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Information to Users RELATIVE AGES AND THE GEOLOGIC EVOLUTION OF MARTIAN TERRAIN UNITS (MARS, CRATERS). Item Type text; Dissertation-Reproduction (electronic) Authors BARLOW, NADINE GAIL. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by 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. Download date 06/10/2021 23:02:22 Link to Item http://hdl.handle.net/10150/184013 INFORMATION TO USERS While the most advanced technology has been used to photograph and reproduce this manuscript, the quality of the reproduction is heavily dependent upon the quality of the material submitted. For example: • Manuscript pages may have indistinct print. In such cases, the best available copy has been filmed. o Manuscripts may not always be complete. In such cases, a note will indicate that it is not possible to obtain missing pages. • Copyrighted material may have been removed from the manuscript. In such cases, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, and charts) are photographed by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each oversize page is also filmed as one exposure and is available, for an additional charge, as a standard 35mm slide or as a 17"x 23" black and white photographic print. Most photographs reproduce acceptably on positive microfilm or microfiche but lack the clarity on xerographic copies made from the microfilm. For an additional charge, 35mm slides of 6"x 9" black and white photographic prints are available for any photographs or illustrations that cannot be reproduced satisfactorily by xerography. 8711625 Ba rlow, Nadine Gail RELATIVE AGES AND THE GEOLOGIC EVOLUTION OF MARTIAN TERRAIN UNITS The University of Arizona PH.D. 1987 University Microfilms International 300 N. Zeeb Road, Ann Arbor, MI48106 PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark_-I_. 1. Glossy photographs or pages v"" 2. Colored illustrations, paper or print /' 3. Photographs with dark background..L.. 4. Illustrations are poor copy ____ 5. Pages with black marks, not original copy --L 6. Print shows through as there is t~xt on both sides of page ___ 7. Indistinct, broken or small print on several pages ___ 8. Print exceeds margin requirements __ 9. Tightly bound copy with print lost in spine ___ 10. Computer printout pages with indistinct print ___ 11. Page(s) lacking when material received, and not available from school or author. 12. Page(s) seem to be missing in numbering only as text follows. 13. Two pages numbered . Text follows. 14. Curling and wrinkled pages __ 15. Dissertation contains pages with print at a slant, filmed as received / 16. Other-------------------------------------- University Microfilms International RELATIVE AGES AND THE GEOLOGIC EVOLUTION OF MARTIAN TERRAIN UNITS by Nadine Gail Barlow A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 8 7 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Final Examination Committee, we certify that we have read the dissertation prepared by ~N~a~d~i~n~e~G~a~i~l~B~a~r~l~o~"~T ___________________________ entitled Relative Ages and the Geologic Eyol11tiop of Martian Terrain Units and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy ;~A/ Date ito ,J<>'/k.>.."-'7 (lg7 Date I Il,b Lq, ~LlJ l' ~,J Date I ] Qf: C(1~ 4to -J .. ___,., J181 Date ~~~ (6 uqPp /qzr1- Date Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copy of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. Dissertation Director STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requiraments 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 dissertation are allowable without special permission, provided that accurate acknowledgment of sources 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 or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. ACKNOWLEDGMENTS Many people have been influential in the pursuit and . completion of this dissertation. I thank my advisor, Robert Strom, for the initial suggestion of this project and financial support for the past 4.5 years. My other committee members, Victor Baker, Robert Butler, Clement Chase, Michaei Drake, and William Hubbard, provided many useful suggestions for improvements and clarifications to the text. Stephen Drew, James Pesavento, Joseph Willis, Sandra Miles, and the late William Beckett provided much encouragement earlier in my career, and I thank them for the many car.eer-advancing opportunities they offered me. The support of friends Lisa Ramirez, Kathleen Wallis, Anne Volckmann, Linda Berens, Virginia Gulick, Steve Pearce, and the rest of my fellow graduate students (past and present) is greatly appreciated. I thank Richard Binzel for information on nonparametric statistics, John Spencer for assistance with computer-related problems, Mary Ellen Byers for secretarial assistance, Gail Georgenson for help in the Space Imagery Center, Karen Denomy for her excellent work on the maps, and Theresa Schemenauer for the photographic work. Robert Marcialis provided many constructive comments for improving the text, as well as much emotional support before 1ii iv and during the actual writin~of the dissertation--I look forward to the continuation of the special relationship which has developed between us. Finally, I thank my parents, Nathan and Marcella Barlow, for their constant support, both financial and otherwise--I dedicate this work to them. This research was funded under NASA Grant NSG7146. TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS. • • . • • • vi LIST OF TABLES • • . · . x ABSTRACT •• . • xi 1. INTRODUCTION . 1 Spacecraft Encounters ••••••••• 1 Absolute Versus Relative Chronologies. 5 2. SUMMARY OF EXISTING MARTIAN RELATIVE CHRONOLOGIES. • 13 Previous Chronologies. • • • • • • • • • • • •• 13 Problems Inherent in Existing Chronologies • .~ • 18 3. REVISED MARTIAN CHRONOLOGY: METHOD AND RESULTS ••• 23 Crater Size/Frequency Distribution Plotting Techniques • • • • • • • • •• ••••• 23 Background for Present Chronology •••••• 0 •• 29 Data Gathering and Analysis. • • • • • • • • • • 33 Results. • • • • • • • • • • • • • • • • • • 41 Constraints on Major Geologic Events • • • • • • 77 4. CONSTRAINTS ON MARTIAN THERMAL EVOLUTIONARY MODELS • 86 Data Constraining Thermal Models • . • 86 Proposed Thermal Models. • • • • • 97 5. SUMMARY •• . • • .104 APPENDIX • . • • • .111 The Chi-Square Test. • • • • • • • • .111 The Wald-Wolfowitz Runs Test • • •• 114 REFERENCES • • • • • • • • • • • • . •• 118 v LIST OF ILLUSTRATIONS Figure Page la. Cumulative Size/Frequency Distribution Plots of Heavily Cratered Terrain (Uplands) and Plains.. 25 lb. Relative Size/Frequency Distribution Plots of Heavily Cratered Terrain (Uplands) and Plains.. 26 2. stylized Relative Plot, showing the appearance of curves with slope indices -2, -3, and -4. •• 28 3. Relative Size/Frequency Distribution Plots of Heavily Cratered and Lightly Cratered Terrain on the moon( C), MerCury("), and Mars(d) • •• 30 4. Map showing the spatial extent of the 23 gen­ eralized martian geologic units used in this . study. .. 36 Sa. Example of a crater displaying a rampart ejecta blanket. .. 40 5b. Example of a crater displaying a ballistic, or lunar-like ejecta pattern. • • • • • • • • • •• 40 5c. Example of a well-preserved crater which displays no observable ejecta blanket • • • • • ••• 40 5d. Example of a partially buried crater . 40 6. Relative Size/Frequency Distribution Plots of the Martian Uplands (Upl), Fractured Uplands (FrU), Ridged Plains (RP1), and Mottled Plains t Mot). • • • • • • • • • • • • • • • • • • • •• 42 7. Relative Size/Frequency Distribution Plots of the Martian Intercrater Plains (ICP), Exhumed Uplands (ExU), and Cratered and Fractured Plains ( CFP). • • • 0 • • • • • • • • • • • • • • • •• 43 8. Relative Size/Frequency Distribution Plots of the Martian Knobby Terrain (Kby), Outflow Channels (Chn), and Chaotic Terrain (Cht) • • • • • • • • 44 vi vii LIST OF ILLUSTRATIONS--Continued 9. Relative Size/Frequency Distribution Plots of the Martian Dissected Uplands (DsU), Mountainous Terrain (Mtn), Plains (Pls), and Volcanic Shields (VSh). • • • 8 • • • • • • • • • • • • • • • •• 45 10. Relative Size/Frequency Distribution Plots of the Martian Fretted Terrain (Frt), Equatorial Layered Deposits (ELD), Basin Floor Deposits (BFD), and Volcanic Plains (Vol) ••••••
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