The Glacial Sequences in the Rangitata and Ashburton Valleys, South Island, New Zealand
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ERRATA p. 10, 1.17 for tufts read tuffs p. 68, 1.12 insert the following: c) Meltwater Channel Deposit Member. This member has been mapped at a single locality along the western margin of the Mesopotamia basin. Remnants of seven one-sided meltwater channels are preserved " p. 80, 1.24 should read: "The exposure occurs beneath a small area of undulating ablation moraine." p. 84, 1.17-18 should rea.d: "In the valley of Boundary stream " p. 123, 1.3 insert the following: " landforms of successive ice fluctuations is not continuous over sufficiently large areas." p. 162, 1.6 for patter read pattern p. 166, 1.27 insert the following: " in chapter 11 (p. 95)." p. 175, 1.18 should read: "At 0.3 km to the north is abel t of ablation moraine " p. 194, 1.28 should read: " ... the Burnham Formation extends 2.5 km we(3twards II THE GLACIAL SEQUENCES IN THE RANGITATA AND ASHBURTON VALLEYS, SOUTH ISLAND, NEW ZEALAND A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy in Geography in the University of Canterbury by M.C.G. Mabin -7 University of Canterbury 1980 i Frontispiece: "YE HORRIBYLE GLACIERS" (Butler 1862) "THE CLYDE GLACIER: Main source Alexander Turnbull Library of the River Clyde (Rangitata)". wellington, N.Z. John Gully, watercolour 44x62 cm. Painted from an ink and water colour sketch by J. von Haast. This painting shows the Clyde Glacier in March 1861. It has reached an advanced position just inside the remnant of a slightly older latero-terminal moraine ridge that is visible to the left of the small figure in the middle ground. Ablation moraine covers the entire glacier surface, and an end moraine is forming around part of the snout. Meltwater is discharging from a tunnel at the base of the clean-ice zone. ii C;:ONTENTS Page Contents ii List of Figures vi List of Tables viii List of Maps ix Acknowledgements x ABSTRACT 1 PART ONE: INTRODUCTION CHAPTER 1 GENERAL INTRODUCTION 3 1. Introduction 3 2. Scope of the Investigation 5 3. Thesis Layout 8 2 GEOLOGIC AND PHYSIOGRAPHIC BACKGROUND 9 1. Introduction 9 2. Geologic Setting 9 3. Late Cenozoic Development of Study Area 12 4. Physiographic Background 12 5. Conclusion 21 3 PREVIOUS WORK 22 1. Introduction 22 2. Previous Glacial Geomorphology 22 3. Other Related Research 23 4. Conclusion 24 4 MAPPING STYLES 25 1 • Introduction 25 2. Nature of the Field Area 25 3. Stratigraphic Maps 26 4. Geomorphological Maps 28 5 . Summary 29 iii CHAPTER Page 5 METHODS 30 1. Introduction 30 2. Work Programme 30 3. Source Materials 31 4. Field Techniques 32 6 CRITERIA FOR DIFFERENTIATING GLACIAL ADVANCES 35 1. Introduction 35 2. Nomenclature 36 3. Sequence of Advances 36 4. The Glacial Systems 37 5. Distinguishing Between the Advances 39 6. Defining the Glacial Sequences 40 7. Plains Surfaces 42 8. Presentation of Material 45 PART TWO: GLACIAL AND ASSOCIATED DEPOSITS AND LANDFORMS 7 THE PYRAMID ADVANCE 46 1. Introduction 46 2. Pyramid and Hororata Formations 46 8 THE DOGS HILL ADVANCE 53 1. Introduction 53 2. Dogs Hill and Woodlands Formations 53 9 THE TRINITY ADVANCE 63 1. Introduction 63 2. Trinity Formation 63 3. Windwhistle Formation 72 10 THE HAKATERE/EMILY ADVANCES 76 1. Introduction 76 2. Hakatere Formation 76 3. Emily Formation 83 4. Burnham Formation 89 1 1 THE SPIDER LAKES/LAKE HERON ADVANCES 92 1. Introduction 92 2. Spider Lakes Formation 92 iv CHAPTER Page 3. Lake Heron Formation 106 4. st. Bernard Formation 109 12 HOLOCENE FORMATIONS 112 1 . Introduction 112 2. Early Holocene Formations 113 3. Late Holocene Deposits 1 1 B PART THREE: THE MAJOR GLACIAL SEQUENCES 13 NOMENCLATURE OF MORAINES AND FLUVIOGLACIAL FEATURES ON MAPS 5-7 1 21 1 . Introduction 121 2. Nomenclature of Moraines and Fluvioglacial Features 122 14 THE GLACIAL SEQUENCE AT THE HEAD OF THE RANGITATA GORGE 130 1. Introduction 130 2. Physiographic Setting 130 3. The Glacial System 131 4. The Hakatere Advances 132 5. The Spider Lakes Advances 134 6. Deglacial Landforms 137 15 THE GLACIAL SEQUENCE IN THE LAKE CLEARWATER BASIN 140 1. Introduction 140 2. Physiographic Setting 140 3. The Glacial System 141 4 . The Hakatere Advances 143 5 . The Spider Lakes Advances 146 6 . Deglacial Landforms 154 16 THE GLACIAL SEQUENCE IN THE LAKE HER0N .BASIN 170 1 • Introduction 170 2. Physiographic Setting 170 3 . The Glacial Sy stem 171 4 • The Emily Advances 172 5 . The Lake Heron Advances 179 6 . Deglacial Landforms 1B4 v CHAPTER Page 17 THE RANGITATA-ASHBURTON SECTOR OF THE CANTERBURY PLAINS 190 1. Introduction 190 2. The Canterbury Plains 190 3. The Rangitata and Ashburton Sector of the Plains 193 PART FOUR: SYNTHESIS AND CORRELATION 18 THE GLACIAL CHRONOLOGY IN THE RANGITATA AND ASHBURTON VALLEYS 200 1. Criteria for Establishing Glacial Chronologies 200 2. The Glacial Chronology of the Rangitata and Ashburton Valleys 203 19 CORRELATION 207 1. Introduction 207 2. Methods of Correlating Glacial Chronologies 207 3. Correlation 209 4. The Glacial Chronology of the New Zealand Late Pleistocene 215 20 SUMMARY AND CONCLUSIONS 218 REFERENCES 221 APPENDICES 234 vi LIST OF FIGURES FIGURE Page Frontispiece: "Ye Horryble Glaciers", The Clyde Glacier i 1 Location Map 4 2 Other late Pleistocene Glacial Sequences Studied in the South Island 6 3 Generalised Geological Map 11 4 Physiographic Regions of the Study Area 15 5 Oblique Aerial View of Study Area 16 6 Limits of Late Pleistocene Glacial Advances in the Rangitata and Ashburton Valleys 38 7 Stereo triplet of part of the Lake Heron basin and foothill ranges (caption on facing page) 43 8 View west of part of the Lake Heron basin and foothill ranges 44 9 Profiles of major moraines and outwash surfaces (in map box) 10 View across Dogs Range towards Red Mountain 48 1 1 Pyramid formation till exposure in Blondin Creek Valley 50 12 Dogs Hill formation of foothill ranges at southern end of the Lake Stream basin 54 13 Woodlands Formation till near the downstream end of the Rangitata Gorge 57 14 Dogs Hill formation alluvial fan depos,i tl;> 59 15 Trinity Advance outwash surfaces at the southern end of the Lake Heron basin 66 16 View west of Trinity outwash surfaces 67 17 Windwhistle Formation alluvium exposed near the Inverary Station road bridge 74 18 View west across the southern end of the Mesopotamia basin 79 vii FIGURE Page 19 View south of moraines and outwash surfaces in the Upper Ashburton Valley 85 20 Geomorphological Map of Part of the Upper Ashburton Valley 86 21 View north across the Mesopotamia basin and Rangitata River 96 22 Spider Lakes formation t,ill near Black Birch Creek, Rangitata Valley 100 23 The Rangitata Gorge 111 24 Ablation moraine 125 25 Fluted ground moraine behind the Spider Lakes 3 end moraine 126 26 Ice disintegration moraine 127 27 Rangitata Valley at the head of the Gorge 131 28 Rangitata glacier ice limits during the Hakatere and Spider Lakes Advances 133 29 Clearwater lobe ice limits during the Hakatere and Spider Lakes Advances 142 30 Spider Lakes 1 end moraine ridge 148 31 Spider Lakes 3 Advance ice contact landform pattern 151 32 Part of the Spider Lakes 3 Advance end moraine ridge 152 33 Deglacial ice formlines in the Lake Clearwater basin 156 34 Profiles of deglacial ice formlines in the Lake Clearwater basin 157 35 Meltwater channels incised into ablation moraine near the eastern end of Lake Clearwater 161 36 Rakaia lobe ice limits during the Emily and Lake Heron Advances 174 37 Lake Heron and the Lake Stream Valley 181 38 Map of meltwater channels near southern shore of Lake Heron 186 viii LIST OF TABLES TABLE Page 1 Major glacial and meltwater systems in study area 35 2 Glacial sequences in the Rangitata and Ashburton Valleys 36 3 Criteria for differentiating glacial advances 41 4 Correlation of Late Pleistocene formations mapped in study area 45 5 The glacial chronology of the Rangitata and Ashburton Valleys 206 6 Correlation of glacial chronologies in the Canterbury region 214 ix LIST OF MAPS MAPS 1-4 1:50,000 scale maps of Late Quaternary Deposits in the foothill ranges, intermontane basins and inner plains margin areas of the Rangitata and Ashburton Rivers. In Map Box Key on separate sheet. In Map Box 5 1:25,000 scale map of the Geomorphology of the Rangitata Gorge District. In Map Box 6 1:25,000 scale map of the Geomorphology of the Lake Clearwater District. In Map Box 7 1:25,000 scale map of the Geomorphology of the Lake Heron District. In Map Box 8 1:250,000 scale map of the geology of the Canterbury Plains between the Rakaia and Orari Rivers. In Map Box x ACKNOWLEDGEMENTS I would like to thank my parents for their encouragement and generous financial assistance during the early stages of this work. Professor Jane Soons supervised this thesis. Her guidance and help with the field work and preparation of the text are greatly appreciated. The helpful discussions in the field with Dick Birnie, Peter Birkeland and Peter Oliver are gratefully acknowledged. My thanks also to David Bowen for his worthwhile criticisms of the early chapters. Accommodation in the field was kindly provided by Messrs J. Acland, A. Deans, W. Dobbs and M. Prouting. My thanks go to them and the other farmers in the area who allowed me on their land. Field work was made particularly pleasurable by the friendship and generosity of Mrs J. Thorndycroft. I am indebted to her for many weeks of comfortable accommodation and gourmet cooking.