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River Channel Patterns: a Geographic Analysis University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1973 River channel patterns: A geographic analysis Anthony L. Murgatroyd The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Murgatroyd, Anthony L., "River channel patterns: A geographic analysis" (1973). Graduate Student Theses, Dissertations, & Professional Papers. 7746. https://scholarworks.umt.edu/etd/7746 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. RIVER CHANNEL PATTERNS: A GEOGRAPHIC ANALYSIS By Anthony L. Murgatroyd B.A. (Hons.), London University, 1972 Presented in partial fulfillm ent of the requirements for the degree of Master of Arts UNIVERSITY OF MONTANA 1973 Approved by: ' — /7 Chairman, Board of Examiners* D^^,*'Grad^>^ School . 2 .... Date V Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: EP38547 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT D H M rtatio n UMI EP38547 Published by ProQuest LLC (2013). Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code ProQuest ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 -1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS The author wishes to express his appreciation to Mr. Colin Thorn for chairing the thesis committee. Dr. Harold Bockemuehl and Dr. Robert Curry also served on the committee. All offered constructive criticism and advice. Special thanks go to Mr. Darshan S. Kang for his valuable assistance in the in itia l stages. The author is indebted to his parents and to his future wife, Susan, without whose encouragement and sacrifice this research would not have been possible. n Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Page ACKNOWLEDGMENTS ........................................................................................................ ii LIST OF TABLES........................................................................................................ v LIST OF FIGURES.............................................................................................................vi CHAPTER I. INTRODUCTION ............................................................................... 1 Purpose of This Study ........................................................................... 1 Format of the Study ............................................................................... 3 CHAPTER I I . DEFINITION AND CLASSIFICATION OF RIVER CHANNEL PATTERNS ........................................................................................... 5 Inadequacies of Previous Classificatory Schemes ....................... 5 Descriptive Indexes............................................................................... 9 Comprehensive Scheme for Channel PatternDescription . 13 CHAPTER I I I . REVIEW OF THE LITERATURE...........................................................15 Direction of Current Research.......................................................... 15 Relative Importance of Factors Controlling Channel P a t t e r n .....................................................................................................17 Dependent, Semi-Dependent and Independent Variables.... 23 Climatic Base of River Channel Patterns........................................ 27 CHAPTER IV. THE STUDY............................................................................................ 33 Research Methods ................................................................................... 33 Spatial and Quantitative Analysis of the Relationship Between Channel Pattern and Climate.......................................... 38 CHAPTER V. RIVER CHANNEL PATTERNS AND CLIMATIC CHANGE ....................... 51 Evidence of Channel Pattern Change .............................................. 51 Theory of Evolution of River Channel Pattern Adjustment in Response to Increasing Aridity ......................................... 56 CHAPTER VI. CONCLUSIONS ................................................................................... 60 APPENDIX I ..................................................................................................................... 64 111 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Page APPENDIX I I ..................................................................................................................... 66 APPENDIX I I I ................................................................................................................. 68 APPENDIX I V ..................................................................................................................... 70 SELECTED BIBLIOGRAPHY ............................................................................................ 72 IV Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Table Page 1. Measures of Sinuosity ............................................................................... 9 2. The Relationship Between Some of the Major Variables Affecting Channel Pattern .............................................................. 25 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES Figure Page 1. Channel-valley relationship in three hypothetical stream sections................................................................................................ 12 2. Athens Quadrangle, West Virginia ................................................... 14 3a. Average annual temperature range, U.S.A......................................... 29 b. Average annual discharge va ria b ility , U.S.A................................ 29 4a. Average daily temperature range, U.S.A............................................. 30 b. Average annual discharge v a ria b ility , U.S.A ................................ 30 5. Map of the conterminous United States, showing the location of sample sites and illustrating the method of sampling employed ....................................................................... 34 6. Average annual discharge va ria b ility , U.S.A., 1951-60, indicating the spatial relationship with channel pattern . ....................................................................................... 43 7. Southwest Missoula Quadrangle, Montana ...................................... 52 8. Bomarton Quadrangle, Texas ............................................................... 53 9. The channel pattern evolution of a hypothetical stream, in response to climatic change, under varying degrees of resistance to lateral channel migration as a result of bank resistance or topographic control ................................. 58 VI Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER I INTRODUCTION Purpose of This Study River channel patterns, "the aspect of a stream channel as seen from the a ir, on a map,"^ pose several fundamental problems which have defied satisfactory explanation. Such problems include adequate classi­ fication of channel patterns, together with why, and under what conditions, particular channel pattern types occur. In recent years, the literature on the subject has varied from broad deductive overviews of geographers such as W. M. Davis at the turn of the century, to detailed analytical studies performed by civ il engineers and hydrologists using complex statistical tools, working in the laboratory on flume experiments, or on the micro-scale in the fie ld . Thus, the modern trend in the study of channel patterns, as indeed in fluvial geomorphology as a whole, has been fir s t, a shift from the general to the specific, and second, a shift away from the field of geography. I t is the intention of the present study to reexamine the above mentioned problems employing a geo­ graphic approach. I t proposes to take a broad overview, analogous to that attempted by Davis, but retaining the quantitative, empirical approach perfected by subsequent workers. ^J. C. Brice, "Streams," Laboratory Studies in Geology, No. 207 (1962), 1. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The overview involves a consideration of fields of study beyond the sphere of hydrology or c iv il engineering, but which, nevertheless, have a direct bearing upon fluvial processes. This study, then, in keep­ ing with fundamental geographic methodology, is a synthesis
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