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SEDIMENTOLOGICAL STUDY OF LOKAPUR SEQUENCE OF KALADGI BASIN, KARNATAKA, INDIA A THESIS SUBMITTED TO GOA UNIVERSITY FOR THE AWARD OF THE DEGREE OF DOCTOR OF PHILOSOPHY IN GEOLOGY by PURUSHOTTAM ANIL VERLEKAR Under the Guidance of Dr. Mahender Kotha School of Earth, Ocean and Atmospheric Sciences Goa University SCHOOL OF EARTH, OCEAN AND ATMOSPHERIC SCIENCES GOA UNIVERSITY FEBRUARY, 2021 This thesis is dedicated to My Grandmother Smt. Shantabai Shantaram Rivonkar CERTIFICATE This is to certify that the thesis titled, “Sedimentological study of Lokapur sequence of Kaladgi Basin, Karnataka, India” submitted by Purushottam Anil Verlekar for the award of degree of Doctor of Philosophy in Geology is a record of research work done by him during the period of study and is based on the results of experiments carried out by him independently. The thesis or a part thereof has not previously formed the basis for the award to the research scholar for any other degree, diploma, associate ship, fellowship or other similar titles. RESEARCH GUIDE Dr. Mahender Kotha Professor, School of Earth Ocean and Atmospheric Sciences Goa University, Taleigao Plateau, Goa STATEMENT I hereby state that this thesis titled, “Sedimentological study of Lokapur sequence of Kaladgi Basin, Karnataka, India” for the award of Ph.D. degree is my original contribution and that the thesis or any part thereof has not previously formed the basis for the award of any other degree, diploma or other similar titles of any university or institute. To the best of my knowledge, the present study is the first comprehensive study of its kind from the study area. The literature pertaining to the investigated problem has been duly acknowledged. Facilities availed from other sources have also been duly acknowledged. RESEARCH SCHOLAR Mr. Purushottam Anil Verlekar, School of Earth Ocean and Atmospheric Sciences Goa University, Taleigao Plateau, Goa. ACKNOWLEDGEMENT I am deeply obliged and thankful to my supervisor Prof. Mahender Kotha for his continued support throughout this work. His unshaken belief in me has brought this thesis to the present stage This thesis would not have got completed without the constructive and critical inputs of my VC’s nominee Dr. J. N. Pattan. My sincere thanks to Dr. A. A. Viegas for his constant motivation and encouragement in completing the scholarly work. A special word of gratitude to the three Deans, during whose tenure this work was undertaken. Prof. A. V. Salkar and Prof. Gourish Naik of Faculty of Natural Sciences, Goa University and Prof. H. B. Menon, Dean of School of Earth Ocean and Atmospheric Science. I thank my soulmate Gargi, who was pillar of strength. She doubled up as my field companion, her editing enriched the work and her science background became an added asset in writing the thesis. I wish to thank Adv. Surel Tilve, Shantal Rivankar and Abhishek Pissurlekar for their kind logistical support. It would have been not possible without support of my Uncles, Shashank Rivonkar, Nishant Rivonkar and Aunt Mrs. Nirmala Rivonkar, Mrs. Nehal Rivonkar for opening up their house to me and creating a serene atmosphere for me to complete this scholarly work. I am Indebted to Dr. Aditya Joshi for his kind hospitality during my stay at Vadodara. I acknowledge the Director, National Institute of Oceanography- Goa for providing XRD facilities and the Director, Regional Geoscience Lab-Vadodara for providing SEM facilities which has enhanced the quality of work. I am grateful to Nageshwar, Dwayne, Lewlynn, Satu, Gopal, Omkar, Aliston and Chinmay for spending their time with me in the field. I acknowledge the kind support and affection of Mr. Premanand Gauns, Mr. Devidas Gaude, Mrs. Sangita, Mr. Dynaneshwar and entire support staff of Earth Science Department, Goa University. I thank My colleagues, Dr. Niyati Kalangutkar, Dr. Sohini Ganguly and Mr. Raghav Gadgil for their constant support and encouragement at all times during the tenure of this thesis. I would like to thank My teacher Mr. Harish Nadkarni of Parvatibai Chowgule College for kindling the light which brought all frontiers of Geology to me. My humble thanks to my dearest sister Priyanka and brother in law Chetan for always being there with me and gratitude to my in-laws Kalpana and Kantikumar Lotlikar for their steadfast support. I remember the encouraging words of my uncle Late Mr. Manohar Verlekar as this thesis is completed. I am eternally indebted to my parents Kanchan and Anil Verlekar for taking me from the cradle to this memorable journey And finally, my deep reverence to Dambab for all blessings he showered upon me. C O N T E N T S Chapter No Topics Page no List of Figures iii List of Table vi Abstract 1 Chapter 1 INTRODUCTION 1.1 Foreword 4 1.2 Introduction 5 1.3 Aims and Objectives 6 1.4 Previous Work 6 Chapter 2 GEOLOGY AND STRATIGRAPHY 2.1 General 11 2.2 Stratigraphy of Kaladgi Supergroup 13 2.3 Study Area 21 Chapter 3 METHODOLOGY 3.1 Field work 36 3.2 Laboratory investigations 40 3.3 Scanning Electron Microscopy 41 3.4 X-Ray Diffraction 42 Chapter 4 CLASTIC SEDIMENTOLOGY 4.1 Introduction 46 4.2 Detrital mineral composition 46 4.2.1: Quartz 48 4.2.2: Lithic Fragments 49 4.2.3: Feldspars 50 4.2.4: Matrix and Cement 50 4.2.5: Clay minerals 51 4.2.6: Accessory minerals 51 4.3 Texture 52 4.3.1: Mean 54 4.3.2: Standard deviation 54 4.3.3: Inclusive graphic skewness 54 4.3.4: Inclusive graphic kurtosis 55 4.3.5: Textural maturity 55 4.4 Classification 56 4.5 Diagenesis 57 Chapter 5 CARBONATE PETROGRAPHY AND DIAGENESIS 5.1 Introduction 64 5.2 Fabric and Texture 65 5.3 Carbonate Petrography and classification 5.3.1: Micrites 66 5.3.2: Biomicrites 67 5.3.3: Algal laminated biomicrites 67 i 5.3.4: Dolomircites and sparites 67 5.4 Identification of Carbonate Minerals 5.4.1: X-ray diffraction analysis 68 5.4.2: Determination of Calcite – Dolomite ratio 70 5.4.3: Results 70 5.5 Geochemistry of Carbonate rocks 5.5.1: Analytical Methodology 71 5.5.2: Major and selected Minor elements 72 5.5.3: Other elements 75 5.5.4: Rare Earth Elements (REE) 75 5.6 Diagenesis 5.6.1: Diagenesis of Carbonate Units of Lokapur Subgroup 79 5.6.2: Compaction 80 5.6.3. Replacement 80 Chapter 6 PROVENANCE AND DEPOSITIONAL HISTORY 6.1 Introduction 93 6.2 Interpretations 93 6.3 Depositional Environments 95 6.4 Paleoclimate 99 Chapter 7 SUMMARY AND CONCLUSION 7.1 Summary 106 7.2 Conclusion 109 BIBLIOGRAPHY 112 ii List of Photos and Figures Figure Description Page No. 2.1. Geological Maps of study area Geological map of the Kaladgi Basin (after Jayaprakash et al., 26 1987; Dey et al., 2009). 2.2 Map showing Sample Location for Carbonate samples 27 (Mahender 2004) 2.3 a Symmetrical ripples with bifurcating crests 28 2.3 b Symmetrical ripples 2.4 Contact between basement and Mesoproterozoic rocks 29 2.5 Disoriented clasts floating in Conglomerate 2.6 Natural vegetation at Hooli 30 2.7 Conglomerate interlayered in Sandstone at Savadatti 2.8a Thickly bedded planar parallel beds (inclined) observed near 31 Ramdurg 2.8b Massive Sandstones devoid of any structure exposed near Savadatti 2.9a Deformed crystalline limestone at Lokapur 2.9b Widen joints in Limestone 32 2.10 Alternating bands of Carbonate and Shale 33 2.11 Bimodal grain size distribution seen at Munavalli 2.12 Trough cross bedding observed in stream cut section 34 2.13 Horizontally disposed beds of Shale 3.1 Techniques used for atmospheric SEM 44 3.2 TM-3000 table top SEM at RGL Vadodara 4.1 Ternary diagram for classification of Arenaceous rocks of 59 Saundatti Quartzite Member with matrix less than 15% (Pettijohn 1984, modified after Dott 1964) 4.2 Petrography of Clastic rocks 60 a. Clasts of Monocrystalline Quartz in moderately well sorted Arenite b. Grain of Polycrystalline composite Quartz seen in sample collected from Savadatti. c. Polycrystalline Schistose Quartz grain d. Grains of Lithic Fragments as seen sample from Hooli Village e. Grain of Plagioclase Feldspar seen forming framework constituent in one of the samples. f. Grains of Pressure Quartz seen as framework grains in sample collected from Savadatti 4.3 Accesory Minerals 61 iii a. SEM image showing Intergranular spaces occupied by Kaolinite b. SEM image of Vermiform overgrowth of Kaolinite seen in Void spaces c. SEM image showing well developed crystal faces of Kaolinite e. Distinct greenish to yellow coloured specs of Chloritoids, note flowage around quartz grains f. Slender prismatic habit of Tourmaline grain 4.4 Diagenesis 62 a. Quartz overgrowth around detrital grains. b. PPL image of well sorted Arenite with brownish ferruginous cement c. Corroded grain boundaries filled by clay minerals precipitated secondary minerals d. Framework grains exhibiting Sutured contacts in Sample collected from Lokapur e. Long contact observed along with deformation fractures seen in Sample from Hooli Village f. Subrounded grains of Quartz making framework 5.1 Field Photographs of Stromatolites 84 a. Typical concentric to cylindrical shaped stromatolites exposed at ground level near Lokapur. b. Outcrops of Dolomitic limestone showing folded structure exposed in fields around Lokapur. 5.2 Types of Stromatolites 85 a. Algal Stromatolite bedding of dolomitic limestone exposed on the Lokapur to Petlur Road b. Pseudo Columnar Stromatolites showing both upward convex and concave lamination (Lokapur) c. Deformed stromatolite mat seen in Dolomitic limestone d. Stromatolite possibly of Conophyton Cylindricus e. Common stromatolitic structures 5.3 Photomicrographs-Carbonates 86 a. Finely crystalline micritic limestone. (Petlur Limestone Member) XN b.