Recurrent voluminous sector collapses at Volcán Barú, Panama

III ACKNOWLEDGEMENTS IV CONTENTS VI FIGURES VIII TABLES X INTRODUCTION 2 GEOLOGIC SETTING 2 RECENT ACTIVITY 3 TERMINOLOGY 5 METHODS 8 FIELDWORK 8 HUMMOCKS: DIGITIZING 10 DEBRIS AVALANCHE DEPOSITS 12 BARRILES DEPOSIT (VDADII) 13 CAISÁN DEPOSIT (VDADI) 16 SEDIMENTARY ARCHITECTURE 22 SUMMARY OF FIELD CHARACTERISTICS 23 RADIOCARBON DATING 26 HUMMOCK GEOMETRY AND DISTRIBUTION 27 HUMMOCK PROXIMITY 31 VOLUME CALCULATION: DEPOSIT THICKNESSES 34 VOLUME CALCULATIONS: EDIFICE RECONSTRUCTION 38 DISCUSSION 44 SOURCES AND TIMING OF EVENTS 44 HUMMOCK DATA COMPARISONS 48 VDAD MOBILITY 50 CONCLUSIONS 53 vii REFERENCES 55 APPENDIX 61 LOCATION MAP 61 DEPOSIT MINERALOGY 62 REGIONAL GEOLOGY 63 RADIOCARBON PLOTS 65 MAP OF HUMMOCK ORIENTATIONS 66 MAPS OF DEPOSITS AND HUMMOCKS 67