Comparative Physiography of the Lower Ganges and Lower Mississippi Valleys
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Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1955 Comparative Physiography of the Lower Ganges and Lower Mississippi Valleys. S. Ali ibne hamid Rizvi Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Rizvi, S. Ali ibne hamid, "Comparative Physiography of the Lower Ganges and Lower Mississippi Valleys." (1955). LSU Historical Dissertations and Theses. 109. https://digitalcommons.lsu.edu/gradschool_disstheses/109 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. COMPARATIVE PHYSIOGRAPHY OF THE LOWER GANGES AND LOWER MISSISSIPPI VALLEYS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Geography ^ by 9. Ali IJt**Hr Rizvi B*. A., Muslim University, l9Mf M. A*, Muslim University, 191*6 M. A., Muslim University, 191*6 May, 1955 EXAMINATION AND THESIS REPORT Candidate: ^ A li X. H. R iz v i Major Field: G eography Title of Thesis: Comparison Between Lower Mississippi and Lower Ganges* Brahmaputra Valleys Approved: Major Prj for And Chairman Dean of Gri ualc School EXAMINING COMMITTEE: 2m ----------- - m t o R ^ / q Date of Examination: ACKNOWLEDGMENT The author wishes to tender his sincere gratitude to Dr. Richard J. Russell for his direction and supervision of the work at every stage; to Dr. Fred B. Kniffen for his valuable suggestions and guidance; to Dr. Robert C. West for guidance in planning maps; and to Dr. William G. Haag, Mr. John Vann, Dr. William G. Mclntire, and Dr. James P. Morgan for their valuable criticism of manuscript and en couragement. Thanks are due to Mr. Iqbal Ahmed for drawing maps and to Miss Helen Harrell and Mrs. Joie R. Porter for typing dissertation. The author also wishes to express his sincere thanks to his niece, Miss Binte Zehra Rizvi, whose assistance in the preparation of maps at Aligarh has been of great value. ii TABLE OF CONTENTS CHAPTER PAGE ACKNOWLEDGMENT........................... ii TABLE OF CONTENTS........................ iii LIST OF PLATES........................... ix ABSTRACT................................. x INTRODUCTION............................. xiii I THE DRAINAGE BASIN OF THE GANGES RIVER... 1 PHYSICAL CHARACTERISTICS................. 1 THE GANGES AND ITS TRIBUTARIES.......... h The Ganges. ................... if The Jumna........................... & The S o n 10 The Ramganga........... •••••••••••••• 12 The Gandak........... .. ............ Ik The Kosi............................ 15 The Brahmaputra.................. 16 The Meghna ...... 21 CLIMATE AND VEGETATION................... 23 DIVISIONS OF THE GANGES VALLEY........... 28 The Upper Ganges Valley............. 31 The Middle Ganges Valley.......... 31 The Lower Ganges Valley •••••• 32 iii CHAPTER PAGE COMPARISON WITH THE MISSISSIPPI BASIN. 3L II OLDER GEOLOGIC FEATURES................ LI SIWALIK DRAINAGE SYSTEM............... LI Siwalik-Indobrahm Hypothesis......... LL Dismemberment of the Siwalik River System. .... ............ L9 THE GANGES STRUCTURAL TROUGH............... 53 Thickness of Deposits. •••••• ........ 55 Suess*s Explanation.................. 56 Burrard*s Hypothesis.................. 57 Oldham*s Interpretation of Geodetic Data............................. 59 THE INDUS AND BENGAL-ASSAM TROUGHS........ 63 COMPARISON OF GEOSYNCLIN ES IN THE GANGES AND MISSISSIPPI VALLEYS............... 66 Mississippi Structural Trough.... 66 Gulf Coast Geosyncline........... 69 III PLEISTOCENE TERRACES OF THE GANGES VALLEY.. 73 BASIC CONCEPTS......................... 7L Changes in the Level of Land and Sea.• 77 Correlation of European and North American Glacial and Interglacial Stages •••••••............ 76 Effect of Pleistocene Level Changes on Streams. ................ 79 PLEISTOCENE TERRACES IN THE GULF COAST AREA 81 The Prairie Terrace. ................. 82 iv CHAPTER PAGE The Montgomery Terrace............ 83 The Bentley Terrace. ...... 84 The Williana Terrace.................. 85 Pleistocene Stratigraphy. ..... ••••• 86 Mechanics of Terrace Formation......... 88 STUDY OF QUATERNARY IN INDIA................ 90 Quaternary Terminology of the Upper Ganges Valley..................... 94 Khadar and Bhangar ......... 96 Bhabar and Terai ................. 96 The "Old Alluvium” of the Lower Ganges Valley............................ 97 The Madhupur Jungle............... 99 The Barind........................ 101 The Lalmai Hills.................. 102 Speculations Regarding the Formation of "Old Alluvium"...... ..••.•••••••• 103 Are the Patches of "Old Alluvium" Pleistocene Terraces?............. 106 IV THE CHANGING DRAINAGE PATTERNS OF THE LOWER GANGES VALLEY.......................... 109 SOURCES OF INFORMATION...................... 109 Old Hindu Scriptures. ....... 110 Historical Records..................... 110 Travellerfs Accounts. .......... Ill Pt'olemy’s Description.......... Ill Archaelogical Evidence........ 112 Modern Maps .............. 112 CHAPTER PAGE THE POST-SIWALIK DRAINAGE.................... 113 MODERN DRAINAGE PATTERNS..................... 115 Rivers of the Fourteenth Century........ 115 Rivers of the Sixteenth Century....... 117 Rivers of the Seventeenth Century*•••••• 118 Rivers of the Eighteenth Century........ 121 EVOLUTION OF THE PRESENT RIVER SYSTEM....... 124 The Ganges-Brahmaputra Doab............. 126 The Meghna-Brahmaputra Valley.•••••••••• 128 The Deltaic Plain••••••••••••••••••••••• 132 BAERiS LAW IN RELATION TO BENGAL RIVERS.......133 V THE FLOOD PLAINS............................. 139 The Brahmaputra................*........ 139 The Ganges........ *..... *.............. 142 The Meghna******................ *........ 146 STREAM PATTERNS.............................. 146 Braided Patterns .................. 146 Meander Patterns ..... 149 LAND FORMS.................................... 151 Alluvial Cones ....... 151 Natural Levees...... 152 BHILS AND JHEELS............................. 154 Sylhet Jheels......... *................ 155 Chalan Bhil..... *....................... 156 vi CHAPTER PAGE VI THE DELTA.................................... 159 DEFINITION..*............................... 159 ESSENTIAL FEATURES OF A DELTA............... 163 STRUCTURE.................................... 160 The Bottomset Beds........... 170 The Foreset Beds....... 170 The Topset Beds............. 171 THE MISSISSIPPI DELTA....................... 174 THE GANGES DELTA................. 176 VII SURFACE FEATURE OF THE GANGES DELTA........ 167 RIVERS AND KHALS............................ 167 The Bhagirathi............... 16? The Jalangl......... 190 The Bhairab................••••••...... 191 The Matabhanga.•••••.•••••••••••••••••• 191 The Garai-Madhumati....... 192 The Arial Khan........ 193 The Padma..................... •••••.... 194- STREAM PATTERNS............ 196 Meander Patterns........ ........ 196 Network Patterns. ....... 197 Braided Patterns.......... 196 DEAD AND DYING RIVERS.......... 196 BHILS AND JHEELS............................ 204 vii CHAPTER PAGE LAND FORMS.................................. 208 Natural Levees. ..... 208 Dwips. ..... 210 SEDIMENTATION............................... 212 Sedimentary Load............. 212 Thickness of Sediments ....... 217 Growth of Delta........ 219 VIII MODERN SUBDELTAS OF THE GANGES.............. 221 The Bhagirathi Subdelta. ..... 227 The Bhairab Subdelta......... 229 The Matabhanga Subdelta....... 231 The Arial Khan Subdelta................ 233 The Garai-Madhuxnati Subdelta.......... 235 DIVISIONS OF THE DELTAIC PLAIN.............. 237 Moribund Delta...... ...••••«•......... 237 Mature Delta. .......... 239 Active Delta. 2i+0 IX SUMMARY AND CONCLUSIONS..................... 22+1 BIBLIOGRAPHY................................ 22+6 APPENDIX..................................... 259 BIOGRAPHY................................... 261 viil LIST OF PLATES PLATE PAGE I Drainage Basin of the Ganges Brahmaputra....... 5 II Divisions of the Ganges Valley. ............. 29 III Alluvial Valley of the Lower Mississippi River. 35 IV Evolution of the Himalayan Rivers.............. 43 V Lower Ganges Valley - Physical Features... 96 VI Van den Broucke*s Map of Bengal (1660)......... 119 VII Rivers of the Eighteenth Century............... 122 VIII Lower Ganges Valley - Drainage Patterns 125 IX A Bend of the Ganges....................... 143 X Ganges and Brahmaputra Delta (According to Lyell) Ganges Delta (According to Fox)............ •••••••••••• 176 XI Bengal Delta (According to Mukerjee) Ganges Delta (According to Bagchi)............. 161 XII The Ganges Delta.••••••••••• .........••••.... 168 XIII Bhagirathi Subdelta.. 226 XIV Bhairab Subdelta............... 228 XV Matabhanga Subdelta....... 230 XVI Arial Khan Subdelta............................. 232 XVII Garai-Madhuraati Subdelta ................ 234 XVIII The Ganges Delta - Subdivisions................ 238 ix ABSTRACT The Lower Ganges Valley is, in many respects, similar to the Alluvial Valley of the Lower Mississippi River# The Ganges and Bengal-Assam structural troughs are comparable to the Mississippi Structural Trough and Gulf Coast Geo- syncline,