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Drumlins in the Himalayas: Geography, Genesis, Classification and Evolutionary History

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Drumlins in the Himalayas: Geography, Genesis, Classification and Evolutionary History DRUMLINS IN THE HIMALAYAS: GEOGRAPHY, GENESIS, CLASSIFICATION AND EVOLUTIONARY HISTORY Dissertation submitted to Jawaharlal Nehru University in partial fulfillment of the requirement for the award of the degree of MASTER OF PHILOSOPHY SOURAV SAHA CENTRE FOR THE STUDY OF REGIONAL DEVELOPMENT SCHOOL OF SOCIAL SCIENCES JAWAHARLAL NEHRU UNIVERSITY NEW DELHI-110067 INDIA 2013 [email protected] [email protected] JAWAHARLAL NEHRU UNIVERSITY Centre for the Study of Regional Development School of Social Sciences New Delhi-110067 20 May, 2013 DECLARATION I, MR. SOURAV SAHA, hereby declare that the dissertation entitled “DRUMLINS IN THE HIMALAYAS: GEOGRAPHY, GENESIS, CLASSIFICATION AND EVOLUTIONARY HISTORY” submitted by me for the award of the degree of MASTER OF PHILOSOPHY is my bonafide work and that it has not been submitted so far in part or in full, for any degree or diploma of this university or any other university. SOURAV SAHA CERTIFICATE It is hereby recommended that the dissertation may be placed before the examiners for evaluation. Prof. P.M. Kulkarni Dr. Milap Chand Sharma (Chairperson) (Supervisor) ______________________________________________________________________________ Tel. :( 011) 26704463Ext. 2466, 2463 Gram: JAYENU Fax: 91-11- 26717586, 26197603 i DRUMLINS IN THE HIMALAYAS: GEOGRAPHY, GENESIS, CLASSIFICATION AND EVOLUTIONARY HISTORY Dissertation submitted to Jawaharlal Nehru University in partial fulfillment of the requirement for the award of the degree of MASTER OF PHILOSOPHY SOURAV SAHA CENTRE FOR THE STUDY OF REGIONAL DEVELOPMENT SCHOOL OF SOCIAL SCIENCES JAWAHARLAL NEHRU UNIVERSITY NEW DELHI-110067 INDIA 2013 ii Acknowledgement No piece of research work can be done in isolation. This humble effort of mine is also no exception. I owe this dissertation to the efforts and contributions of so many people. Without their help this would have been impossible for me. I wish I could mention all of them here. Foremost, I would like to express my sincere gratitude to my supervisor Dr. Milap Chand Sharma for his continuous support of my M.Phil. study and research. His patience, enthusiasm, and immense knowledge always motivated me for going for better work. His guidance helped me immensely not only during my filed work with him, but also all throughout my research and writing of this dissertation. He is a great human being who always teaches me how to behave with people and nature apart from how to passionate about research and understand the Mother Nature. His belief in god and his own senses also inspired me to belief mine during the field work. I could not have imagined having a better advisor and mentor for my M.Phil. study. I am deeply grateful to our Chairperson, Prof. P.M. Kulkarni for providing necessary infrastructure and resources to accomplish my research work. The always enthusiastic Prof. B.S. Butola, Dr. S. Sen, Dr. S. Sreekesh, Dr. M. Punia, Dr. D. Das and Dr. P. Pani of CSRD, JNU, also have always extended their support and belief to me and my work. I will always be owed to them. I am also extremely indebted to Dr. S.P. Shukla for his valuable suggestions and inspiration during the ‘Field Training Course in Glaciology’, Himachal Pradesh in 2012. I would like to extend huge, warm thanks to Dr. D. Srivastava for his valuable critique, Dr. R. Pal of AIRF, JNU, for her help during SEM analysis, Mr. Jamaica and Sani at Chandra Tal base camp for providing food during my solo field work, Mr. and Mrs. Dorjee at Batal camp, Mr. J. Thakur at ABVIMAS, Manali, and many more. I am also highly thankful to MA. Junior batch students, 2011-13 of CSRD, JNU; without their kind help and support it would be extremely hard for me during the first field work. I also express my thanks to Dr. Rakesh Arya, Prasenjit Acharya, Kamal Nag, Avijit Mistri, Vikas Aameria and Tara Shanker of CSRD, JNU for their technical and brotherly support. I am also indebted to the University Grants Commission (UGC) for providing financial assistance in the form of Junior Research Fellowship (JRF) which buttressed me like financially backward student to perform work comfortably. My thanks also go to HRTC for their effective and timely transport services in the remote areas of Lahul and Spiti, HP. Last but not the least, my especial thank to my god and my loving mother and sister. They have given me their univocal support and love throughout my work. Without their encouragement and boosting it would have been impossible for me to continue this work. Thanking you— Sourav Saha. iii Contents Pages Declaration and certificate i Acknowledgements iii List of Tables x List of Chart x List of Figures xi List of Plates xviii Chapter-1: Introduction to Drumlins 02-60 1.1 Statement of problem 1.2 Definition 1.3 Characteristics of drumlins 1.3.1 Morphological characteristics of drumlins 1.3.1.1 Drumlin spacing 1.3.1.2 Drumlin density 1.3.1.3 Drumlin distribution 1.3.1.4 Drumlin size and shape 1.3.2 Sedimentological characteristics of drumlins 1.3.2.1 Compositional characteristics 1.3.2.2 Structural characteristics 1.4 Association of drumlins with other subglacial landforms 1.5 Changing paradigm and thinking: Theoretical development in drumlin study 1.6 Relevance of drumlin study 1.7 Limitation of drumlin study 1.8 Distribution of drumlins in the world 1.9 Rationally behind the selection of the study area iv 1.10 Research questions 1.11 Objectives of the study 1.12 Data base 1.12.1 Primary data base 1.12.1.1 Data collected in the field 1.12.1.2 Data analysed in the laboratory 1.12.2 Secondary data 1.13 Achievements and scheme of chapterisation Chapter-2: Introduction to the study area 62-120 2.1 Introduction 2.2 The study area 2.2.1 The Lahul Himalaya 2.2.2 The Upper Spiti valley at Kunzum La 2.2.3 The Yunan basin of the Zanskar range 2.3 Geological characteristics and their significance in the present study 2.4 Geomorphological characteristics and their significance in the present study 2.4.1 Glacial geomorphology 2.4.2 Periglacial geomorphology 2.4.3 Paraglacial geomorphology and mass movement processes 2.4.4 Fluvial geomorphology and lacustrine deposits 2.5 The timing and extent of glaciation in the Lahul Himalaya and Zanskar 2.5.1 Timing and extent of glaciation in the Lahul Himalaya 2.5.1.1 Chandra stage glacial advance 2.5.1.2 Batal stage glacial advance 2.5.1.3 Kulti stage glacial advance 2.5.1.4 Sonapani I and Sonapani II glacial advance v 2.5.2 Timing and extent of glaciation in the Zanskar range 2.5.2.1 Chandra stage glacial advance or Zanskar 1 2.5.2.2 Batal stage glacial advance or Zanskar 2 2.5.2.3 Kulti stage glacial advance or Zanskar 3 2.5.2.4 Sonapani minor glacial advance or Zanskar 4 2.6 Palaeoenvironmental implication of glaciation in the study area and their importance to present study 2.7 Physiographic setting of the study area and their relevance in the present study Chapter-3: Glacigenic sedimentary characteristics and methodological applications 122-171 3.1 Introduction 3.2 Rationally behind the lithofacies study in the Himalayas 3.3 Terminological dilemma in glacial sedimentology 3.4 General methodological application in glacial sedimentology 3.4.1 Lithological analysis 3.4.1.1 Grain size analysis 3.4.1.2 Mineralogical analysis 3.4.1.3 Contact surface analysis 3.4.1.4 Analysis of the size and geometry of unit 3.4.1.5 Structural analysis 3.4.1.5.1 Glacial erosional structures 3.4.1.5.2 Palaeocurrent structures and stream deposits 3.4.1.5.3 Lacustrine depositional structures 3.4.1.5.4 Mass movement structures and dead-ice melting evidences 3.4.1.5.5 Deformation structures 3.4.2 Morphotextural analysis 3.4.2.1 Grain shape analysis vi 3.4.2.2 Grain sorting analysis 3.4.2.3 Clast roundness analysis 3.4.2.4 Grain surface textural analysis 3.4.2.5 Clast fabric analysis 3.5 Glacigenic sedimentary characteristics 3.5.1 Sedimentary characteristics of supraglacial subenvironment 3.5.2 Sedimentary characteristics of englacial subenvironment 3.5.3 Sedimentary characteristics of terminoglacial subenvironment 3.5.4 Sedimentary characteristics of subglacial subenvironment Chapter -4: Methodology and limitations of the study 173-194 4.1 Introduction to the basic framework of study 4.2 Primary data versus secondary data 4.3 Coding method 4.4 Methodology and limitations of the present study 4.3.1 Methodology for the primary data input 4.3.1.1 Preparation of the geomorphological maps 4.3.1.2 Clast macro fabric and shape and roundness analysis 4.3.1.3 Field exposures and sedimentary log preparation 4.3.1.4 Grain size analysis 4.3.1.5 Surface texture analysis of sand quartz grains using Scanning Electron Microscope (SEM) 4.3.1.6 Other primary data 4.3.2 Methodology for secondary data vii Chapter-5: Geographical distribution and morphological classes of the drumlins in the Study area 196-256 5.1 Introduction 5.2 Identification of drumlins in the field 5.3 Typical configuration of valley topography 5.4 Geographical distribution of drumlins in the Himalayas: A case study of Lahul Himal and Zanskar region 5.5 Location of ice divide at Baralacha La during extensive valley glaciation 5.6 Morphological Classification of drumlins a) Classical drumlins b) Superimposed drumlins c) Inverse drumlins d) Uniform drumlins Summery Chapter-6: The genesis and evolutionary history of drumlins in the Himalayas 258-327 6.1 Introduction 6.2 Analysis of the internal composition of drumlins 6.2.1 Lithological Analysis 6.2.1.1 Grain size analysis 6.2.1.2 Structural analysis 6.2.2 Morphotextural analysis 6.2.2.1 Grain shape analysis 6.2.2.2 Clast roundness analysis 6.2.2.3
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