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Cambrian Highland Peak Formation, Eastern Nevada UNLV Retrospective Theses & Dissertations 1-1-2002 Analysis of cyclic shallow-water carbonates: Cambrian Highland Peak Formation, eastern Nevada Robyn Allyn Howley University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/rtds Repository Citation Howley, Robyn Allyn, "Analysis of cyclic shallow-water carbonates: Cambrian Highland Peak Formation, eastern Nevada" (2002). UNLV Retrospective Theses & Dissertations. 1365. http://dx.doi.org/10.25669/fty4-hqj1 This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Retrospective Theses & Dissertations by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. ProOuest Information and Learning 300 North Zeeb Road, Ann Arbor. Ml 48106-1346 USA 800-521-0600 UMI" Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ANALYSIS OF CYCLIC SHALLOVV-VVATER CARBONATES: CAMBRIAN HIGHLAND PEAK FORMATION. EASTERN NEVADA bv Robyn A. Howley Bachelor o f Science Salem State College, Salem, M A 1999 A thesis submitted in partial fulfillment o f the requirements for the Master of Science Degree Geoscience Department College of Sciences Graduate College University of Nevada, Las Vegas August 2002 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 1411183 Copyright 2002 by Howley, Robyn Allyn All rights reserved. UMI UMI Microform 1411183 Copyright 2003 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Copyright by Robyn A. Howley 2002 A ll Rights Reserv'ed Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Thesis Approval UNTV The Graduate College University of Nevada, Las Vegas May 17 ..20. 02 The Thesis prepared by Robyn A. Howley Entitled Analysis of Cyclic Shallow-Water Carbonates: Cambrian Highland Peak Formation. Eastern Nevada__________________________________________________ is approved in partial fulfillment of the requirements for the degree of Master of Science Examination Committee Chair Member Dean o f the Graduate College Examination Committee Member ■ _____________ Examination Comméiée Member Gradiïate College Faculty Representative 1017-53 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Analysis of Cyclic Shallow-Water Carbonates: Cambrian Highland Peak Formation, Eastern Nevada by Robyn A. Howley Dr. Margaret N. (Peg) Rees Professor o f Geology University o f Nevada, Las Vegas Several methods o f analysis were used to test the robustness o f sea level signals recorded in Middle to lower Upper Cambrian shallow-water carbonate rocks in the southwestern United States and to refine stratigraphie correlation o f this interval. Embedded Markov chain and cycle architectural analysis define the high-frequency accommodation signal, whereas cycle grouping pattern and facies proportions analysis reveals low-frequency sequence stratigraphie accommodation changes. Gamma analysis and Fischer plots were unsuccessful in deciphering the signature o f high or low frequency signals. Six low-frequency accommodation events are present in the Middle to lower Upper Cambrian Highland Peak Formation. Each sequence is bounded by minimum accommodation zones that are correlative across the shallow-water carbonate platform and thus, record platform-wide relative sea level change. Two o f these minimum accommodation zones record eustasy. Ill Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ABSTRACT..................................................................................................................................iii LIST OF FIGURES.....................................................................................................................vi LIST OF PLATES.................................................................................................................... viii ACKNOWLEDGMENTS.......................................................................................................... ix CHAPTER 1 INTRODUCTION................................................................................................1 Geologic Setting .......................................................................................................................3 Stratigraphy .............................................................................................................................. 6 Methods ................................................................................................................................... 10 CHAPTER 2 CYCLE CARBONATE SEDIMENTATION................................................ 12 Carbonate Sedimentation ...................................................................................................... 12 Causes o f Cyclic Sedimentation .......................................................................................... 15 CHAPTER 3 LITHOLOGIC ANALYSIS AND FACIES DELINEATION....................24 Burrow Mottled Lithotope ................................................................................................... 24 Siliciclastic Lithotope ........................................................................................................... 34 Peloidal Packstone Lithotope ............................................................................................... 40 Oolite Lithotope .................................................................................................................... 48 Laminite Lithotope ................................................................................................................ 55 Boundstone Lithotope ...........................................................................................................64 Silty Intraclastic Lithotope ....................................................................................................77 Facies Interpretations ............................................................................................................ SO Summary ................................................................................................................................ 84 CHAPTER 4 HIGH FREQUENCY SIGNAL.......................................................................86 Embedded Markov Chain Analysis ....................................................................................87 Cycle Architecture ................................................................................................................ 95 Gamma Analysis ..................................................................................................................106 Summary.............................................................................................................................119 IV Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER 5 LOW FREQUENCY SEA LEVEL SIGNAL..............................................120 Cycle Grouping Analysis .................................................................................................... 121 Fischer Plots .......................................................................................................................... 131 Facies Proportions Analysis ................................................................................................144 Summary................................................................................................................................153
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