Stratigraphical Analysis of Triassic and Lower Jurassic Rocks in Northeastern Arizona Item Type text; Thesis-Reproduction (electronic) Authors Ashouri, Ali-Reza Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the Antevs Library, Department of Geosciences, and the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author or the department. Download date 03/10/2021 23:14:58 Link to Item http://hdl.handle.net/10150/231216 STRATIGRAPHICAL ANALYSIS OF TRIASSIC AND LOWER JURASSIC ROCKS IN NORTHEASTERN ARIZONA by Ali -Reza Ashouri cT -. Q h r1'., >' I '-OOits ry..,J VCr,.f"h-: iCE$ UN1vER 1-0,ILU1_liA A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCE In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 8 0 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: A4c-4") APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: RICHARD F. WILSON bate Professor of Geoscience ACKNOWLEDGMENTS I wish to express my heart -felt thanks to the members ofmy committee; to Dr. H. W. Peirce who providedme with useful comments and discussion during the preparation of this thesis, andto Dr. T. L. Smiley who also aided my thesis development, and helped directme through my course of study. I cannot adequately write or say my gratitude tomy advisor Dr. R. F. Wilson for all the help and guidance he has offeredme dur- ing my academic studies and development of this thesisto its conclu- sion. His scholarship and personal understanding imparted tome the skills of a geologist, and the human appreciation of theprocess of mentor ship. I also wish to thank Dr. M. Shafiqullah for his very useful discussion. Finally, an appreciated thanks to my friend Jeff Zauderer for his various comments. 111 TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS . vi ABSTRACT . viii CHAPTER 1 INTRODUCTION . 1 General Statement . 1 Location of Study Area . 1 Methods of Study . 5 2 REVIEW OF THE STUDIED FORMATION . 11 Moenkopi Formation . 11 Chinle Formation . 12 Church Rock Member of Chinle Formation and Rock Point Member of Wingate Sandstone . 14 Glen Canyon Group . 14 General Statement . 14 Wingate Sandstone . 15 Moenave Formation . 16 Kayenta Formation 17 Navajo Sandstone . 18 3 MAP INTERPRETATION . 20 General Statement . 20 Moenkopi Formation Interval . 20 Chinle Formation Interval . 25 Glen Canyon Group Interval . 33 General Statement . 33 Isopach Map of Total Glen Canyon Group Interval . 33 Wingate Sandstone . 36 Moenave Formation . 42 Kayenta Formation 48 Navajo Sandstone . 5 3 4 CONCLUSION . 58 iv V TABLE OF CONTENTS (Continued) Page APPENDIX A: INDEX TO LOCATION OF CONTROL POINTS AND SOURCE OF DATA . 61 LIST OF REFERENCES . 71 LIST OF ILLUSTRATIONS Figure Page 3 1. Index Map of Study Area . 2. Sketch Showing Well Numbering System Used in theStudy Area 6 3. Chart Showing Triassic and Early JurassicFormations and Lesser Subdivision in the Northeastern Arizona . 7 . 21 4. Index Map of Moenkopi Formation . 22 5. Isopach Map of Moenkopi Formation . 6. Shale /Sand Ratio Map of Moenkopi Formation 24 7. Cross Sections of Moenkopi Formation in pocket 8. Index Map of Chinle Formation . 28 . 29 9. Isopach Map of Chinle Formation . 31 10. Triangle Facies Map of Chinle Formation . 11. Cross Sections of Chinle Formation in pocket 12. Cross Sections of Glen Canyon Group . in pocket 13. Index Map of Glen Canyon Group . 34 14. Isopach Map of Glen Canyon Group . 35 . 37 15. Index Map of Wingate Sandstone . 16. Isopach Map of Wingate Sandstone 38 17. Sand /Shale Ratio Map of Wingate Sandstone 41 18. Index Map of Moenave Formation 44 19. Isopach Map of Moenave Formation . 45 20. Sand /Shale Ratio Map of Moenave Formation 47 vi vii LIST OF ILLUSTRATIONS (Continued) Figure Page 21. Index Map of Kayenta Formation . 49 22. Isopach Map of Kayenta Formation . 50 23. Sand /Shale Ratio Map of Kayenta Formation 52 24. Index Map of Navajo Sandstone . 54 25. Isopach Map of Navajo Sandstone . 55 26. Sand /Shale Ratio Map of Navajo Sandstone . 57 ABSTRACT A review of all available surface and subsurface data on Triassic and Lower Jurassic rocks in northeastern Arizona has revealed the following information. The Moenkopi Formation, the Chinle Formation, and the Glen Canyon Group of Traissic and Early Jurassic age are present throughout most of the study area. These units form a sequence of con- tinental and transitional marine origin that shows notable vertical and lateral facies changes. The Moenkopi Formation thickening west and northwestward with a maximum thickness of 134 meters. The unit comprises sandstone and shale, and shows more shaley facies westward. The Chinle Formation shows minimum thickness to the north and thickens toward east and south with a maximum thickness toward west. This unit dominantly consists of sandy shale, but contains more sand- stone westward and north westward. The unit contains some limestone in north and northern region. The Chinle Formation is overlain by the Glen Canyon Group, which in ascending order comprises the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. The Wingate Sandstone shows its maximum thickness in the central and southcentral region of the study area and thins west and eastward. This unit mainly comprises sand- stone, particularly in its upper part. viii ix The Moenave Formation displays its zero thickness,in the eastern region and shows its maximum thickness, 198 meters,in the west - central part. The unit mainly consist of sandstone. The Kayenta Formation attains its greatest thickness, 204 meters, in the southwestern part of the region and thins east and northward. This formation contains high percentages of sandstone. Within the area of this study, the Navajo Sandstone is the thickest formation in the Glen Canyon Group. This unit almost entirely consist of sandstone pinches out toward the south and east, and displays its maximum thickness,300 meters, northward. CHAPTER 1 INTRODUCTION General Statement The Moenkopi and Chinle Formations of Traissic Age and the Glen Canyon Group of Late Triassic and Early Jurassic Age are present in most of northeastern Arizona, either in the surface or subsurface. Both surface and subsurface data were used in this study for a review and analysis of Triassic and lower Jurassic rocks. The study area mainly is the Black Mesa basin and adjacent areas in northeastern Ar- izona. For more detail, the whole stratigraphic section studied is divided into three sequences, in ascending order:Moenkopi Formation, Chinle Formation, and the Glen Canyon Group. Location of Study Area The study area mainly comprises Black Mesa and adjacent areas in northeastern Arizona. This area is approximately 85,000 kilometers square, and limited by 35° to 37° 15'latitude, and 108° 30 to 112° longitude. The area is a part of the Colorado Plateau. The Colorado Pla- teau is an elevated structural platform of flat-lying sedimentary strata comprising an area of 338,000 square kiometers in Utah, Colorado, Arizona, and New Mexico. The structure within the Colorado Plateau is 1 2 relatively simple. Monoclines, faulted monoclines ,and normal faults fold and break the strata along generallynorth or northwest - trending belts. Broad uplifts, including the Zuni,Defiance, Monument, Circle Cliffs, and Uncompahgre uplifts and the SanRafael Swell, elevate the strata; even larger basins,including the San Juan, Black Mesa,Uinta, and Piceance basins, depress the strata(Stewart, Poole and Wilson 1972a) . For the most part, the sedimentary stratathat mantle the Col- orado Plateau are relatively thinformations of wide extent. The pla- teau throughout much of Paleozoicand Early Mesozoic time was a broad shelf area (craton) lying to the eastof the great Cordilleran geocline of western Utah, Nevada and California. Many of the formations thicken in the western part of the plateau into ortoward this geocline. Al- though locally thickened masses of strata weredeposited in deep basins, no persistent geosynclinesexisted on the plateau (Stewart et al.1972a). The index map (Fig. 1) is derivedfrom Geohydrologic Data (Part III 1964). Most data, either logs or stratigraphicsections, have been taken from thisreference. In this book, all logs and stra- tigraphic sections are arranged inthe numerical order of the 18 admin- istrative districts of the Bureauof Indian Affairs and in accordance with 15- minute quadrangles withineach district. No data are included in this report from districts13 and 15, which are outside the study area. The quadrangle location number indicates theposition of a well or stratigraphic section within a15- minute quandrangle and consists of 111 110' 109' nrMltnqs 3r WalerWMtlrr f MON 111UyA.AryJUANCO CO NAVAJO r..urw,earwrnQtpn---f I-litt1 - - - --T îi 3.'--- vein .....4Y 15 INveinDIAN< REST°i RVAl1ONo/OP Croon Rent 7 WhorlWeltsiP-- Thoreau _ f,nn)e1a11 0ece' wall utn ArxrndrvyEXPLANATIONIwneoubrxrndorr of,-- Indianowl 73number Afloirs ofd's/rrCl d'slr'N ' fh.th, nffliA IrulamAu Ser1nC! 1rrnrnul muds Number nl 15.I Nschool0 TPmewls a>Iedrvgle Figure 1.