the community of Navajo, Arizona. From that location there are several secondary roads which lead into the producing areas. Most of the study area is readily accessible by car.

Physiography

The Pinta Dome-Navajo Springs area is characterized by gently rolling topography and sparse vegetation cover. Elevations range from about 5,600 feet above sea level along the Puerco River to over 6,000

feet in highland areas to the south.

All streams in the area flow intermittently and drain into the

Puerco River, which eventually joins the Little Colorado River system near Holbrook, Arizona. The Puerco River is ephemeral, while the Little

Colorado River usually carries water most of the year-round. iue I. Figure

z q H 2 O H Z 3 -4 2 g H 2^-4 Monument National c E 0. C H A P Petrified Forest Adama nc 2E 2E 2E 2E R E 28 R27E R2GE R25E R24E i i l R E S E R ne Mp hwn Lcto o Ae o Study. of Area of Location Showing Map Index i J

• j— j VAT! ON i" \ z z / / / / / / / /Pinto zz/z/zzzzz/ \ . / / / / / / / / / y ......

'////////// z X a a o / Navajo yyy //z% Czz777^ Czz777^ //z% 5 0 Chambers yyy 1 1 1 1 1 1 11 z z MIL

/ z z z z z z z / z z / z z z

t ■ i ■ • * t i ) 10 UJ CO Sanders^; rrrr-T > 3 4

Previous Investigations

Although the Pinta Dome-Navajo Springs area represents a unique occurrence of helium-rich gas, it has received little attention from a geologic viewpoint.

As e a rly as 1948, S ila s Brown had recognized and mapped the su r­ face expression of Pinta Dome (Masters, 1960). Brown also recommended the location of the first test well on the Pinta structure in sec. 34,

T. 20 N ., R. 26 E.

John A. Masters (1960) published the results of a study of the helium reserves of Pinta Dome. His report included a short review of the history and general geology of the Pinta Dome area, as well as an estimate of the total field reserves.

In that same year, James W. Dean (1960) reported on the helium potential of the Navajo-Chambers area.

A preliminary geological survey of the central part of Apache

County was made by J. P. Akers (1961). It was followed three years later by a more detailed study of the geology and groundwater in that same region (Akers, 1964). CHAPTER 2

METHODS OF STUDY

Electric and Radioactivity Logs

Approximately 80 electric logs and several radioactivity logs from drill holes within the 144 square mile area of this report were available through the Arizona Oil and Gas Conservation Commission,

Phoenix, Arizona. Pertinent information such as location, datum ele­ vation, and total depth was taken directly from the logs and plotted on basic data sheets which had been prepared for each section drilled within Tps. 19 and 20 N., Rs. 26 and 27 E. In addition, selected in­ tervals of the logs were copied for use in picking formation tops and the preparation of cross sections.

Sample Cuttings

Rotary sample cuttings from 33 bore holes within the area are on file with the Arizona Bureau of Mines, Tucson, Arizona. Represent­ ative samples were selected for study to support electric log correla­ tions and lithologic interpretations. In general, the quality of the samples ranged from fair to good. Characteristics used to differen­ tiate cavings and recirculated materials from fresh cuttings were com­ parative size, roundness, and repetition of recognized lithologic types

Basic properties chosen for study were lithology, color, hardness, tex­ ture, composition, porosity, and acid solubility. Color descriptions were derived from a standard rock-color chart (Rock-Color Chart Com­ mittee, 1948). 5 6

Depth lag of samples was not taken into consideration because

rates of drilling and mud circulation were not known. There is prob­

ably little significant lag, however, because of the relatively shallow

depth drilled, and the nature of the lithologies encountered. This is borne out by the fact that in most cases formation tops as determined by sample examination agree within a few feet with those determined by

electric and radioactivity log characteristics.

Core Samples

Although whole cores were not available, core chips, on file

with the Arizona Bureau of Mines, were studied. These chips were more

valuable than the sample cuttings because they gave a much clearer and

more reliable indication of the nature of the lithologies encountered.

Thin sections were cut from selected core chips to aid in the descrip­

tion and analysis of formation characteristics.

Field Investigation

Because this study primarily involved subsurface relationships,

surface work was minimal. With the exception of the Pinta Dome area

proper, structures are largely obscured at the surface by deposits of

Quaternary sands and alluvium. Due to the lenticular nature of the

sands exposed in the Petrified Forest Member of the Chinle Formation,

and the limited number of outcrops within the study area, it is very

difficult to trace individual beds laterally for any distance at the

surface. Therefore, precise correlations between surface and subsur­

face structures are not possible over most of the area covered by this

re p o rt. CHAPTER 3

GEOLOGY

The sedimentary rocks that outcrop along the Mogollon slope

(Figure 2) are predominantly continental or marginal marine deposits ranging in age from Permian to Quaternary. Tertiary and Quaternary volcanics obscure some of the underlying strata in several areas along the Mogollon slope and the southern portion of the Black Mesa Basin.

Regional dips of the strata in this part of the state arc to the north or northeast at low angles except where interrupted by predominantly northwest trending folds. In some areas, notably around Holbrook, sur­ face structures may be modified or even controlled by the solution of

Permian evaporites (Bahr, 1962). If extensive solution occurs in the

subsurface, it may cause the overlying beds to collapse. Collapse

structures of this type may or may not be obvious at the surface de­ pending on their aerial extent and whether they have been covered by more recent deposits.

Regional Setting

From a regional viewpoint, the Pinta Dome-Navajo Springs area

is situated close to the axis of a broad, shallow structural depression

that lies between the Defiance uplift on the northeast and the Mogollon

slope to the southwest (Figure 2). Gregory (1917) recognized this fea­

ture and proposed that it be called the Tusayan downwarp. The folds

7 8

UTAH COLO. ------N. MEX.ARIZ.

BLACK o. MESA BASIN

HOPI BUTTES , VOLCANICS

O Flogstoff

Holbrook Novojo I Pinto Springs Dome

.St. Johns I

Show Low

WHITE MTS. VOLCANICS

miles

Figure 2. Index Map of Northeastern Arizona Showing Location of Major Geologic Features. 9 associated with this downwarp exhibit strong northwestern trends. Kelley

(1958) considers these northwestern trends one of the most persistent structural patterns found on the Colorado Plateau. These trends can be traced for a distance of several hundred miles from the area just south of the Defiance area through the Black Mesa Basin and into southcentral

Utah. Presumably the northwest trending folds arc products of tectonic disturbances during the Laramide Revolution of Late Cretaceous to Early

Tertiary age.

Brown (1956) recognized what he believed to be a younger, super­ imposed northeast-southwest cross trend along the southern margin of the

Navajo Indian Reservation. He is of the opinion that these northeast trending folds are probably less favorable than the northwest trending folds for the accumulation of gas and oil.

According to Brown and Lauth (1958), most of northeastern Arizona is relatively free of major faulting. Only a few faults have been rec­ ognized on the Mogollon slope and the Black Mesa Basin. The faults that have been studied appear to be high angle, normal block faults with ver­ tical displacements seldom greater than several hundred feet.

Stratigraphy

Subsurface formations recognized in the sample cuttings and logs of the drill holes within the study area include the Supai Formation of

Permo-Pennsylvanian age, the Coconino Sandstone of Permian age, the

Moenkopi Formation of Early and Middle (?) Triassic age, and the Chinlc

Formation of Late Triassic age (Figure 3). 1 0

System, or Thick­ Formation General Lithologic Characteristics s e rie s ness Q uaternary Alluvium, sand, and grave1 ...... U IN UU IN U K . M 1 1 i — Grayish-brown calcareous sandstone Bidahochi T e rtia ry 0-180 interbedded with silty muds tone and Formation volcanic ash; bentonitic ▼ r* ■ktt? r\ n \ t t ------U iN U J iU 1 U lx r lll 1 ------Reddish-brown to grayish-blue mud­ stone and claystone with some silty Chinle 650- sandstone; some limestone and gypsum Formation 850 Upper in upper portion, siltstone and con­ glomeratic sandstone in lower portion U K U U ru ' U lv rll 1 1 -----

T ria ss ic Brown to gray calcareous siltstone Moenkopi 125- and mudstone; slightly gypsiferous; Formation 150 very s i l t y Lower tc Middle(?) UINUUN1UKH11 1 "" Light gray to b u ff, fin e - to medium­ e Coconino 250- cti u grained sandstone; loosely to firmly • l-J Sandstone 325 e 3 cemented with silica u o V pH Reddish-brown sandstone, siltstone Supai and mudstone; some dolomitic lime­ 1700? Penns] Formation stone; thick interbedded evaporitic f i ­ sequence in upper portion vaniail m ' UiNuUHrUivvlll 1----- Precambrian Crystalline basement rocks

Figure 3. Generalized Section of Sedimentary Rocks Exposed at the Surface and Encountered in the Subsurface in the Pinta Dome-Navajo Springs Area, Apache County, Arizona. 11

Surface exposures in the Pinta Dome-Navajo Springs region are of the Petrified Forest Member of the Chinle Formation, the upper and lower members of the Bidahochi Formation, and Quaternary sands and alluvium

(Figure 4, in pocket).

Precambrian Basement Rocks

Because of the lack of deep drilling within the area of study, the exact position and nature of the basement rocks have yet to be de­ termined. However, projection of subsurface information from several deep oil test wells located within a 15-mile radius of Pinta Dome in­ dicates that Precambrian granites should be found at a depth of approx­

imately 3,000 feet, but this will vary depending on location.

Pre-Supai Unconformity

Lower Paleozoic rocks have not been recognized at the surface or in the subsurface in central Apache County. Instead, red beds of

the lower part of the Supai Formation are in depositional contact with

the Precambrian basement. The hiatus is probably the result of nondep­

osition in the Defiance positive area. This ancient positive area ap­

parently influenced sedimentation over a wide portion of northeastern

Arizona throughout most of Paleozoic time (McKee, 1951).

Pennsylvanian(?) and Permian Systems

Supai Formation. The age of the Supai Formation is considered

by most workers to be Pennsylvanian in the lower part and Permian in

the upper part. Huddle and Dobrovolny (1945) concluded that the Supai 12

Formation in central and northeastern Arizona probably ranges in age

from Middle Pennsylvanian to Lower Permian. Winters (1963), in his

study of the Supai Formation in eastcentral Arizona, placed an arbi­

trary Pennsylvanian-Permian boundary at the base of the Supai Formation.

Because this matter has yet to be resolved, the age of the Supai Forma­

tion in the Pinta Dome-Navajo Springs area is considered to be Pennsyl­ vanian (?) and Permian. Figure 5 shows the general relationships of the

Supai and other Permian formations in northeastern Arizona.

The Supai Formation can be subdivided arbitrarily into a lower

and upper red bed sequence separated by the marine Fort Apache Member.

The lower red bed sequence probably contains the Pennsylvanian-Permian boundary, but its exact position has not yet been determined. In the

Pinta Dome-Navajo Springs area the pre-Fort Apache portion of the Supai

Formation consists of deposits of reddish-brown to orange siltstone and

mudstone. The total thickness of these sediments is uncertain because

it has never been entirely penetrated within the study area, but it is

estimated to be about 700 feet. As of the time of this report, the

deepest well which has been drilled within the Pinta Dome-Navajo Springs

area is the Eastern Petroleum 3 Santa Fe well located in sec. 9, T. 19

N., R. 27 E. This well apparently bottomed in the lower portion of the

Supai Formation after penetrating about 430 feet of lower Supai sedi­

ments.

The marine Fort Apache Member of the Supai Formation overlies

the continental red bed deposits of the lower Supai. Only a few wells

have been drilled deep enough to reach this horizon in the Pinta Dome GRAND CANYON MOGOLLON RIM PINTA DOME AREA DEFIANCE UPLIFT ZUNI UPLIFT

Kaibab Kaibab . San Andres (Absent) Limestone Limes tone Limestone

De C helly Toroweap Sandstone Sands tone (upper) Coconino Coconino G lo rie ta Sands tone Sands tone Sands tone Coconino Sandstone

Hermit

PERMIAN SYSTEM PERMIAN Shale Yeso Formation Supai Supai Supai Formation Formation Form ation Supai Form ation Abo Formation

Figure 5. Correlation Chart of Permian Rocks in Northeastern Arizona

Source: Modified from Read and Wanek (1961). 14

and Navajo Springs area. In these wells, the Fort Apache Member is a brownish-gray (5YR4/1) dolomitic limestone some 20 to 25 feet thick.

It is not sharply defined on well logs, but is an important subsurface marker which appears in sample cuttings as a distinct lithologic break between the overlying evaporites and underlying red bed deposits. The

Fort Apache Member has been discussed in detail by Gerrard (1964).

In the vicinity of Pinta Dome and Navajo Springs, the upper por­

tion of the Supai Formation contains a thick evaporitic sequence. Total

thickness of Supai beds overlying the Fort Apache Member is approximate­

ly 1,000 feet. With the exception of the uppermost 100 feet, which con­

sist mainly of continental red bed deposits, the rest of the upper Supai

is composed of halite, gypsum, and anhydrite interbedded with reddish-

brown shaley siltstone and mudstone. This interval is well defined on

radioactivity logs (Figure 6, in pocket). The evaporitic sequence in

the Pinta Dome-Navajo Springs area forms the northeastern extension of

the Holbrook Basin which existed in parts of southcentral Coconino,

Navajo and Apache Counties during part of Permian time (Peirce and

Gerrard, 1966).

Coconino Sandstone. The Coconino Sandstone lies conformably

above the Supai Formation. It is the youngest formation of Permian

age that can be recognized in the subsurface in the Pinta Dome-Navajo

Springs area. The age of the Coconino Sandstone has been established

as Early Permian chiefly on the basis of its stratigraphic position

above the Supai Formation and below the Kaibab Limestone (Akers, 1964).

Correlations used in this report are essentially those of Read and Wanek 15

(1961)5 who propose that the Coconino Sandstone is probably equivalent to the Glorieta Sandstone of the Zuni uplift and the upper portion of the De Chclly Sandstone of the Defiance uplift (Figure 5).

The thickness of the Coconino Sandstone varies from 400 to 800 feet on the Mogollon slope, to about 200 feet in the Grand Canyon. In the Pinta Dome-Navajo Springs area the Coconino Sandstone consists of

250 to 325 fe e t of g ray ish orange pink (5YR7/2) to very pale orange

(10YR8/2), fine- to medium-grained, mature quartz sandstone. Individ­ ual grains range in size from 1/8 to 1/2 mm and are generally well sorted. Most of the grains are subangular to subrounded and commonly exhibit frosted surfaces. Quartz overgrowths on detrital grains are abundant. Interstitial porosity is generally well developed except where inhibited by cementation and other postdepositional changes. The • chief binding material throughout the Coconino Sandstone is silica rath­ er than calcareous or ferruginous cement. The Coconino Sandstone is easily recognized in sample cuttings as a very clean, light gray to buff, fine- to medium-grained sandstone. On electric and radioactivity logs, its diagnostic characteristic is a sharp kick to the left on S.P. and gamma-ray curves. Resistivity curves indicate whether the Coconino

Sandstone is gas or water bearing. High resistivity values are obtained opposite the gas-bearing horizon at the top of the Coconino Sandstone.

When the formation is water bearing, very low resistivities are recorded.

Since the Coconino Sandstone serves as the principal reservoir rock for the accumulation of helium-rich gas at Pinta Dome and Navajo Springs, it is discussed in further detail in Chapter 4 of this report. 16

An extensive study of the Coconino Sandstone and its occurrence over wide areas in northern Arizona was made by McKee (1934). In his paper he discusses environmental interpretations and observations which are considered beyond the scope of the present study.

Pre-Triassic Unconformity

The pre-Triassic unconformity situated at the base of the Moen- kopi Formation represents a period of erosion which in northeastern

Arizona extended throughout Late Permian and part of Early Triassic time (Akers, Cooley and Repenning, 1958). According to Cooley (1959), beveling of the Permian commences just west of Winslow, and becomes progressively greater eastward across northeastern Arizona. At Winslow, minor stripping of the Kaibab Formation has resulted in an essentially flat erosion surface with a local relief of one to three feet. Near

Holbrook, the unconformity has locally cut through the Kaibab Limestone and into the Coconino Sandstone. Further to the east, in the vicinity of Pinta Dome, Moenkopi sediments are found in depositional contact with the Coconino Sandstone with no Kaibab Limestone present. No evi­ dence of angular discordance has been found along the unconformity in this part of Arizona.

Triassic System

Moenkopi Formation. The Moenkopi Formation of Early and Middle

(?) Triassic age forms a wedge-shaped deposit that is over 2,000 feet thick in northwestern Arizona and Utah, and thins eastward toward New

Mexico. In the area of this report, the Moenkopi Formation consists 17 of approximately 125 to 150 feet of continental or marginal marine de­ p o s its .

McKee (1954) subdivided the Mocnkopi Formation in the area of

the Little Colorado River into three units: the Uupatki, Moqui and

Holbrook Members. Cooley (1959) described these th ree members in the

Winslow area (Figure 7). These members can be traced in the subsurface across the area of this report.

The basal part of the Wupatki Member consists of a thinly lam­

inated dark reddish brown (10R3/4) micaceous siltstone or silty mud­

stone which ranges in thickness from 20 feet in the northwestern portion of the Pinta Dome-Navajo Springs area to less than five feet in the

southeastern part. This member unconformably overlies the Coconino

Sandstone. The lower part of the Wupatki Member is easily identified

in well samples by its characteristic color and lithology and on S.P.

and gamma-ray logs by weak kicks to the left of the shale line imme­

diately above the top of the Coconino Sandstone. On resistivity logs,

the resistivity commonly increases from the base upward through the

interval. The "lower massive sandstone" described by McKee (1954) in

the Little Colorado River area is probably represented in the Pinta

Dome area by a thin, pale reddish brown (10R6/4) to light brownish

gray (5YR5/1), fine to very fine, grained silty sandstone about five

fe e t th ick which occurs near the top of the Wupatki Member. The sand

zone shows up as a sharp kick to the l e f t of the sh ale lin e on some

S.P. and gamma-ray logs, but on other logs it is poorly defined.

The Moqui Member of the Moenkopi Formation directly overlies

the Wupatki Member. W ithin the P in ta Dome-Navajo Springs area the Moqui WINSLOW AREA PINTA DOME AREA S. DEFIANCE PLATEAU NAVAJO COUNTRY (Cooley, 1959) (This report) (Cooley, 1959) (Gregory, 1917)

Lukachukai Wingate Member Sands tone Rock Point Rock P oint D ivision A Wingate

Sandstone Member Member

Owl Rock Owl Rock D ivision B Member V//////A Member Upper P a rt Upper P a rt Petrified Forest Member Sensela Sonsela D iv isio n C (Undivided) Sandstone Sandstone

P e tr if ie d Lower P a rt • P e trifie d Lower P a rt Chinle Formation F o rest Member F o rest Member Chinle Formation Mesa Redondo Lower Red Lower Red D iv isio n D Member Member Member

Shinarump Shinarump Shinarump Shinarump Member Member Member Conglomerate ///IV///////. /7ZZZZ/Z/'ZZZZZZZZJ////////) Holbrook Holbrook Holbrook Member Member Member Moqui Moqui Moenkopi Member Member Form ation

Formation Wupatki

Moenkopi Wupatki Member Member

Figure 7. Correlation Chart of Triassic Rocks in Northeastern Arizona. 19 consists of approximately 50 to 75 feet of light brownish gray (5YR5/1) to light grayish red (10R5/2) siltstone, silty sandstone and mudstone units. Variations in overall thickness of the Moqui Member arc due mainly to the arbitrary definition of the upper contact of the Moqui which is taken at the base of the lowest sandstone bed that has a li­ thology similar to the overlying Holbrook Member. Gypsiferous beds which are found in the Moqui in the Winslow-Holbrook area apparently grade into or intertongue with siltstone and silty sandstone units which arc present in the Pinta Dome-Navajo Springs area. Only a trace of gypsum was found in the w ell samples from th is in te rv a l. The S.P. log shows only minor departures from the shale line. Silty and sandy units tend to be better reflected on gamma-ray curves.

O verlying the Moqui is the Holbrook Member. In the P in ta Dome-

Nava jo Springs area the Holbrook Member is composed of calcareous, pale grayish red (10R5/2) to pale brown (5YR5/2) sandstone, siltstone and mudstone units. The sandstone is generally fine to medium grained, poorly sorted, and contains considerable silt and flakes of mica.

Thickness ranges from 35 to 70 feet in the Pinta Dome-Navajo Springs area. The Holbrook Member is well indurated by calcium carbonate ce­ ment. Interstitial porosity is limited by poor sorting, high silt con­ tent and high degree of cementation. The base of the Holbrook Member generally appears on electric and radioactivity logs as a weak to mod­ erate kick to the left of the shale line approximately 80 feet above the top of the Coconino Sandstone. 20

Prc-Chxnlo Unconformity. Numerous authors (Cooley, 1957, 1959;

Akers.and others, 1958; Akers, 1964) have discussed the pre-Chinle (pre-

Shinarump) unconformity and its occurrence in northeastern Arizona.

Cooley (1957) refers to this erosion surface as the most widespread and

"rugged" found on the Colorado Plateau. In most areas of northeastern

Arizona, pre-Chinle erosion developed a surface of moderate relief on top of the Moenkopi Formation. However, in the L ittle Colorado River area erosion was more severe, and in some places produced a surface w ith as much as 200 fe e t of r e l i e f .

Although it is difficult to determine exactly how much pre-

Chinle erosion has taken place locally in the vicinity of Pinta Dome, variations in the stratigraphic thickness of the Moenkopi Formation indicate that the total relief probably did not exceed 25 or 30 feet.

Chinle Formation. Gregory (1917) recognized four members of the Upper Triassic Chinle Formation in his study of the Navajo country.

He referred to these members informally in descending order as Divisions

A, B, C, and D (Figure 7). Since that time, in Arizona, Division A has been removed from the Chinle Formation and reassigned to the Wingate

Sandstone (Harshbarger, Repenning and Irwin, 1957); Divisions B and C have been renamed the Owl Rock and Petrified Forest Members, respec­ tively, by Stewart (1957), and Gregory (1950); and Division D is gen­ erally referred to informally as the lower red member (Akers and others,

1958). The Shinarump Conglomerate, which was formerly a separate for­ m ation, was re c la s s if ie d by Stew art (1957) as the b asal member of the

Chinle Formation. With the exception of the Owl Rock Member, each of 2 1 the other members of the Chinle Formation arc present at the surface or in the subsurface in the area of this report. Relationships between in­ dividual members are gradational or intertonguing and contacts have been chosen on the basis of changes in gross lithology and/or wire-line log characteristics.

The lithology of the basal Shinarump Member of the Chinle For­ mation varies greatly on both a regional and local scale. According to

Cooley (1959), the Shinarump Member is not a blanket-type deposit in the New Mexico-Arizona state line region. Variations in thickness and lithology are due primarily to deposition in channels produced by pre-

Chinle erosion.

In the Pinta Dome-Navajo Springs area the Shinarump Member con­ sists of a pale orange to reddish-brown conglomeratic sandstone. The sandstone consists of poorly sorted, subrounded to subangular quartz grains which range in size from 1/4 to 2 mm. Light orange, red, and green chert pebbles, 1 to 4 mm in diameter, are scattered throughout the member. Most of the chert is fairly well rounded although a few angular fragments are also present. Other less abundant constituents

include weathered feldspar fragments, petrified wood, and light gray and dark purple quartzite pebbles. Thickness of the Shinarump Member varies from 10 to 60 feet in the Pinta Dome-Navajo Springs area.

The basal contact of the Shinarump Member is generally well defined on electric logs by a moderate to strong kick to the left of

the shale line on the S.P. curve. The top of the Shinarump Member is

sometimes difficult to determine because it appears to grade upward 22 into or in terto n g u e w ith the overlying sands of the lower red member.

In most logs, the top of the Shinarump Member is separated from overly­ ing sands by a shale break which appears on S.P. and gamma-ray curves.

Since in many cases it was impossible to see any significant difference in the sample cuttings of the lower red and Shinarump Members, correla­ tions are based mainly on electric and radioactivity log characteristics.

Sediments of the lower red member overlie and intertongue with the Shinarump Member. In the Pinta Dome-Navajo Springs area the lower red consists of reddish-brown (10R2.5/3) sandstone, sandy siltstone, and mudstone units. Individual quartz grains range in size from 1/4 to

1 mm and arc predominantly angular to subangular. Light colored, weath­ ered feldspar fragments give the sands a speckled appearance. A few rounded light red chert pebbles arc also present, ranging in size from

1 to 4 mm in diameter. These constituents are generally embedded in a reddish-brown micaceous clay matrix which holds the grains together and effectively reduces interstitial porosity. The lower red member is ap­ proximately 200 feet thick in the southern Defiance area, but averages only about 50 feet in the Pinta Dome-Navajo Springs area. Sands of the lower red member appear as a series of weak to moderate kicks to the left on S.P. and gamma-ray logs. Resistivities are generally less than

those of the subjacent Shinarump Member, but g re a te r than the weak r e ­

sistivities found in the overlying Petrified Forest Member.

The Petrified Forest Member is the most widespread of all the members of the Chinle Formation in n o rth e a ste rn A rizona. In the e a s t­ ern and southeastern part of the Black' Mesa Basin, Akers and others 23

(1958) subdivided the Petrified Forest Member into an upper and a lower part separated by the Sonsela Sandstone bed.

In the Pinta Dome-Navajo Springs area the lower part of the

Petrified Forest Member consists of approximately 400 feet of grayish- blue (5PB5/2) mudstone and claystone with thin interbedded tuffaceous siltstone and sandstone units. Some reddish-brown units arc also pres­ ent, but they arc not as common as those found in the upper Petrified

Forest Member. Sample cuttings from the lower part of the Petrified

Forest Member consist of a monotonous sequence of fine-grained clastic materials. S.P. logs show only minor departures from the shale line, while resistivity curves arc characterized by extremely low values.

The medial Sonsela Sandstone is a light gray (5YR7/1) conglom­ eratic sandstone interbedded with thin layers of mudstone and siltstone.

Individual particles consist of poorly sorted, subrounded to rounded, frosted quartz grains ranging in size from 1/8 to 1/2 mm. Weathered feldspar fragments and associated argillaceous materials are also abun­ dant. Coarser material is mainly concentrated along bedding planes and consists of white, light orange, and dark red chert. These constituents are weakly bonded by calcium carbonate cement and argillaceous material.

Interstitial porosity of the sand is generally fair to good. In areas of outcrop immediately west of the study area, the Sonsela Sandstone commonly exhibits small to large scale cross stratification. The total thickness of the Sonsela Sandstone is difficult to determine within the study area. Only a few of the sands crop out at the surface, and the upper and lower limits cannot be picked with any certainty. The East­ ern Petroleum 3 Santa Fe well, located in sec. 9, T. 19 N., R. 27 E., 24 apparently penetrated about 90 feet of the Sonsela Sandstone in the subsurface.

The upper part of the Petrified Forest Member is composed pri­ marily of reddish-brown (10R5/4) mudstone and siltsto n e units inter- bedded with thin layers of gypsum and limestone. Much of the upper part of this sequence has been eroded away in the Pinta Dome-Navajo

Springs area, where thickness averages only about 200 feet as compared to 1,000 feet in some areas of southcentral Apache County. Log char­ acteristics were not determined for the upper part of the Petrified

Forest Member because most of the holes that have been d rilled were not logged through this interval.

Pre-Tertiary Unconformity

Widespread erosion of Mesozoic rocks in the Navajo country pro­ duced what Gregory (1917) referred to as the Hopi Buttes peneplain.

This erosion surface is situated at the base of the lower member of the

Bidahochi Formation of Tertiary age.

Tertiary System

Limited exposures of Tertiary deposits are found within the re­ port area. Where they occur, they occupy a position directly above the

Chinle Formation. These deposits consist of essentially flat-lying,

thin- to thick-bedded sandstone, siltsto n e, and mudstone units, some of which arc partially derived from the underlying Petrified Forest Member

of the Chinle Formation. Thickness ranges from 0 to 180 feet in the

Pinta Dome-Navajo Springs area. 2 5

Bidnhoc.hi Formation. The only formation of Tertiary age that is recognized in the Pinta Dome-Navajo Springs area is the Bidahochi Forma­ tion, Akers (1964) described three members of the Bidahochi Formation in central Apache County: a lower lacustrine member; a middle volcanic member; and an upper flu v ia tile member. Only the lower and upper mem­ bers are present in the Pinta Dome-Navajo Springs area.

The lower member of the Bidahochi Formation crops out in a lim­ ited area west of Crazy Creek in the northwestern part of the study area

(Figure 4), in another area about eight miles south of Navajo (Figure 8) and in several other localities. Exposures consist mainly of flat-lying grayish-brown (5YR4/2) sandstone, mudstone, and claystone intcrbeddcd with white volcanic ash and bentonite. These sediments commonly weath­ er into slope forming units similar to those of the Petrified Forest .

Member of the Chinle Formation, The lower member has been dated by

Lance (1954) as Late Miocene or Early Pliocene.

The upper member of the Bidahochi Formation crops out in several

locations in the eastern half of the study area (Figure 4). It is com­ posed of light brownish gray (5YR7/1) to pale yellowish brown (10YR7/2)

calcareous sandstone and silty mudstone. The sands consist mainly of

fine- to coarse-grained, poorly sorted, rounded to well rounded, clear,

frosted, and stained quartz grains, and red and green chert pebbles.

Well rounded, fine grains of magnetite are also abundant. Most of the

beds are very s ilty and well cemented with calcium carbonate. The age

of the upper member has been determined as Middle Pliocene by Stirton

(1936), and Lance (1954). 26

Figure 8. View Overlooking Part of the Pinta Dome-Navajo Springs Area.

This view was taken looking northward from a bluff approximately eight miles south of the community of Navajo. Beds in foreground belong to the Bidahochi Formation. 27

Quaternary System

Quaternary deposits are widespread in the Pinta Dome-Navajo

Springs area. Thickness ranges from zero to several hundred feet.

Within the study area, these deposits consist largely of unconsolidated

sand, gravel, and alluvium. Windblown sand occurs chiefly over broad

flat-lying areas, while accumulations of gravel and alluvium are gen­

erally confined to drainage channels and other low-lying areas.

Structure

The regional dip of the strata in the Pinta Dome-Navajo Springs

area is less than 1 degree to the northeast. The predominant struc­

tural grain of the area appears to be to the northwest although a few

structures trend to the northeast. Individual uplifts are somewhat ir­

regular and lack the continuity generally associated with folding due

to compressional forces.

The description of structures in the Pinta Dome-Navajo Springs

area is based upon the subsurface structural map drawn on the top of

the Coconino Sandstone (Figure 9, in pocket), unless otherwise indi­

cated. The reason for this is that much of the area is covered by Ter­

tiary and Quaternary sediments which mask the bedrock structure. Where

bedrock is exposed, the beds are lenticular, cross bedded, and otherwise

difficult to use to determine local structures.

Folds

Subsurface structures in the Pinta Dome-Navajo Springs area are

elongated domes or anticlines of relatively low structural relief. 2 8

Actual closure on individual structures is commonly less than 50 feet.

Irregular synclinal folds are present between the structurally high areas.

The structural contour map on the top of the Coconino Sandstone

(Figure 9) shows the subsurface structure of the Pinta Dome-Navajo

Springs area. Structural contour maps on the overlying Shinarump Mem­ ber and lower red member of the Chinle Formation exhibit essentially the same configuration.

Figures 10, 11, and 12 (in pocket) are north-south and cast-west cross sections that show the subsurface structural and stratigraphic re­ lationships in the Pinta Dome-Navajo Springs area. The line of each cross section is shown on Figure 9.

Pinta Anticline. The Pinta anticline is a northwest trending asymmetric anticline situated in the southern part of T. 20 N., R. 26 E. and the northern and central portions of T. 19 N., R. 26 E. (Figure 9).

Structural relief of the anticline is about 100 feet. The main uplift is separated into three domal highs. The northern one is usually des­ ignated as "Pinta Dome."

1. Formation tops utilized in the preparation of subsurface maps in conjunction with this report were determined by electric and radioactivity log analysis and are listed for reference in Appendix B. Surface elevations were taken directly from log headings with the ex­ ception of those wells in the Pinta Dome and Navajo Springs fields that were resurveyed prior to unitization hearings held before the Arizona Oil and Gas Conservation Commission. A list of the resurveyed eleva­ tions can be found in Appendix C of this report along with changes in the designation of certain wells which have taken place consequent to changes in ownership. 29

The topographic expression of Pinta Dome (Figure 13) approx­ imates structural conditions in the subsurface. Strata are more steeply inclined on the northern and northeastern flanks of the structure where dips approach 150 feet per mile. On the southwestern flank the beds arc only slightly inclined, and the average rate of dip is about 50 feet per mile. There is about 50 feet of closure on the structure.

The northeastern flank of Pinta Dome is cut off by the northwest­ erly striking Pinta Dome fault. The downdropped flank is a weak struc­ tural nose that extends a short distance to the northeast under portions of secs. 26 and 27, T. 20 N., R. 26 E. on the east side of the fault.

This portion of the dome is nonproductive.

The southeastern end of Pinta Dome is separated from the main part of the uplift by the northeasterly striking Navajo Springs fault.

Productive wells have been drilled on both sides of the fault in this area.

The southern part of the Pinta anticline is separated from the northern part by a shallow syncline. The southern portion is composed of two domal highs separated by a syncline. Each has a closure of over

25 feet in the subsurface, but neither has produced gas in the Coconino

Sandstone.

A small isolated dome may be present in sec. 24, T. 19 N., R.

26 E. Because of its small size and limited closure, this structure offers little or no potential as a trap for helium-rich gas. Also its presence is largely dependent upon a mineral strat test in sec. 19, T.

19 N., R. 27 E. An error in elevation or stratigraphic interpretation could easily wipe out this structure. 3 0

Figure 13. Topographic Expression of Pints Dome.

View to the southwest from access road to the Pints Dome field. Kerr McGee 2 Fee well is located near horizon left of center. 3 1

Navajo Springs. The Navajo Springs structure is a northwesterly trending anticline that occupies the extreme southwestern portion of T.

20 N., R. 27 E., and the northwestern part of T. 19 N., R. 27 E. (Fig­ ure 9). The structure is largely obscured at the surface due to. allu­ vial cover. In the subsurface, the fold is slightly asymmetric with strata dipping more steeply on the northeastern flank where dips ap­ proach 100 feet per mile. The Navajo Springs structure displays about

75 feet of relief and 50 feet of structural closure. It is cut off to the north by the Navajo Springs fault; its continuation on the north side of the fault is not evident.

The Navajo Springs structure continues southeastward as a long, plunging structural nose from the northwest corner of T. 19 N., R 27 E. into the central portion of the same township. Although this is a fair­ ly large feature, i t does not exhibit any closures south of the Navajo

Springs dome, and therefore there is little or no potential for helium­ bearing gases to be trapped in this area.

A subsidiary high is present northeast of the Navajo Springs fold in the vicinity of secs. 27 and 28, T. 20 N., R. 27 E. There is less than 25 feet of closure on this structure. The fold is cut on its northeastern side by the northwest striking Kirby fault. The structure continues north of the fault as a rising fold with no closure. One gas well is located on the high trend south of the fault. This subsidiary fold is separated from the main Navajo Springs fold by a well developed northwest trending syncline which is separated from its northern down- dropped continuation by the Navajo Springs fault. The syncline is in 3 2 the southcentral part of T. 20 N., R. 27 E. Three shut-in helium wells are located in this syncline.

Other minor plunging anticlines and synclines are found within the Pinta Dome-Navajo Springs area. Many of these are implied with lit­ tle or no structural control.

Faults

The faults which are present in the Pinta Dome-Navajo Springs area are high angle, normal faults of relatively small displacement.

The faults are generally downthrown to the north with displacements of less than 300 feet.

Pinta Dome Fault. The northwest striking Pinta Dome fault lies along the northeastern flank of Pinta Dome and separates the main pro­ ductive portion of that structure from its nonproductive downdropped flank on the northeastern side of the fault. Displacement along the fault varies from about 125 feet at the southeastern end where it in­ tersects the Navajo Springs fault, to less than 100 feet in sec. 28, T.

20 N., R. 26 E. where i t passes to the south of the Linehan 1-21 Spur­ lock well. The fault apparently continues to the northwest beyond the township line.

Navajo Springs Fault. The northeasterly striking Navajo Springs fault is downthrown on the northwestern side, and reaches a maximum dis­ placement of almost 300 feet in the subsurface. The fault can be traced

in the subsurface under portions of secs. 28, 29, 30, and 31, T. 20 N.,

R. 27 E ., secs. 35 and 36, T. 20 N ., R. 26 E ., and secs. 2, 3, and 10, 3 3

T. 19 N., R. 26 E. The fault is not evident at the surface within the

Navajo Springs area because of allu v ial cover. However, numerous fresh­ water springs located in sec. 29, T. 20 N., R. 27 E. may be related to

this feature. At Pinta Dome, a conspicuous break in the surface topog­ raphy in sec. 2 and 3, T. 20 N., R. 26 E. is probably the surface ex­ pression of the Navajo Springs fault (Figure 14). Displacement along

this part of the fault decreases to the southwest, and the fault cannot be traced at the surface or in the subsurface beyond sec. 10.

Kirby Fault. The northwest striking Kirby fault bounds the

Navajo Springs field to the northeast and cuts off the minor anticline

which lies northeast of the main Navajo Springs structure. Displace­

ment of the fault is approximately 200 feet, with the downthrown block

lying on the northeastern side. Intersection with the Navajo Springs

fault occurs in the vicinity of sec. 28, T. 20 N., R. 27 E. The Kirby

fault can be traced to the southeast into sec. 31, T. 20 N ., R. 28 E.

in the subsurface.

Salt Springs Fault. Recognition of the northeast striking Salt

Springs fault is based chiefly on the fact that helium-bearing gas under

relatively high pressure was encountered in the Crest 8 Santa Fe well

located in sec. 25, T. 20 N., R. 27 E., while the structurally higher

Crest 9 Santa Fe well, located in sec. 24 of the same township, is water

bearing. The Salt Springs fault is downthrown to the south with a dis­

placement of about 50 feet in the subsurface. Intersection of the Salt

Springs fault with the Kirby fault produces a fault wedge, the tip of 3 4

Figure 14. View Overlooking the Southeastern Portion of Pinta Dome.

This photograph was taken looking to the southeast from the Kerr-McGee 2 State well at Pinta Dome. Break in topography is probably the sur­ face expression of the southwestern portion of the Navajo Springs fault. 35 which appears to be broken by an unnamed fault of short length in sec.

26, T. 20 N., R. 27 E.

Other Features

Interpretation of subsurface data indicates that a structural depression with almost 50 feet of relief is present in the subsurface

near the crest of the Pinta Dome. This feature may be a collapse

structure formed by the solution of evaporites in the underlying Supai

Formation. The extent to which solution at depth has occurred in the

Pinta Domc-Navajo Springs area is a matter of speculation at the pres­

ent time. If such a phenomenon has taken place in sufficient amounts,

it may have been a contributing factor to some of the structural irreg­

ularities within the surrounding area.

Origin of Structures

The high angle, normal faulting that has occurred within the

study area closely approximates directions of prominent joint systems

and fracture patterns that have been described in other areas on the

Colorado Plateau (Kelley and Clinton, 1960). It is probable that these

joint and fracture patterns are controlled to some extent by ancient

fracture patterns in the basement rocks. The faults in the Pinta Dome-

Navajo Springs area may have been formed in response to more or less

vertical adjustments in the basement rocks along these preexisting

lines of weakness. The folds are probably the result of adjustment of

the sedimentary beds to this faulting. Some of the structural irreg­

ularities may be due to collapse following salt solution or to erosion

on top of the Coconino Sandstone. CHAPTER 4

SUMMARY OF PINTA DOME AND NAVAJO SPRINGS HELIUM FIELDS

History of Development

The discovery well was drilled on the Pinta structure by the

Kipling Petroleum Corporation in 1950. This well, formerly known as the

Kipling 1 Macie (now the Kerr-McGee 1 State), is located in sec„ 34, T.

20 N., R. 26 E. (Figure 15). The well struck a large flow of noncombus­ tib le gas from the Coconino Sandstone and was allowed to flow u n re stric t­ ed for a number of weeks. When it was later discovered that the gas had an exceptionally high helium content, the well was ordered shut-in by the

Bureau of Mines.

Six years later, in 1956, after several unsuccessful attempts had been made to drill and complete other wells, Kerr-McGee Corporation ac­ quired leases in the area and began to develop the field. In 1959, East­ ern Petroleum Company drilled several productive wells within the field.

Prior to unitization in January of 1968, there were nine producing wells

(six owned by Kerr-McGee and three by Eastern Petroleum) within the Pinta

Dome field (Table 1).

The discovery well on the Navajo Springs structure was drilled in

I960 by Eastern Petroleum Company and Crest Oil Company. This well, des­ ignated the Crest 2 Santa Fe, is located in sec. 33, T. 20 N., R. 27 E.

Helium-bearing gas was encountered in the upper portion of the Coconino

3 6 Figure 15. Discovery Well at the Pinta Dome Field.

Located in sec. 34, T. 20 N., R. 26 E., the Kerr-McGee 1 State (formerly the 1 Macie) was drilled by the Kipling Petroleum Corporation in 1950. 3 8

Table 1. Production Data for the Pinta Dome Helium Field, Apache County, Arizona, Prior to Unitization (January 1, 1968). Cumulative Well Year In itia l Production Owner Designation Completed Potential Raw Gas (MCFGPD) (MCF)

Kerr-McGee 4/4A State 1957/1967 420/42 48,510

Eastern Petroleum 1-28 State 1960 2,140 454,005

Kerr-McGec 1 Fee 1956 216 429,551

Kerr-McGee 3/3A State 1957/1966 140/584 128,668

Kerr-McGee 2 State 1956 2,400 1,022,535

Kerr-McGce 1 State 1956 2,500 . 346,058

Kerr-McGee 2 Fee 1957 10,000 489,783

Eastern Petroleum 1-2 State 1959 • 4,008 218,738

Eastern Petroleum 1-10 State 1960 150 43,372 3,181,220

Source: Arizona Oil and Gas Conservation Commission, 1968.

Tabic 2. Production Data for the Navajo Springs Helium Field, Apache County, Arizona, (January 1, 1968). Cumulative Well Year In itia l Production Owner Designation Completed Potential Raw Gas (MCFGPD) (MCF)

Kerr-McGee Barfoot State 1963 1,160 160,185

Eastern Petroleum 13 Santa Fe 1962 1,330 419,802 579,987

Source: Arizona Oil and Gas Conservation Commission, 1968 3 9

Sandstone, and the well was shut-in pending further development of the field.

At the present time, there arc two producing wells and eight shut-in wells within the Navajo Springs field. Of these wells, seven belong to Eastern Petroleum, two to Crest Oil and one to Kerr-McGee.

Production has thus far been limited to the two wells listed in Table 2.

Subsequent drilling activity has resulted in numerous productive and dry holes in the surrounding area. Of particular interest is the

Crest 8 Santa Fe well located in sec. 25, T. 20 N., R. 27 E. This well is not within the established limits of the Navajo Springs field, but is apparently related to another structure or isolated fault trap which exists in that area (Figure 9). This well contains gas with a helium content of about 9.8 percent, the highest helium content that has yet been found in the Pinta Dome-Navajo Springs area. Unfortunately, the

gas could not be commercially produced because of water in the Coconino

Sandstone. Therefore, the well was plugged and abandoned.

Structure

Pinta Dome Field

The producing structure of the Pinta Dome field is the northern

part of an asymmetric anticline that trends approximately northwest

across the southern portion of T. 20 N., R. 26 E." and the northern and

central portions of T. 19 N., R. 26 E. (Figure 9). Strata are more

steeply inclined on the northern and northeastern flanks of the struc­

ture. The anticline exhibits about 100 feet of relief in the subsur­

face. A northeasterly striking fault separates the Pinta Dome field 4 0 into two main productive elements. The field is bounded to the north- cast by the northwest striking Pinta Dome fault.

Navajo Springs Field

The main producing structure of the Navajo Springs field is a northwest trending anticline located in the southwestern portion of

T. 20 N., R. 27 E. and the northwestern portion of T. 19 N., R. 27 E.

(Figure 9). A subsidiary high is present northeast of the Navajo

Springs fold in the vicinity of secs. 27 and 28, T. 20 N., R. 27 E.

and is separated from the main fold by a northwest trending syncline.

Portions of the syncline are also productive.

The northern part of the Navajo Springs structure is terminat­

ed by the northeasterly striking Navajo Springs fault. The northwest

striking Kirby fault bounds the Navajo Springs field to the northeast.

Helium-Bearing Strata

Helium-bearing gases have been reported in several different

stratigraphic units within the general Pinta Dome-Navajo Springs area.

However, actual commercial production has thus far been limited to the

Coconino Sandstone reservoir. It should be noted that the Shinarump

Member and lower red member of the Chinle Formation may also serve as

reservoir rocks under proper conditions.

Reports of a deeper, nonflammable (helium?) gas sand situated

in the lower part of the Supai Formation have not been verified by gas

analysis or production testing within the Pinta Dome-Navajo Springs

area. Since an extremely limited number of wells have been drilled 4 1 through the Coconino Sandstone, it is impossible to evaluate the lower horizons at the present time.

Coconino Sandstone

The principal reservoir rock at Pinta Dome and Navajo Springs

is the Coconino Sandstone. It is a light gray to buff, fine- to medium- grained, mature, cross-bedded sandstone.

The effective porosity of the Coconino Sandstone reservoir some­

times reaches as much as 20 percent. Tables 3 and 4 summarize available

core analysis data for the Coconino Sandstone at Pinta Dome and Navajo

Springs. Permeability values are those measured in a horizontal direc­

tion parallel to the bedding planes of the reservoir rock. Although

v ertical permeability measurements were not taken, v ertical fractures

reportedly occur throughout the upper portion of the pay horizon. The

net effect of these fractures should be to increase the overall per­

meability of the reservoir rock and facilitate the migration of forma­

tion fluids.

Chinle Formation

Shinarump Member. Another gas-bearing horizon with possible

commercial production potential is the basal Shinarump Member of the

Chinle Formation. Although gas from this zone has never been commer­

cially produced at Pinta Dome or Navajo Springs, several wells have

encountered helium-bearing gas in this horizon. These wells, located

in secs. 14, 22 and 23, T. 19 N ., R. 26 E ., and sec. 31, T. 20 N .,

R. 28 E., report gas with a helium content ranging up to 8.5 percent. 4 2

Tabic 3. Summary of Core Analysis Data for the Pinta Dome Helium Field (Coconino Sandstone R eservoir), Apache County, Arizona. Number Average Well of Cored Effective Average Connate Designation* Samples Interval. Porosity Permeability Water (Feet) (Percent) (Md) (Percent)

East. 1-28 St. 36 942-978 13.8 86.2 39.9

East. 1-2 St. 47 987-1,044 15.0 161.5 60.7

East. 1-10 St. 26 947-1,000 14.6 231.1 63.3

*East. = Eastern Petroleum Company; St. = State.

Source: Kerr-McGce Corporation, 1968.

Table 4. Summary of Core Analysis Data for the Navajo Springs Helium Field (Coconino Sandstone Reservoir), Apache County, Arizona. Number Average Well of Cored Effective Average Connate Designation* Samples Interval Porosity Permeability Water (Feet) (Percent) (Md) (Percent)

East. 13S.F. 44 984-1,030 13.5 141.0 21.3

East. 14 S.F. 41 1,029-1,100 14.0 195.0 55.2

East. 17 S.F. 11 1,030-1,060 15.3 60.0 a

East. 31 S.F. 15 1,003-1,018 12.7 220.0 58.6

Crest 7 S.F. 12 1,044-1,056 14.4 167.0 a

*East. - Eastern Petroleum Company; S.F. = Santa Fe.

aData not reported.

Source: Lewis Engineering, Inc., 1964. 4 3

One well in sec. 14, T. 19 N,, R. 26 E, has been completed as a shut-in helium well in the Shinarump Member.

Although the Shinarump Member is believed to be a channel-type deposit over wide areas of northeastern Arizona (Cooley, 1959), it is present in the Pinta Dome-Navajo Springs area as a fairly persistent unit and can be traced across the area in the subsurface (Figures 10,

11, and 12). The lithology and thickness of the Shinarump Member vary greatly both on a regional and local scale. Unfortunately, core sam­ ples were not available for a more detailed study of this interval.

Lower Red Member. Deposits of lenticular sandstone and sandy mudstone have been encountered in d rillin g below the P etrified Forest

Member of the Chinle Formation and above the Shinarump Member. This interval has been referred to informally by Brown (1956) as the Chinle conglomerate. The sands are interpreted in this report as belonging to the lower red member of the Chinle Formation. This interval has been tested in several wells and, in one well, contains gas with a helium content of 7.4 percent. The Eastern 1-6 State well, located in sec. 6,

T. 19 N., R. 26 E., was completed in the sands of the lower red member as a shut-in helium well, but was later plugged and abandoned when it proved to be noncommercial. Further testing and development of this in­ terval may prove beneficial. There are no core analysis reports avail­ able for the lower red member. 4 4

Reservoir Pressure

The actual initial reservoir pressure at Pinta Dome is difficult to determine because the discovery well was not immediately shut-in upon completion. The average recorded shut-in pressure for the nine produc­ tive wells in the Pinta Dome field as of October 1, 1961 was 99.3 psig.

Prior to unitization, January 1, 1968, the average pressure had declined to 65.4 psig (Kerr-McGee Corporation, 1968).

An average reservoir pressure of 120 psia was calculated for the

Coconino Sandstone reservoir prior to commercial production at the Nav­ ajo Springs field (Lewis Engineering, Inc., 1964). Shut-in pressures for the productive wells in the Navajo Springs field show that by Jan­ uary 2, 1968 the average pressure had declined to about 90.0 psig. The average rate of decline for shut-in pressures of the productive wells indicates good continuity within each field. The fact that higher pres­ sures arc found in the Navajo Springs field indicates that two separate gas columns arc involved, and that there is no permeable communication between the two.

Gas-Water Contact

Established gas-water contacts for the Pinta Dome field indi­ cate that the gas-water interface is tilted to the northeast at a rate of 50 to 80 feet per mile (Figure 16, in pocket). Masters (1960) rec­ ognized this phenomenon and interpreted it as the result of a drag on

the gas-water interface caused by the slow northeastward flow of water

through the Coconino Sandstone. 4 5

Within the Navajo Springs field, the gas-water interface is tilted to the north or northeast at an average rate of 40 feet per mile.

Quality of the Gas

The gas produced from the Pinta Dome and Navajo Springs struc­ tures is of sim ilar quality. Table 5 compares the resu lts of some of the gas analyses that have been run on gas samples from each field . An outstanding feature of the gas, aside from its helium content, is the lack of appreciable amounts of hydrocarbon gases. In general, the aver­ age composition is 90 percent nitrogen, 8 to 9 percent helium, and 1 percent carbon dioxide. Argon and methane are commonly found in propor­ tions averaging less than one percent, and traces of ethane, propane, oxygen, and hydrogen may also be present.

Such a mixture of predominantly inert gases produces an incom­ bustible gas with no heating value. Consequently, the gas would be of little or no market value if it were not for its rich helium content.

Production

Two privately owned and operated helium extraction plants have been erected at Navajo, Arizona, to process the raw gas produced from the surrounding area. The Kcrr-McGcc plant has been in operation since

1961, while a new plant, constructed by the Arizona Helium Corporation, will soon be in operation. The plants are capable of processing sev­ eral million cubic feet of raw gas per day. Presently, most of the helium produced at Navajo is being shipped either as compressed gas or

liquid to consumers on the West Coast. Table 5. Some Typical Gas Analyses from the Coconino Sandstone Reservoir, Well Designation Pinta Dome Field Navajo Springs Field Kerr-McGee Kerr-McGee Eastern Eastern Crest Crest Constituent 1 Fee 2 Fee 1-2 State 1-10 State 2 Santa Fe 7 Santa Fe

(Percent)

Methane trace 0.1 0.1 trace 0.2 0.0

Nitrogen 89.4 90.0 89.9 90.0 89.9 90.6

Oxygen 0.1 trace trace trace 0.1 0.0

Carbon dioxide 0.9 0.8 0.8 0.8 0.9 0.8

Argon 0.6 0.5 0.6 0.5 0.7 0.5

Helium 9.0 8.3 8.2 8.5 8.2 8.0

100.0 99.7 99.6 99.8 100.0 99.9 trace = less than 0.05 percent.

Source: Kerr-McGee Corporation, 1968; and Munnerlyn and M iller, 1963 4 7

The first official commercial production of helium from the Pin­ ts Dome field was in 1961. Production from the Navajo Springs field did not begin until 1964. A summary of the cumulative production of raw gas prior to January 1, 1968 is given in Tables 1 and 2 for each productive well at the Pinta Dome and Navajo Springs fields.

Unitization

As helium-bearing gas represents a valuable natural resource of

Arizona, certain steps in conservation must be taken to insure that max­ imum recovery is obtained and waste is minimized. As provided by Ari­ zona statute, the Oil and Gas Conservation Commission has the authority to establish drilling units for each oil or gas pool discovered within the state.

Perhaps one of the greatest contributions to modern conservation is the management and production of oil and/or gas reservoirs through fieldwide unitization. Such a plan usually involves:

1. A pooling of all working and royalty interests within the

area to be unitized.

2. Calculation of participation factors for each separately

owned lease based on proportional ownership of acreage in

the unit or the amount of oil and/or gas under any one

lease as compared to the total amount of oil and/or gas

under the united acreage.

3. Management and production of the field as a unit operation

utilizing the best engineering and production techniques under the rules and regulations as set forth by state

regulatory agencies.

The Navajo Springs field was unitized prior to commercial pro­ duction in 1964. The Eastern Petroleum Company was designated as the operator of the Navajo Springs Coconino Sand Gas Pool Unit.

A fieldwidc unitization program has recently been approved for the Pinta Dome Coconino Sand Gas Pool Unit. The plan was activated at

Pinta Dome on January 1, 1968. Since that time, the field has been managed and operated by the Kcrr-McGcc Corporation.

Reserves

The size of the helium reserves at the Pinta Dome and Navajo

Springs fields has long been a subject of wide speculation. Early in the history of the Pinta Dome field it was rumored that the discovery probably represented one of the largest known helium occurrences in the world. A published report by Kcrr-McGcc (Masters, 1960) placed the

Pinta field reserves at that time as around 8.8 billion cubic feet of raw gas in place. Taking a recovery factor of 85 percent and an aver­ age helium content of 8 percent, it was concluded that the net recov­ erable amount of raw gas in place at Pinta Dome was 7.5 billion cubic feet, which represented 0.6 billion cubic feet of helium. Thus, the

Pinta Dome field was not considered to be a large reserve of helium gas. However, because of the relatively high percentage of helium found in the raw gas, the area probably represented the greatest ac­ cumulation of helium per acre-foot of reservoir volume. 4 9

An engineering study (Lewis Engineering, Inc., 1964) of the

Coconino Sandstone reservoir at the Navajo Springs field indicated re­ serves in excess of 4.7 billion cubic feet of raw gas in place for that field. Based on a gas recovery factor of 85 percent, and an average helium content of 8 percent, the net recoverable amount of raw gas in place before production began was probably about 4 billion cubic feet which would represent a little more than 0.3 billion cubic feet of helium.

It should be stressed that the reserve estimations given above do not show the amount of helium reserves at the present time. They reflect the approximate amount of proven reserves before commercial production began in either field. In addition, the reserve figures are those for the Coconino Sandstone reservoir, and do not show the potential of other helium-bearing strata in the area. CHAPTER 5

ORIGIN OF TERRESTRIAL HELIUM

Since the discovery of helium in uranium-bearing minerals by

Ramsay in 1895, and in natural gas by Cady and McFarland in 1905, its origin has been a subject of considerable discussion. Basically, there are two principal theories: (1) that helium is primordial and is de­ rived from sources deep within the earth, and (2) that helium is pro­ duced by the process of radioactive decay. Generally speaking, the theory that ascribes helium to radioactive decay seems to be the most widely accepted at the present time.

Helium is given off in the form of alpha p articles during the

spontaneous disintegration of certain radioactive elements. Almost

a ll natural alpha em itters arc found among the heavy elements in the

decay series of uranium2385 uranium235> and thorium232 (Faul, 1954).

Since the disintegration of each of these radioactive substances pro­

ceeds at a definite rate, the amount of helium so produced can be cal­

culated for a given amount of radioactive material. Table 6 shows the

accepted rate of production of helium by uranium and thorium in equi­

librium with their products. Utilizing this data, Rogers (1921) cal­

culated that from 282-1060 m illion cubic feet of helium are generated

per year from radioactive substances normally distributed throughout

the rocks of the earth’s crust. It seems logical to conclude, there­

fore, that much, if not all, of the helium found in sedimentary rocks

5 0 5 1

Table 6. Rate of Production of Helium from Uranium and Thorium,

Radioactive Alpha particles Helium produced substance per gm./sec. per gm./yr.

(cu. mm)

Uranium 2.37 x 104 2.75 x 10~5

Uranium (in equilibrium with all its products) 9.7 x 1CT 11.0 x lO-^

Thorium (in equilibrium with all its products) 2.7 x HT 3.1 x 10-3

Radium (in equilibrium with emanation, radium . . A, and radium C 13.6 x 101U 158

Source: Rogers, 1921 5 2 can be accounted for by radioactive processes. However, the reason for accumulations of helium-rich gas in particular areas is largely unre­

solved. Rogers (1921) felt that is was necessary to postulate a local deposit of the radioactive elements in each helium-rich district.

Morrison and Beard (1949) concluded that special concentrations of the radioactive elements were not necessary, and that occurrences of helium-

rich gas can be accounted for simply by the accumulation of gases from

the disintegration of normal rock types. Recent studies in the Texas

Panhandle (Pierce, Mytton, and Gott, 1955) revealed that uranium may be

redistributed and concentrated in rocks through which petroleum has mi­

grated or accumulated.

Assuming that the ultimate source of helium in helium-rich gas

is the spontaneous disintegration of radioactive substances, the ques­

tion arises as to the immediate source of these substances in the Pinta

Dome-Navajo Springs area. Basically only two possibilities seem to

exist: (1) that the helium is being produced at depth by the disinte­

gration of radioactive substances within the crystalline basement rocks,

or (2) that the helium is being produced from local deposits of radio­

active substances in other formations.

The Coconino Sandstone is not known to contain radioactive

material. However, significant deposits of uranium have been found in

certain areas of the Colorado Plateau in the lower part of the Chinle

Formation (Isachsen and Evensen, 1955). Many of these deposits are

found in the Shinarump Member.

Examination of available gamma-ray logs from the Pinta Dome-

Nava jo Springs area shows definite gamma-ray anomalies throughout the 5 3 lower part of the Chinle Formation and part of the Moenkopi Formation.

Correlation with formation tops, as derived from electric log analysis, indicates that the most prominent gamma-ray anomalies occur in the lower part of the Shinarump and Petrified Forest Members of the Chinle Forma­ tion. No gamma-ray anomalies were found below the base of the Moenkopi

Formation.

The indication that radioactive source material is present in the lower part of the Chinle Formation may have an important bearing on the origin of the helium-bearing gases found in the Pinta Dome-Navajo

Springs area. This, in itself, cannot be considered conclusive evidence but is presented as' a p o ssib ility which should not be overlooked. Among the chief objections to such -a theory is that the main reservoir horizon at Pinta Dome and Navajo Springs lies below the proposed radioactive source. Thus, i t would appear that any helium generated in the lower part of the Chinle Formation would have to migrate downward in order to accumulate in the Coconino Sandstone. Obviously, it would be difficult to account for a gas behaving in such a manner. Perhaps, it is more reasonable to suppose that the source beds have been brought into di­ rect contact with the Coconino Sandstone by the vertical displacement of beds along faults. The displacement involved would only have to be about 125 feet. Many of the faults within the area have displacements of this magnitude.

On the other hand, the alternate basement theory cannot be to­

tally disregarded. The lack of information on the basement rocks in

the Pinta Dome-Navajo Springs area leaves the subject open to specula­

tion. It would seem unlikely, however, that appreciable quantities of 5 4 helium-rich gases could have migrated upward through several thousand feet of sediments overlying the basement rocks. The situation is fur­ ther complicated by the fact that almost a thousand feet of these sed­ iments consist of rela tiv e ly impermeable evaporitic material and red bed deposits.

The specific origin of the helium-rich gas in the Pinta Dome-

Navajo Springs area cannot be ascertained at the present time. Exhaus­ tive qualitative and quantitative studies would be necessary to estab­

lish a link between the proposed radioactive source and the actual gases which arc present at Pinta Dome and Navajo Springs. However, a solution to the problem of the specific origin of the helium-rich gas at Pinta

Dome and Navajo Springs would be of value as far as future exploration efforts arc concerned. CHAPTER 6

RESULTS AND CONCLUSIONS

This study of the subsurface stratigraphy and structure of the

Pinta Dome-Navajo Springs area suggests the following results and con­ clusions.

The general stratigraphy of the Pinta Dome-Navajo Springs area is relatively simple, and formation characteristics do not vary greatly from those found in other locations in central Apache County. Formation members can be traced across the study area in the subsurface by anal­ ysis of wire-line log characteristics.

Structures in the Pinta Dome-Navajo Springs area appear to have been formed in response to nearly vertical adjustments within the base­ ment rocks. The movements at depth may have taken place along old lines of weakness. Principal deformation probably occurred during the Lara- mide Revolution, as local folds are not reflected in Tertiary and young­ er sediments.

It is possible that structures in the Pinta Dome-Navajo Springs area have been modified to some extent by the differential solution of evaporites in the upper part of the Supai Formation. Such a phenomena may be indicated in the Pinta Dome area by a structural sag that appears near the crest of Pinta Dome. This feature may be a collapse structure caused by solution at depth.

5 5 56

The Finta Dome and Navajo Springs fields exhibit structural con­ trol in the subsurface. A northeastward hydrodynamic gradient in the

Coconino Sandstone maintains a tilted gas-water contact in both fields.

The gas productive limits of each field are determined by fault bound­ aries to the north and northeast, and by edgewater contacts in all oth­ er directions.

The results of the present study were inconclusive insofar as determining the ultimate source of the helium-bearing gases found in the Finta Dome-Navajo Springs area. However, a radiogenic origin for the helium is strongly implied by the fact that gamma-ray anomalies, indicating radioactive material, are found in the lower part of the

Shinarump and Petrified Forest Members of the Chinle Formation. It is suggested that the helium has been produced within these stratigraphic units by radioactive decay, and has subsequently migrated into suitable

traps where it is presently found. APPENDIX A

TOWNSHIP PLATS SHOWING LOCATIONS OF DRILL HOLES IN THE PINTA DOME-NAVAJO SPRINGS AREA

57 T. 19 N ., R. 26 E

Location Designation Perm it No

SW NE 1 Eastern 2 Reese 348 SW NW 1 Eastern 1 Reese 157 NE SW 2 Eastern 1-2 State 81 m SE 4 Kerr-McGee 3 State 37 NE NE 4 Kerr-McGee 3A State 349 SW NE 5 Ram 1-5 Hortenstine 196 SE NE 6 Eastern 1-6 State 78 SW NE 9 Ram 1-9 Hortenstine 178 NE NE 10 Eastern 1-10 State 80 NE SW 12 Sierra 2 State 123 NE SE 12 Duval 2 Strat SE NW 13 Linehan 1-13 Spurlock 135 S% SW 14 Ram 1-14 State 167 SW SW 14 Ram 1A-14 S tate 177 SE SE 15 Eli 1 Hortenstine 352 SW NE 16 Sierra 4 State 1 2 1 SW NE 17 Walker 1 Lansdale 320 SW NE 20 McCaughey 1 Sunland S tate 262 NW SE 21 Fletcher 1-21 Spurlock 214 SW SW 22 Duval 12 Strat NW SE 22 Apache 1-22 State 346 NE SE 22 Teil 1 Kruglich-Fletcher 143 NW SW 23 Linehan 1-23 Spurlock 148 SW NE 23 • Apache 1 Spurlock 318 SE NW 26 Hallett 2 State 465 NE NW 27 Linehan 2-27 Spurlock 149 SE NE 28 Hallett 1 State (10602) 451 NE SW 28 Wilkinson 1 Sunland State 6 8 NE SW 28 Wilkinson 2 Sunland State 87 NW NE 36 Hallett 1 State (10603) 449 NE NE 36 Duval 1A Strat 58

• 78 349 + > -I9 G "348 (j 4 5 ]L • H 37

81

170 j c) __ 1 n 1 , 1 JLu . — 1 i 2 3 ‘ A

320 -F 121 135 o l 7 __ 2 < i '-f. o . i f s i 5 —1 1 4 1 3

352 >

__ 2 G2 318 1 Q 2 9 1 9 9 1 o t Z Z J • 2 4 &-214 f 8 • 'A~ i

K91

3 o 2 9 9 Q 9 *7 465 A O 451 Z / ^ 2 0 2 5 4 j.67 68

•* aHA 3 1 3 3 3 2 3 4 3 5 3 6 —

Explanation:

Producing helium well Dry hole, abandoned

Shut-in helium well Temporarily abandoned

-$j$* Abandoned producer A Mineral strat test

T. 19 N . , R. 26 E. T. 19 N., R 27 E

Location Designation Perm it No

SE NW 1 Eastern 34 Santa Fe 273 SW NE 3 Crest 3 Santa Fe 124 SW NW 4 Eastern 17 Santa Fe 236 SE NW 5 Eastern 14 Santa Fe 206 SW NE 6 Crest 7 Santa Fe 204 SE NW 8 Eli 2 Santa Fe 216 NE NE 8 Eastern 29 Santa Fe 250 NE SW 9 Eastern 3 Santa Fe 109 NE NE 9 Eli 1 Santa Fe 185 NW NW 10 Duval 28A Strat SW NE 12 E astern 19 Santa Fe 229 SW NW 14 Kerr-McGee 1 Santa Fe 402 SW SW 19 Duval 30 S tra t SW NE 22 Duval 15 Strat C E% 23 E astern 20 Santa Fe 230 NE NE 24 Kerr-McGee 11 Santa Fe 413 SW SW 28 Duval 39 Strat 59

206 124 ^204 ' 3 —— j - / ) 5

*A 3 185 A "^-21 - f 1229 7 ( — c) . 1 ft i / t> u . i i 12 •Abb

$ o — %7 %g 402 V, o . >15 — • 14 13 — —

413 _ — A

— 1g _ on L f30 r A

3o 9 2 Q o 9 A 2 O Z 7 — Z 0 25 —

• A - -

— 3 1 2 ___ 3 33 - 34 35 36 —

Explanation:

Shut-in helium well A Mineral strat test

Dry hole, abandoned

T. 19 N ., R. 27 E T. 20 N ., R. 26 E

Location Designation Perm it

NW NW 9 Linehan 1-9 Spurlock 147 SW SW 13 Wilson 1 Harris 119 SW SE 21 Linehan 1-21 Spurlock 136 SE SW 23 Eastern 1 Reese 296 NE SE 27 Kerr-McGee 1 Reese 64 SE SE 28 Eastern 1-28 State 8 8 NW SE 30 Sierra 3 State 1 2 2 SE NE 31 Linehan 1-31 Spurlock 137 SW NE 32 Kerr-McGee 4 State 38 NE SE 32 Kerr-McGee 4A State 378 SW SE 33 Kerr-McGee 1 Fee 1 0 SW SW 34 Kerr-McGee 1 State NW SE 34 Kerr-McGee 2 State 36 N% NW 35 Kerr-McGee 2 Fee 39 NW NE 35 Kerr-McGee 3 Fee 142 SW NE 36 Kerr-McGee 5 State 91 60

— _ c ... . 1 7 , i £ 4 J 1 ■ z l

4 7

c 1 ,A ^ , 9 , > c ■ 5 ‘ JL1u. 1 Z

1 7 1 A . 1 i 4 , \ 3 1 8 : • 1 1 O X5 ■

1 9 >

__

o A O o 9 3 __ 9 1 1 9 z V * Z 1 Z Z 2 4 296

f 36

, o A g 0 Q 9 5 2 ■ z O ' Z 7 ■ 2 6 2 • j "

6 4 6 8 *

• • 3 9 " ^ 2 " k — 4 . T 1 4 9 1 3 1 - 3 2 /. . 1 o c 3,6 r * J J ' 3 36 — Jo 137

•^r f e l l —

Explanation:

Producing helium well Abandoned producer

~^r Shut-in helium well Dry hole, abandoned

T. 20 N., R. 26 E. T. 20 N ., R. 27 E

Location Designation P erm it No

SE m 3 Eastern 28 Santa Fe 276 SE NE 5 E astern 22 Santa. Fe 268 SE m 7 Eastern 2 Santa Fe 108 NE SW 11 Eastern 12 Santa Fe 188 NE SW 13 Eastern 18 Santa Fe 237 SW NE 15 Eastern 15 Santa Fe 209 NE SW 19 Crest 1 Santa Fe 1 1 2 NE SW 21 Eastern 36 Santa Fe 264 NW SE 22 Kerr-McGce 12 Santa Fe 414 NW SW 23 Kerr-McGee 10 Santa Fe 405 NE SW 24 Crest 9 Santa Fe 203 N& 24 Eastern 24 Santa Fe 284 SE NW 25 C rest 8 Santa Fe 134 SE NW 25 Apache 1 Santa Fe Crest 353 SW NE 26 Crest 11 Santa Fe 182 NE SW 26 Eastern 25 Santa Fe 289 NE SW 26 Crest 5 Santa Fe 129 NE SW 26 Crest 5-A Santa Fe 151 NW NW 26 Duval 21 Strat NE SW 27 Eastern 35 Santa Fe 263 NE SW 28 Eastern 32 Santa Fe 258 N% SE 29 Eastern 31 Santa Fe 255 NW SE 30 E astern 33 Santa Fe 259 NE SW 31 Eastern 13 Santa Fe 194 NE SW 32 Kerr-McGee Barfoot State 238 NE SW 33 Crest 2 Santa Fe 1 1 0 SE NW 34 Eastern 37 Santa Fe 269 SW NE 34 Brown 1 Santa Fe 140 NE NE 35 C rest 6 Santa Fe 130 61

^276 4 . / j . .. (- 5 __ 266 A1- 2 1

106

JL4 . A- ' 188

209 1 O 7 1 g 1 0 . l 1 4 ,1 5 T= A-13 237

-

269 .130 - f ri40 - 3 1 2 , Q/,4 J 5 J AO 1 : 9 4 238 110 ; * *

Explanation:

Producing helium well A Mineral strat test *4" Shut-in helium well —o- Water w ell Dry h o le, abandoned Show helium, abandoned

T. 20 N., R. 27 E. APPENDIX B

WELL DATA FOR THE PINTA DOME-NAVAJO SPRINGS AREA

62 T. 19 N , , R. 26 E ______Stratigraphic Tops ______' Surface Lower T o tal Designation Elevation Datum* Red Shinarump • Moenkopi Coconino Depth

Eastern 2 Reese 5727 KB 788 865 8 8 8 1013 1067 Eastern 1 Reese 5732 KB 813 867 899 1033 1077 Eastern 1-2 State 5740 KB 716 811 846 ‘ 973 1054 Kerr-McGee 3 State 5777 KB 743 856 872 1 0 1 2 1198 Kerr-McGee 3A State 5765 G 719 814 838 965 1005 Ram 1-5 Hortenstine 5672 G 667 771 784 928 948 Eastern 1-6 State 5663 KB 672 780 801 950 1013 Ram 1-9 Hortenstine 5726 G 732 805 850 971 993 Eastern 1-10 State 5743 KB 727 817 845 975 1035 Sierra 2 State 5756 G 823 877 902 1034 1 1 0 0 Duval 2 Strat 5735 G 907 947 1072 1594 Linehan 1-13 Spurlock 5788 G 854 901 934 1065. 1083 Ram 1-14 State 5760 DF 737 775 801 997 1004 Ram 1A-14 S tate 5776 G ' 812 Eli 1 Hortenstine 5725 G 821 879 909 969 986 S ie rra 4 S tate 5609 G 862 1016 Walker 1 Lansdale 5553 G 564 693 732 857 865 McCaughey 1 Sunland St 5571 G 634 689 715 854 862 Fletcher 1-21 Spurlock 5651 G 672 746 776 917 926 Apache 1-22 State 5725 G 687 779 804 936 1701 Teil 1 Kruglich-Fletcher 5729 G 752 760 Duval 12 Strat 5670 G 730 802 951 1583 Linehan 1-23 Spurlock 5773 DF . 985 990 Apache 1 Spurlock 5836 G 853 929 966 1099 1 1 0 0 Hallett 2 State Linehan 2-27 Spurlock 5715 G 694 757 786 925 957

o\ u> T» 19 N., R. 26 E.--Continued Stratigraphic Tops Surface Lower T o tal Designation E lev atio n Da turn* Red Shinarump - Moenkopi Coconino Depth

Hallett 1 State (10602) Wilkinson 1 Sunland St 5597 G 638 692 739 8 8 6 1040 Wilkinson 2 Sunland St 5597 G 638 701 739 885 960 Hallett 1 State (10603) Duval 1A Strat 5982 G 1360 2005

G = Ground KB = Kelley Bushing DF = Derrick.Floor

CTi .o T. 19 N . , R. 27 E Stratigraphic Tops Surface Lower T o tal Designation E levation Datum* Red Shinarump Moenkopi Coconino Depth

E astern 34 Santa Fe 5976 G 1217 1247 1304 1408 1440 Crest 3 Santa Fe 5893 G 1084 1 1 1 1 1 1 2 1 1266 1280 Eastern 17 Santa Fe 5775 G 030 8 6 8 905 1023 1057 Eastern 14 Santa Fe 5801 G 826 8 8 6 903 1030 1 1 0 0 Crest 7 Santa Fe 5806 G 831 898 911 1048 1060 Eli 2 Santa Fe 5838 G 921 1 0 1 2 1 0 2 0 1127 1138 Eastern 29 Santa Fe 5821 G 890 926 945 1093 1 1 0 1 Eastern 3 Santa Fe 5890 KB 934 1 0 1 0 1070 1168 2932 Eli 1 Santa Fe 5870 G 1003 1053 1194 1208 Duval 28A Strat 5880 G 1023 1040 1176 1894 Eastern 19 Santa Fe 5965 G 1217 1266 1301 1402 1422 Kerr-McGee 1 Santa Fe 6052 KB 1184 1253 1318 1387 1417 Duval 30 Strat 6034 KB 1130 1207 1230 1354 1890 Duval 15 Strat 6140 G 1265 1303 1453 1981 Eastern 20 Santa Fe 6160 G 1329 1396 1433 1543 1557 Kerr-McGee 11 Santa Fe 6111 G 1236 1275 1292 1423 1455 Duval 39 Strat 6115 KB 1248 1333 1348 1471 2 0 0 1

* G = Ground KB = Kelley Bushing T. 20 N., R. 26 E Stratigraphic Tops Surface Lower Total Designation E lev atio n Da turn* Red Shinarump Moenkopi Coconino Depth

Linehan 1-9 Spurlock 5745 G 903 1030 1059 1194 1230 Wilson 1 Harris 5632 G 870 940 992 1099 1127 Linehan 1-21 Spurlock 5600 KB 829 889 922 1056 1082 Eastern 1 Reese 5602 G 814 922 933 1067 1098 Kerr-McGee 1 Reese 5627 KB 733 842 857 979 1052 Eastern 1-28 State 5702 KB 690 771 807 935 1091 Sierra 3 State 5616 G 742 813 843 989 1036 Linehan 1-31 Spurlock 5532 G 575 647 672 809 860 Kerr-McGee 4 State 5575 KB 581 652 674 828 836 Kerr-McGee 4A State • 5555 G 550 639 655 793 834 Kerr-McGee 1 Fee 5743 G 730 787 812 956 2517 Kerr-McGee 1 State 5780 KB 781 850 900 1027 1520 Kerr-McGee 2 State 5778 DF 741 839 870 994 2502 Kerr-McGee 2 Fee 5671 KB 697 794 822 952 1006 Kerr-McGee 3 Fee 5640 KB 811 911 939 1070 1086 Kerr-McGee 5 State 5653 KB 920 952 930 1180 1 2 0 0

G = Ground KB = Kelley Bushing DF = Derrick Floor

C\ON T. 20 N . . R. 27 E ______Stratigraphic Tops______Surface Lower T otal Designation Elevation Da turn* Red Shinarump Moenkopi Coconino Depth

Eastern 28 Santa Fe 5732 G 830 896 916 1023 1037 E astern 22 Santa Fe 5710 G 787 845 853 988 1 0 2 2 Eastern 2 Santa Fe 5776 KB 908 978 1005 1129 1240 Eastern 12 Santa Fe 5892 G 1098 1166 1179 1287 1305 Eastern 18 Santa Fe 5833 G 1106 1206 1229 1335 1353 Eastern 15 Santa Fe 5743 G 1040 1090 1114 1223 1244 Crest 1 Santa Fe 5659 KB 950 1023 1072 1195 1226 Eastern 36 Santa Fe 5705 G 1015 1069 1237 1285 Kerr-McGee 12 Santa Fe 5737 G 1033 1118 1129 1249 1283 Kerr-KcGee 10 Santa Fe 5754 G 1305 1330 Crest 9 Santa Fe 5779 G 1297 1290 Eastern 24 Santa Fe 5792 G 1141 1198 1208 1306 ' 1340 C rest 8 Santa Fe 5789 G 1154 1242 1262 1351 1372 Apache 1 Santa Fe Crest 1286 Crest 11 Santa Fe 5764 G 1 2 0 2 1265 1288 1381 1391 Eastern 25 Santa Fe 5752 G 1 0 0 1 1084 1104 1204 1223 Crest 5 Santa Fe 5754 G 940 1013 1028 1140 1180 C rest 5-A Santa Fe 5757 G 1126 1135 Duval 21 Strat 5760 G 1105 1325 1978 Eastern 35 Santa Fe 5750 G 1053 1072 Eastern 32 Santa Fe 5754 G 851 924 945 1090 1133 Eastern 31 Santa Fe 5680 G 773 837 862 992 1049 Eastern 33 Santa Fe 5660 G 1019 1080 1093 1233 1265 Eastern 13 Santa Fe 5740 G 771 820 830 965 980 Kerr-McGee Barfoot State 5726 KB 776 835 847 985 1087

o\ T. 20 N ., R. 27 E. --Continued Stratigraphic Tops Surface Lower T otal Designation E levation Datum* Red Shinarump . Moenkopi Coconino Depth

Crest 2 Santa Fe 5761 KB 854 916 948 1062 1140 Eastern 37 Santa Fe 5842 G 969 1 0 0 1 1 0 2 0 1172 1 2 0 2 Brown 1 Santa Fe 5861 G 980 1058 1117 1 2 1 1 1214 C rest 6 Santa Fe 5798 G 1005 1072 1128 1 2 2 0 1231

G = Ground KB = Kelley Bushing APPENDIX C

CHANGES IN DESIGNATION OF WELLS AND CORRECTED ELEVATIONS IN THE PINTA DOME-NAVAJO SPRINGS AREA

Original Information Changes and Corrections

Designation E levation* Designation E levatioi

Kipling 1 Macie 5220 G Kerr-McGee 1 State 5780 KB

Kipling 2 Macie . 5743 G Kerr-McGee 1 Fee 5743 G

Apache 3 Macie 5778 DF Kerr-McGee 2 State 5778 DF

Kerr-McGec 5 State 5667 KB Kerr-McGee 5 State 5653 KB

Kerr-McGee Barfoot 5752 KB Kerr-McGee Barfoot 5726 KB S tate S ta te

Brown 1 Santa Fe 5846 DF Brown 1 Santa Fe 5861 G

Crest 7 Santa Fe 5840 G Crest 7 Santa Fe 5806 G

* G = Ground KB = Kelley Bushing DF = Derrick Floor

69 LIST OF REFERENCES

Akers, J. P ., 1961, The geology of the central part of Apache County, Arizona (a preliminary report): Ariz. Geol. Soc. Digest, v. 4, p. 49-57.

______, 1964, Geology and ground water in the central part of Apache County, Arizona: U. S. Geol. Survey Water-Supply Paper 1771, 101 p.

Akers, J. P ., Cooley, M. E., and Repenning, C. A., 1958, Moenkopi and Chinle Formations of Black Mesa and adjacent areas: N. Mex. Geol. Soc. Guidebook of the Black Mesa Basin, North­ eastern Arizona, p. 88-94.

Arizona Oil and Gas Conservation Commission, 1968, Well logs and pro­ duction data, Phoenix, Arizona.

Bahr, C. W., 1962, The Holbrook anticline, Navajo County, Arizona: N. Mex. Geol. Soc. Guidebook of the Mogollon Rim Region, Eastcentral Arizona, p. 118-122.

Brown, S. C., 1956, Petroleum and natural gas potentialities: Mineral Resources Navajo-Hopi Indian Reservations, Arizona-Utah, v. 1, p. 64-72.

Brown, S. C., and Lauth, R. E ., 1958, O il and gas p o t e n t i a l i t i e s of northern Arizona: N. Mex. Geol. Soc. Guidebook of the Black Mesa Basin, Northeastern Arizona, p. 153-160.

Cooley, M. E., 1957, Geology of the Chinle Formation in the upper L ittle Colorado drainage area, Arizona and New Mexico: unpub­ lished M.S. thesis. The Univ. of A riz., Tucson, 317 p.

______, 1959, Triassic stratigraphy in the state line region of west-central New Mexico and east-central Arizona: N. Mex. Geol. Soc. Guidebook of West-Central New Mexico, p. 66-73.

Dean, J. W., 1960, Helium potential of the Navajo-Chambers area, Apache County, Arizona: Interstate Oil Compact Commission Bull., v. 2, p. 33-48.

70 71

LIST OF REFERENCES--Continued

Dobbin, C. E., 1935, Geology of natural gases rich in helium, nitrogen, carbon dioxide and hydrogen sulphide: in Geology of Natural Gas, The American Assoc, of Petroleum Geologists, Tulsa, Oklahoma, p. 1053-72.

Paul, H., 1954, ed., Nuclear geology; a symposium on nuclear phenomena in the earth sciences: John Wiley and Sons, Inc., New York, New York, 414 p.

Gerrard, T. A., 1964, Environmental studies of the Fort Apache Member, Supai Formation (Permian), east-central Arizona: unpublished Ph.D. dissertation, The Univ. of Ariz., Tucson, 187 p.

Gregory, H. E., 1917, Geology of the Navajo country: U. S. Geol. Survey P ro f. Paper 93, 161 p.

’______, 1950, Geology and geography of the Zion Park region, Utah and Arizona: U. S. Geol. Survey Prof. Paper 220, 200 p.

Harshbarger, J. W., Repenning, C. A., and Irwin, J. H., 1957, Strati­ graphy of the uppermost Triassic and the Jurassic rocks of the Navajo country: U. S. Geol. Survey Prof. Paper 291, 74 p.

Huddle, J. W., and Dobrovolny, E., 1945, Late Paleozoic stratigraphy of central and northeastern Arizona: U. S. Geol. Survey Oil and Gas Inv. P relim in ary Chart 10.

Isachsen, Y. W., and Evensen, C. G., 1955, Geology of uranium deposits of the Shinarump and Chinle Formations on the Colorado Plateau: U. S. Geol. Survey Prof. Paper 300, p. 263-280.

Kelley, V. C., 1958, Tectonics of the Black Mesa basin region of Arizona: N. Mex. Geol. Soc. Guidebook of the Black Mesa Basin, Northeastern Arizona, p. 137-144.

Kelley, V. C., and Clinton, N. J ., 1960, Fracture systems and tectonic elements of the Colorado Plateau: Univ. of N. Mex. Pub. in Geology, no. 6 , 81 p.

Kerr-McGce Corporation, 1968, Core analysis data, pressure data and gas an a ly sis d ata, Oklahoma C ity, Oklahoma.

Lance, J. F ., 1954, Age of the Bidahochi Formation, Arizona: Geol. Soc. America B ull., v. 65, p. 1276. 72

LIST OF REFERENCES--Continued

Lewis Engineering, Inc., 1964, Engineering study of the Coconino Sand­ stone reservoir, Navajo Springs field, Apache County, Arizona: f i l e re p o rt, E astern Petroleum Company, Carmi, I l l i n o i s .

McCann, F. T., 1938, Ancient erosion surface in the Gallup-Zuni area, New Mexico: Am. Jour. Sci., V. 36, p. 260-278.

McKee, E. D., 1934, The Coconino Sandstone—its history and origin: Carnegie I n s t. Wash. Pub. 440, p. 77-115.

, 1951, Sedimentary basins of Arizona and adjoining areas: Geol. Soc. America B ull., v. 62, p. 481-506.

, 1954, Stratigraphy and history of the Moenkopi Formation of Triassic age: Geol. Soc. America Mem. 61, 133 p.

. Masters, J. A., 1960, Pinta Dome helium gas reserves: Interstate Oil Compact Commission B ull., v. 2, p. 30-32.

Morrison, P., and Beard, D. B., 1949, He^ and the origin of terrestrial helium: Physical Review, v. 75, p. 1332-1333.

Munnerlyn, R. D., and Miller, R. D., 1963, Helium-bearing natural gases of the United States, U. S. Bur. of Mines Bull. 617, 93 p.

Peirce, H. W., 1962, Stratigraphy of the De Chelly Sandstone of Arizona and Utah: unpublished Ph.D. dissertation, The Univ. of A r iz ., Tucson, 206 p.

Peirce, H. W., and Gerrard, T. A., 1966, Evaporite deposits of the Permian Holbrook basin, Arizona: Northern Ohio Geol. Soc. Second Symposium on S a lt, v. 1, p. 1-10.

Pierce, A. P ., Mytton, J. W., and Gott, G. B., 1955, Radioactive ele­ ments and their daughter products in the Texas Panhandle and other oil and gas fields in the United States: U. S. Geol. Survey Prof. Paper 300, p. 527-532.

Read, C. B., and Wanek, A. A ., 1961, S tratig rap h y o f outcropping Permian rocks in parts of northeastern Arizona and adjacent areas: U. S. Geol. Survey Prof. Paper 374-H, p. 1-10.

Rock-Color Chart Committee, 1948, Rock-color chart: National Research Council, Washington, D. C. 73

LIST OF REFERENCES— Continued

Rogers, G. S., 1921, Helium-bearing natural gas: U. S. Geol. Survey P rof. Paper 121, 113 p.

Stewart J. II., 1957, Proposed nomenclature of part of upper Triassic strata in southeastern Utah: Am. Assoc. Petroleum Geologists Bull., v. 41, p. 441-463.

Stirton R. A., 1936, A new beaver from the Pliocene of Arizona with notes on the species of Dipoides: Jour. Mammology, v. 17, p. 279-281.

Winters , S. S., 1963, Supai Formation (Permian) of eastern Arizona: Geol. Soc. America Mem. 89, 99 p. 1 fie c e s ' V\ ipSC-VoA ,2 Subsurface Elevati o +4900 0 9 4 -+ -4-4500 -4-4600 -4-4700 4800 -+ -4-4400 +• 5000 - Hortenstine 1-5 WEST 'K B Ram 4 ------KerrMcGee - Fee I -%m4r

I U E I IT DM - NVJ SRNS RS SCIN - B ( AT- S ) EST EAST-W ( B' B - SECTION CROSS NAVAJO SPRINGS DOME - PINTA FIGURE II - - - Section A-A q - Sae State I State 3-A er -MGe Kerr~ McGee KerrMcGee -

^ - 4 i. m — a * ' - - - - ^ ------

5/omi.- * Kerr-McGee 2 State 2 * rdcn Helium WellProducing hti HeliumShut-in Well bnoe Producer Abandoned r Hole,AbandonedDry

. i m % Kerr- MCGee Fee 2 4 mi- % T ^cp

T?ci rc T?cs rasc Chinle Formation Triassic Kerr ~McGee Fee3 Petrified Forest Member oe Rd MemberLower Red hnrm Member Shinarump

EXPLANATION . i m g / H Ti m ^mm ^mh T?mw Kerr -MCQee State 5 *+*■ rasc MoenkopiFormationTriassic Holbrook Member Moqui Member Wupatki Member

- i m g / ' • 13 Fe Santa Eastern *

c ema Coconino PermianSandstone Pc etcl cl 1 Scale Verticalin.= 100 ft. %>mU oiotl cl 4in. =Horizontal Imi. Scale afo State Barfoot Kerr-MCQee *

Imi. — — 2 Santa Fe Santa 2 Section C-C Crest * , Imi. 7 at Fe Santa 37 R. E. Dunlap Eastern Prepared by EAST ■H 1969 B

- 0 0 7 4 4

- 0 0 5 4 4 4-4900- - 0 0 6 4 4 4-4800- 4-5000-1 44400-* usrae lvto, Fee Elevation, Subsurface ncw cn £ XI

R 26 E R 27 E

EXPLANATION

Alluvium

T

20 Silt, sand , and gravel N

NAVAJO Upper Member Calcareous, sandstone, siltstone and mudstone

Lower Member Sandstone, mudstone, and claystone interbedded with volcanic ash

Bidahochi Formation

UNCONFORM ITY

O Petrified Forest Member CO CO Sandstone, siltstone, mudstone < and claystone E cr f- Chinle Formation

T

T 19 ? ^ ' . z r s 1 N SCALE MILES

Prepared by R. E. Dunlop 1969

N V * w

After J p Akers, 19 64

FIGURE 4 GEOLOGIC MAP OF THE PINTA DOME-NAVAJO SPRINGS AREA SmiMERGER MILiirtiyriiii SI RlEllIfi lORPORHID^

ELECTRICAL LOG r LATERCL03 I - t - COMPANY KERR MC SEE _ locotion of Well i- OIL INDUSTRIES NW sE “ T * - • -f '1 sEw . 34-20N-26E - l - ! WELL ~1—' t J— I _ STATE ; - _ , i - --j--- - ■ t .;■* T j I ;---- r^- — f - r i f — —k—»-']! - zinn— — r' t t "t— t " + * — , ^ ~ 'p ^ 'rT "Th FIELD WILDCAT ES LL ♦* • *4* •“* ♦-« -f—•• | —- ^ • \* • ■* *■ • • -4 -*■—A t<| • W • 4— ►- *• *4i « *-• r - ' 1 * |t V ' a l l or (ML CRN LL") T 4 : | f tri LOCATION SEC 34-2QN-26E ...... r I ;• Elevolion' D.F.i ■ ...... ^ f *• ‘ • * ■ I *" Jf- * t? “ Hh I ** 7 * T K.I.I *■ j^t* ^ * i"‘V '“V Ii*| f" ‘' ' *‘ ' 4 '*■ r 1, • • * •* • • I A lU . I I- - - - tf -jl !»! | COUNTY ^ C H E _ _ ::.t I Ut i- * . #u :yi. .- t . . U lt : : r 4------f — STATE . ARIZONA __ FILING No. .. S ill: I l l s § j:):ki] } - r r rt \'J** i; 1 ^ 1*” V 4r| ■ h.* • -rt -1. t —> 4— j- t n H V 'if - *r ’ t j 'I f" ~ r • • • • ♦ • 4 j F " ’ ‘ A ‘ * f ‘ F 'i ^ RUN No ______| T • • ♦ * Do*. !iO .-5 -5 6 l. 4 ; First Peoamy • t~ - * t * lost Pending ' ' •' Iffl .,. Fee* Meosured ||| , k ' # t Cig Schluf* ^69 ^ ------______a |C»g Driller ?86 Dep,wi Receded $00“ @ " - CJoo j Ojoo 0400 )900 Bottom Dr Her Depth Dotum JfM F = : " A* vd Not GEL CMEm^ALT gel:::_____- - L .... I . . . | . . . . -. . -L . . . W • ; • ------f • • 33 8 - . I . - j ____j_. •9 «^ • A.0 a fl. -. i| —— -- — - - ■ — — ViKOlify | ^4 I ■ . . • . i * • i * . f , 4 | ‘ | 4 ' • • • j . • •- J • • •■• t T* * j * t — t-

f « - s ? ‘ 65»: Area. Springs Dome-Navajo Pinta the BhT .| 9 Hi Re> ... ! . : pH Wtf loss - (.c JO i i r " Temp F 89 e— ♦-—— ^ — *-■ ♦- — —• - -»-—►- f-■ — a- •*- * * «- — — ' 1 *■ ♦- * ---— • * ' • * i *" ' * j ~ *" ' t * \J 4 « ♦ . ♦ -A- • -f t— " " ' k u 6 i/4" ; r ~ • d d | - ^ I • I • 1 * f A- • i * ; ‘ • • • • t • • t socas. "M A A -* f A - • A- A - — s i r Ill 4 ■ ■ r i 1 - i -4 « • | * • A- A - h . 4 ♦ , J — &c:i@'a . . F . ^ a- 4 • • — • —4 ♦- « * ♦ —* A* a | • - -t * ~y T ’ i f ::j :^ckNl TltY&ARM !7%ARM: a#::::. i 1 i- . . 1 . . . . . ! . . j I r • i * ' ■

_ i • ! From Log trie-Gamma-Ray 6. Figure Elec Typical A Ecncif 1 1 6 9 ZJ

R 26 E. R 27 E

+ 4725 —,

+ 470 0 / / z

5745 G +4551 57 76 KB + 46471

+4605 EXPLANATION

5743 G ^ Producing Helium Well +4525 +4520 \ 5833 G + 4498 Shut-in Helium Well

+4533 + 4500 Abandoned Producer Show Helium, Abandoned ______+ 4 4 7 5 ------T - c + Dry Hole, Abandoned "V 5659 KB- +4450 ^^5705G<^ "Y" 5754G Z Temporarily Abandoned Well —— + 4464 ^+4 468 5779 G. -----_^= = +4425_-.^Xi & Mineral Strat Test, Abandoned -o Water Well 5789 G s Shinarump + 4436 5680G| + 4427 5702 KB 6 4688 +4664 + 4 7 6 7 - 5757 G —\ ------^ ,+4631 a P —— Approximate Location of Fault 5575 KB J 15798G ^ D Down thrown Side +4747/ + 4719 565 3 K 5861 G +4578 5532 G +4473 + 4650 U Upthrown Side 5778 OF 5842G + 4723 + 4670 — + 4700— Structural Contour on Coconino Sandstone 5555 G 1+4784 "^-5740 G -\-^ 5 7 5 6 KB ST" 5761 KB +4775, \ +474,\ X +4699^ + 4 7 0 0 -.,. Inferred Contour on Coconino Sandstone

5700 G Surface Elevation + 4800 5801 G 5806 G 5976 G + 4744 I \ +4758 + 4771 5775 G +4627 \ ' G Ground KB Kelly Bushing DF Derrick Floor

5743 KB + 4 7 6 7 Elevation on Top of Coconino Sandstone + 4768 A 5838G 5870G" 5726 Gr LL / I 7 I l +4676 N +4755'/ A------A' Line of Cross Section \5 9 6 5 G 5890 KB + 4722 Contour Interval = 25 Feet

SCALE A - 5788G + +46967 + 5 6 0 9 6 ' ± A 70-X ^ 6 0 5 2 KB I '/2 0 1/2 I MILES / / + 4747 j ^ ^ ^ y + 4 6 6 5 -6-^ A 5760 OF - 5725 G 5+4763 " + 4756 A 5571G 5725 G 0 5836 G / 6140 G Prepared by T +4717 + 4789, + 4737 , + 4687 5651 G 5573 OF R. E. Dunlap + 4788 1969 + 4719 y* 6045KB 7 ^ 57|5GT , + 4691 > f + 4 790 N

5597 + 4711 6165 KB + 4644 5982 G

FIGURE 9 STRUCTURAL CONTOUR MAP ON THE TOP OF THE COCONINO SANDSTONE £ o Subsurface Eleva c (-44500 44600 0 6 4 -4 -44700 -+4800 +4900 -+ + 5000 I U E 0 IT DOME (NORTH-SOUTH PINTA CROSS SECTION) A-A1 FIGURE 10 - Hortenstine 1-9 SOUTH A'|<- Ram ^ Aadnd Producer Abandoned -^4 j i Su-n eim Well Helium Shut-in -jji- Dry /^mi- e, le o H Abandoned

------Kerr - McGee State 3 k 5 ------c Ptiid oet ebr ^mh "Res Petrified Forest Member ^cp c Lwr e Mme Ttmm Lower Red Member *cl

hnrm Mme "Rmw Shinarump Member / mi.5/8 ------c^i B-B1 i ect^ S Kerr- MCGee - State 3-A k 5 ------

Wupatki Member Moqui Member Holbrook Member I Zg mi.

etcl cl Iin.= 100ft. Vertical Scale Horizontal in. I= 4 Scalemi. — — -8 State 1-28 Eastern *

I mi. . . Dunlap E. R. rprd byPrepared 1969 ------iea 8 StoltenbergLinehan 8 -1 Spurlock1-21 NORTH 5^ A

FIGURE 12 Subsurface Elevation, Feet L+4400 -+4500 —1-4600 r + 5000 -+4700 -+4800 +4900 0 9 4 -+ A A O PIG COS ETO C- (NORTH-SOUTHNAVAJO 1) SECTION CROSS -C SPRINGS C P.3 SOUTH Eastern c'K- Santa Fe < ) Dry-<{)- Hole, Abandoned bnoe ProducerAbandoned %mi.

17 Santa Fe Eastern

is hnrm Member Shinarump Tics Member Red Lower ^cl 7/fi

mi. ------m Moqui Member ^mm eto 8-B'Section m Wupatki Member ^mw 2 at Fe Santa Crest * ------

I mi. Horizontal Scale 4in. = I 4in. mi. Horizontal Scale etcl cl Iin. =100 ft. Scale Vertical ------2 at Fe Santa 32 Eastern Sfc + ------

I mi . . Dunlap E. R. Prepared by 1969 6 Santa Fe 36 NORTH Eastern ■^1 C

n e ? x \

R 26 E R 27 E

EXPLANATION T 20 N Producing Helium Well * Shut-in Helium Wei 1 A * Abandoned Producer > Show Helium, Abandoned 4 Dry Hole, Abandoned A Mineral Strat Test, Abandoned -O Water Well

2 - -__ Approximate Location of Fault U D Downthrown Side (J Upthrown Side

+4700------— Gas-Water Contour ^ ■ 25-^ , Gas Pay Contour 4 4694 Elevation of Gas-Water Contact est Estimated (47') Thickness of Gas Pay Gas -Water Contour Interval =10 Feet Gas Pay Contour Interval = 25 Feet

SCALE

I '/2 0 1^2 I MILES

T 19 Prepared by N R E. Dunlap 1969

N k

FIGURE 16 GAS-WATER CONTACT AND ISOPACH OF GAS PAY OF THE COCONINO SANDSTONE RESERVOIR