EVOLUTION OF CHALIYAR RIVER DRAINAGE BASIN: INSIGHTS FROM TECTONIC GEOMORPHOLOGY Thesis submitted to the Cochin University of Science and Technology by Ambili V In partial fulfilment of the requirements for the award of the degree of DOCTOR OF PHILOSOPHY Under the Faculty of Marine Sciences Department of Marine Geology and Geophysics Cochin University of Science and Technology Cochin-682 016 October 2010 DECLARATION I hereby declare that the thesis entitled “Evolution of Chaliyar River Drainage Basin: Insights from Tectonic Geomorphology” is an authentic record of research work carried out by me under the supervision and guidance of Prof. A.C. Narayana, formerly from Department of Marine Geology and Geophysics, School of Marine Sciences, Cochin University of Science and Technology, in the partial fulfillment of the requirement of the Ph.D degree in the Faculty of Marine Sciences and no part thereof has been presented for the award of any other degree in any University/Institute. Cochin-682016 5 October 2010 Ambili V CERTIFICATE I certify that the thesis entitled, “Evolution of Chaliyar River Drainage Basin: Insights from Tectonic Geomorphology” is an authentic record of research work carried out by Ms. Ambili V under my supervision and guidance at the Department of Marine Geology and Geophysics, Cochin University of Science and Technology, in the Faculty of Marine Sciences in partial fulfilment of the requirements for the degree of Doctor of Philosophy and no part thereof has been presented for the award of any degree in any University/Institute. A. C. Narayana 1 October 2010 (Research Supervisor) Formerly Cochin University of Science and Technology ACKNOWLEDGEMENT This thesis would not have been possible without the guidance, support and help of several individuals who in one way or another contributed and extended their valuable assistance in the preparation and completion of the research work. It is a pleasure to convey my gratitude to them all in my humble acknowledgement. It is difficult to overstate my gratitude to Prof. A.C. Narayana, for his supervision, guidance and advice throughout the research work as well as providing me unflinching encouragement and support in various ways. His truly scientific intuition and passion to the subject exceptionally inspired me as a student, a researcher and a geologist. I am indebted to him and would have been lost without his support. I would like to gratefully acknowledge the support of some very special individuals. I owe a huge debt of gratitude to Dr. B.P. Radhakrishna, who had the patience to hear my work and give suggestions for improving the quality of the work. I am also grateful to Prof. Vishwas Kale for his valuable suggestions on varied aspects of my studies, even during his busy schedule. I sincerely thank Prof. C.G Nambiar, former Head, and Dr. M. Ravishankar, Head, Department of Marine Geology & Geophysics, for their timely suggestions and support in completing the work. I am thankful to the present and former Director, School of Marine Sciences, Cochin University of Science and Technology, for making facilities available during the period of my research. The support received from Prof. P. Seralathan and Prof. K. Sajan is acknowledged. I owe deepest gratitude to my organization, Geological Survey of India for giving permission to do research and also giving all the laboratory support required during the study. I am particularly grateful to Shri M.P. Muraleedharan, Director (Rtd.) for all the support provided for the field studies. I am greatly obliged to Shri S. Singanenjam, Supt. Geologist, for extending all the support during the final stage of the research work. I wish to express my warm and sincere thanks to Shri C. Muraleedhran, Sr. Geologist, GSI for supplementing my research work with some field data. I also warmly thank Shri P.S. Anil Kumar, Sr. Geologist, for the encouragement, support and advice during my difficult times as an elder brother. I extend my sincere thanks to my colleagues Dr. Mathew Joseph, M.N. Praveen, and Dr. Soney Kurien for their support during the research work. Many thanks go in particular to Kurien.V. Kunneth, Supt. Chemist for supporting me with all the laboratory facility for chemical analysis. I am grateful to Shri K.N.K Kartha, Sr. Chemist, Shri Rajashekharan and Shri N.S Nair (Chemists) for their constant support in analysing the samples. I am extremely thankful to Prof. K.V. Subbarao and other staff members of UCESS, University of Hyderabad, for rendering all the facilities during the final stages of the thesis. My sincere thanks are due to Dr. Rama Raju, Scientist (F), AMD, Hyderabad who gave lessons in raster analysis using GRASS. This work would not have been accomplished without the tremendous help and assistance rendered by Dr. Shinu. N, Yunus P, C. Remya, C.P.Ambika, Siva Parvathi, Ganga Bhavani, Naga Lakshmi V, Dr. C.P. Priju, N. Sravanthi, Sarang P.B, Dr. Sheena V. Dev, Vinu Prakash, Dr. K.P. Jaikiran, Dr, Lasitha, Dr. Nisha, Biju Longhinos, K.B Santhosh and Vinod. I thank all the non-teaching staffs of the Department of Marine Geology and Geophysics and School of Marine Sciences for their help. I am grateful to my undergraduate teachers, Dr. P.K. Sabu, Shri Benno Joseph, Dr. K.N. Krishna Kumar and Shri S.S. Anil Kumar who created a passion for the subject. My post graduate teachers Dr. M.S. Pandian is greatly acknowledged for his untimely support. I am out of words to express my respect and gratitude to my parents who supported me, taught me, guided me and loved me. Their blessings, moral and physical support made this thesis possible. I am grateful to my brother Arjun for his constant support and encouragement. I express my love and thanks to my in laws for their support during the research work. I am indebted to my husband Premesh for his understanding, endless patience and constant encouragement to improve my academic qualification and knowledge. I really feel proud of my six year old son, Amithrajith, who has adjusted and sacrificed my care on many occasions during this period. I pray to thee, the Almighty without His grace nothing is possible. Ambili V CONTENTS Page No. Chapter 1 Introduction 1-19 1.1 General 1.2 International and National Status of Tectonic Geomorphology 1.3 Objectives of the present work 1.4 Study area 1.5 Previous work in the study area 1.6 Physiography 1.7 Regional geology 1.8 Geology of the study area 1.9 Climate Chapter II Morphometry 20-48 2.1 Introduction 2.2 Materials and Methods 2.2.1 Linear aspects 2.2.2 Areal aspects 2.2.3 Relief aspects 2.2.4 Hypsometric analysis 2.3 Results and Discussion 2.3.1 Morphometric characteristics 2.3.2 Hypsometry 2.4 Summary Chapter III Drainage characteristics and Landforms 49-90 3.1 Introduction 3.2 Methodology 3.2.1 Materials and data used 3.2.2 Drainage analysis 3.2.3 Stream classification 3.2.4 Delineation of landforms 3.3 Results and Discussion 3.3.1 Drainage network 3.3.2 Streams and their behaviour 3.3.3 Landforms 3.4 Summary Chapter IV Field Geology and Geomorphology 91-126 4.1 Introduction 4.2 Lithology 4.3 Structure 4.4 Landforms 4.4.1 Erosional landforms in the upper reaches of the Chaliyar River drainage basin 4.4.2 Fluvial landforms 4.5 Field evidences of active tectonism 4.5.1 Unpaired terraces 4.5.2 Deflected stream 4.5.3 Palaeo-alluvial fans 4.5.4 Landslides 4.5.5 Faults 4.6 Summary Chapter V Tectonic Geomorphology 127-195 5.1 Introduction 5.2 Methodology 5.2.1 Stream profile analysis 5.2.2 Quantification of geomorphic indices 5.2.3 Delineation of geomorphic markers 5.2.4 Morphostructural analysis 5.3 Results and Discussion 5.3.1 River profiles 5.3.2 Geomorphic indices of active tectonics 5.3.3 Geomorphic markers of active tectonics 5.4 Lineaments 5.5 Morphostructures 5.6 Class designation of relative tectonic activity 5.7 Process response model of active tectonics 5.8 Summary Chapter VI Sedimentology 196-218 6.1 Introduction 6.2 Materials and Methods 6.2.1 Sediment samples 6.2.2 Textural analysis 6.2.3 Geochemical analysis 6.3 Results and Discussion 6.3.1 Texture 6.3.2 Bivariate plots 6.4 Geochemistry 6.5 Depositional environment 6.6 Summary Chapter VII Summary and Conclusion 219-230 7.1 Summary and Conclusion 7.2 Recommendation References 231-258 LIST OF TABLES Table. 1.1 General geology of Chaliyar River drainage basin (GSI, 1995 ) Table 2.1 Linear morphometric parameters of sub-basins of Chaliyar River and its drainage basin. Table 2.2 Bifurcation ratio and hierarchical morphometric parameters of the Chaliyar River drainage network Table 2.3 Areal morphometric aspects of nine sub-basins of Chaliyar River and its total drainage basin of Chaliyar River (C: total drainage basin). Table 2.4 Relief morphometric aspects of all nine sub-basins of Chaliyar River and total drainage basin of Chaliyar River (C: total drainage basin). Table 2.5 Mean, minimum and maximum elevations and the computed hypsometric integral of nine sub-basins. C represents the total drainage basin. Table 3.1 Average valley slope of the Chaliyar River along its profile. The river was divided into 17 segments along the profile. Table 3.2 Sinuosity ranges computed for segments along river centre line and sinuosity categories (after Brice 1982). Table 3.3 Sinuosity computed for the segments of the tributaries and trunk system of Chaliyar River. Table 3.4 Width to height ratio computed for the trunk stream of Chaliyar River with stream type (Rosgen, 1986 and Harman et al., 1999).