Seismic Hazard Assessment of Eastern Salt Range, Pakistan Submitted by Ahsan Ul Haq Under the Supervision of Prof. Dr. Muhammad
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1 Seismic Hazard Assessment of Eastern Salt Range, Pakistan Submitted by Ahsan Ul Haq Under the supervision of Prof. Dr. Muhammad Nawaz Chaudhry Prof. Dr.Jean-Pierre BURG 2 Thesis submitted for the Partial Fulfillment of the requirement for the degree of Doctor of Philosophy College of Earth & Environmental Sciences University of the Punjab, Lahore (2015) 3 Dedication I dedicate this thesis to my beloved mother who gave me affection and encouragement in every sphere of life 4 Certificate of Approval This thesis by Ahsan ul Haq is hereby approved for submission to the University of the Punjab, Lahore for the partial fulfillment of the requirement for the degree of Doctor of Philosophy in Earth Sciences (Geology). 5 Dr. Muhammad Nawaz Ch. (PhD, F.P.A.S) Prof. Dr. Jean-Pierre Burg Professor Emeritus, Director, College of Earth and D-ERDW-Institute of Geology, Environmental Sciences, CH-8092 Zurich Quaid-e-Azam Campus, ETH-Zurich - Sonnegstrasse, 5, University of the Punjab, Switzerland. Lahore. 6 Seismic Hazard Assessment of Eastern Salt Range, Pakistan Ahsan ul Haq Abstract This research investigates neotectonics and seismic risk assessment for the future development in the light of historic recorded earthquakes that caused a huge damage to human life and property. With the help of recent data, geological and neotectonic interpretations were carried out and high seismic areas have been identified. Computer modeling studies with the use of historic and recent seismic data provided peak ground acceleration, peak ground velocity and maximum credible earthquake of the investigated area. This present study indicates that Peak Ground Acceleration (PGA) for soil and rock is 268 gals (0.26 g). Maximum Credible Earthquake (MCE) includes both the low and high values of Peak Ground Acceleration (PGA) which in the context of Joggi Tilla fault and Tilla range fault are 0.26 g and 0.15 g respectively. The study of earthquake ground motions and associated earthquake hazards and risks plays an important role in the sustainable development of countries like Pakistan, where devastating earthquakes have occurred repeatedly. The devastating earthquake of 8th October, 2005 in Kashmir and adjacent areas produced good neotectonic features on mesoscopic to regional scale therefore, resulting in drawing attention of the worldwide geoscientific researchers. This present study is particularly valuable as it contributes to mitigation of earthquake risk as well as post-earthquake management of the disasters. The study is in particular concerned with obtaining an estimate of the ground motion parameters of the study area for the purpose of earthquake resistant design or seismic safety assessment. 7 Lithology, neotectonics and seismic behavior of the Eastern Salt Range was studied. For this purpose, the field analysis of complemented Geological, historical and instrumental earthquake data was carried out. The continuing collision between the Eurasian and Indian plates resulted in compressional forces in the North – West Himalayan Fold and Thrust Belt. Neotectonic features of the study area were studied using satellite image analysis and field observations. Tilting of recent sediments pattern was used as an indicator of neotectonic activity within the study area on satellite images. Field evidences of neotectonic activity along faults present in the study area include, tilting of quaternary sediments, stream offset and dissected sedimentation bars. Another characteristics feature is the change in topographic relief across the trace of fault. The Eastern Salt Range experienced 190 earthquakes of magnitude 1 to 3.9, 13 earthquakes of magnitude 4.00 to 4.9 and only four events of magnitude from 5.00 to 5.9. On the basis of historical and instrumental records, the area has not experienced moderate to large earthquakes. The investigated area is a part of eastern margin of Salt Range and consists of number of faults. The seismogenic sources and active faults of this zone are Salt Range Thrust, ChoaSayyaidan Shah Fault, KallarKahar Fault, Jhelum Fault, Joggi Tilla fault and Tilla Range faults etc. In the present study an attempt has been made, for the first time, to identify the surface/subsurface structural pattern for the area of Eastern Salt Range with the help of seismotectonics and neotectonics studies / techniques that are widely known for interpreting structural traps at depth and movements in faults. For this purpose all available earthquake data (during 0900-2008) from international seismological networks and the local seismic observatories have been collected for the compilation of seismicity map of the area. 8 Acknowledgments I am greatly thankful to my honorable and most respected supervisor Prof. Dr. Muhammad Nawaz Chaudhry Professor Emeritus, University of the Punjab, Lahore, who took great pain in the field work and research work, extending every possible facility and vast splendid research experience to solve various problems relating to the research work. His personal and professional advice, moral and administrative support may also not be left unmentioned in this regard. Next, I would like to thank my supervisor Prof. Dr. Jean-Pierre Burg, Director, Institute of Geology, ETH-Zurich, Switzerland, for his enthusiasm and interest in my work, for his patience and support during writing and documentation of the research, for his constant support, for taking time for the many constructive discussions. I would like to pay my heartiest tribute to officers of Geological Survey of Pakistan, Pakistan Atomic Energy Mineral Centre Lahore, Pakistan Meteorological Department Islamabad, Pakistan Council for Research in Water Resources, Quaid-e- Azam University Islamabad, University of Peshawar, University of Engineering and Technology Lahore, University of the Punjab Lahore, Pakistan etc., for their cooperation and permission to use data from various Geological and Engineering Seismological Technical Reports. I am deeply grateful to Dr. Ch. Muzaffar Majid and Mr. Imran, College of Earth and Environmental Sciences, University of the Punjab, Lahore and my dear fellows Mr. Kashif Butt, Mr. Kamran Bashir,Mr. Shah Alam and Mr. Shafique for their great cooperation. Above all, I am grateful to my family for sparing me during the time when my attention towards domestic affairs was urgently required, especially to my mother for her moral support, encouragement and prayers. May ALLAH bless all those who help me in the duration of my educational career SEISMIC HAZARD ASSESSMENT OF EASTERN SALT RANGE, PAKISTAN 9 Contents Page Number Abstract Acknowledgements List of Figures.......................................................................................................................... i List of Tables ....................................................................................................................... viii List of Maps ........................................................................................................................... ix Chapter One Introduction 1. Introduction .......................................................................................................................1 1.2 Location and Accessibility .....................................................................................2 1.3 Physiography ..........................................................................................................3 1.4 Scope of the Work ..................................................................................................5 1.5 Objective of the Study ............................................................................................7 1.6 Previous Work ........................................................................................................7 1.7 National Data ..........................................................................................................8 1.7.1 Geological Survey of Pakistan ....................................................................8 1.7.2 The PMD Historical Database ....................................................................8 1.7.3 Hydrocarbon Development Institute of Pakistan .......................................9 1.8 International Data ...................................................................................................9 1.8.1 The USGS Historical Database...................................................................9 1.8.2 The ISC Instrumental Database ..................................................................9 1.8.3 The Harvard Instrumental Database .........................................................10 1.8.4 The PDE-NEIC Database ..........................................................................10 1.9 Literature Review .................................................................................................10 1.10 Work Plan and Methodology ...............................................................................13 1.11 Organization of the Thesis ...................................................................................14 Chapter Two Stratigraphy 2. Stratigraphy .....................................................................................................................21 2.1 Geological Mapping ............................................................................................ 21 2.2 Regional Stratigraphy of the Study Area ........................................................... 23 2.3 Salt Range Formation .........................................................................................