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J L E S

NUMERICAL MODELING TECHNIQUE FOR PREDICTING THE SEISMIC FAULT ZONE (SFZ) IN THE EARTHQUAKES AFFECTED AREA, NW HIMALAYAS WITH ITS NEOTECTONIC IMPLICATION

By: M. Farhad Howladar, Sharmin Afroz, Shofiqul Islam

Key Words: NW Himalaya, numerical technique, seismic fault zone, neotectonics

JLES-Vol-2-No-P-57-65, December 2007

Abstract

Finite elements analysis is a powerful tool, often used for analyzing problems on stress, that can be successfully employed to analyze the finite deformation of geological structures in a mathematical form on a digital computer. Over the last century, great earthquakes with magnitudes of 7->8 have struck in the NW Himalaya; the 1905 Kangra earthquake is one of them. This study performed a plane strain analysis of failure stress and faults in these earthquakes potential region based on the seismic geologic cross profile employing the two-dimensional finite element method under elastic material state with Mohr Coulomb failure criterion. The results show that the normal fault initiates at deeper level, whereas with increasing convergent displacement the thrust fault appears in the shallower region. The results of the simulation are compared with the available seismic and earthquakes focal mechanism solution data of the area which shows the close similarities between the distribution of simulated fault and microseismicity in the deeper region of Chamba Nappe (CN) and along the upper part of the Mid Crustal Ramp (MCR) which might be the Seismic Fault Zone (SFZ) of the region. Moreover, the intense localization of faults along the frontal part of the model indicates that this part is active in nature at present, which is responsible for the neotectonics in the Himalayas.

Anderson EM. 1951 (1st edn). The dynamics of faulting and dyke formation with applications to Britain. Edinburgh, 206 pp.

Ambraseys NN, Douglas J. 2004. Magnitude calibration of north Indian earthquakes. J Geophys J Int 158, 1-42.

Ambraseys N, Jackson D. 2003. A note on early earthquakes in northern India and southern Tibet. Current Sci 84(4),

571-582.

Armbuster J, Seeber L, Jacob KH. 1978. The northwestern termination of the Himalayan mountain front: Active tectonics from microearthquakes. J Geophys Res 83, 269-282.

Bilham R. 2004. Earthquakes in India and the Himalaya: tectonics, geodesy and history, Annals Geophys 47(2), 839- 858.

Blisniuk P, Hacker BR, Glodny J, Ratschbacher J, Bi S, Wu Z, Mcwilliams MO, Calvert A. 2001. Normal faulting in central Tibet since at least 13.5 Ma ago. Nature, 412, 628-632.

Chandra U. 1978. Seismicity, Earthquake Mechanisms and tectonics along the Himalayan mountain range and vicinity. Phys Earth Planet Inter 16, 109-131.

Cloetingh S, Wortel R. 1986. Stress in the Indo-Australian plate. Tectonophysics 132, 49-67.

Himalayan orogenic belt in Nepal. Science 288, 497-499.

Gansser A. 1964. Geology of the Himalayas: London, Wiley           Schelling D, Arita K. 1991. Thrust tectonics, crustal Inter. Science, 289 pp.                                                                        shortening and structure of the far eastern Nepal

Himalaya. Tectonics 10, 851-862.

DeCelles PG, Gehrels GE, Quade J, LaReau B, Spurlin M. 2000. Tectonic implications of U-Pb zircon ages of the

65

Tapponnier P. 1977. Structure and tectonics of Himalaya: A brief summary of relevant geophysical observations of Himalaya. Science de la Terre, Center National de la Recherche Scientique, Paris. 11, 269-294.

Nakata T, Otsuki K, Khan S, M. 1990. Active faults, stress field and plate motion along the Indo-Eurasian plate boundary. Tectonophysics 181, 83-95.

Nakata T. 1989. Active faults of the Himalaya of India and Nepal. Special paper Geol Soc America 232, 243-264.

Nakata T, Iwata S, Yamanaka H, Yagi H, Maemoku H. 1984. Tectonic landforms of several active faults in the western Nepal Himalayas. J Nepal Geol Soc 4, 177-200.

Pandey MR, Tandukar RP, Avouac JP, Lave J, Massot JP. 1995. Interseismic strain accumulation on the Himalayan crustal ramp (Nepal). J Geophys Res Letter 22, 751-754.

Powers PM, Lillie RJ, Yeats RS. 1998. Structure and shortening of the Kangra and Dehra Dun reentrants, Sub- Himalaya, India. Bull Geol Soc America 110, 1010– 1027.Modeling technique for predicting earthquakes

Howladar MF, Hayashi D. 2004. Simulation of Himalayan major thrusts by finite element method. J Geoinformatics 15(4), 207-219.

Howladar M F, Hayashi D. 2003. Numerical fault simulation in the Himalaya with 2D finite element method. J Polar Geoscience 16, 243-258.

Hua Wang, Linlin Ge, Caijun Xu, Zhixing. 2007. 3-D coseismic displacement field of the 2005 Kashmir earthquake inferred from satellite radar imagery. J Earth Planets Space 59(5), 343-349.

Jacob KH, Armbuster J, Seeber L, Pennington W. 1976. Tarbela reservoir:A region of compressional tectonics with reduced seism city upon initial reservoir filling. First Int. Symp. In induced seism city (ISIS), Banff, Canada, Engineering Geology.

Kaneko Y. 1997. Two-step exhumation model of the Himalayan metamorphic Belt, central Nepal. J Geol Soc Japan 103(3), 203-226.

Kano T. 1984. Geology and structure of the Main Central Thrust zone of the Annapurana range, Central Nepal Himalayas. J Geol Soc Japan 2, 31-50.

Lave J, Avouac JP. 2000. Active folding of fluvial terraces across the Siwaliks Hills, Himalayas of central Nepal. J Geophys Res 105, 5735-5770.

Lyon-Caen H, Molnar P. 1983. Constraints on the structure of the Himalaya from an analysis of gravity anomalies and a flexural model of the lithosphere. J Geophys Res 8B(10), 8171-8191.

Molnar P, Tapponnier P. 1978. Active tectonics of Tibet. J Geophys Res 83, 5361-5375.

Molnar P, Fitch TJ, Wu FT, Chen WP, Warsi WEK,

Seeber L, Armbruster JG, Quittmeyer RC. 1981. Seismicity and continental subduction in the Himalayan Arc. Geodynamic Series 3, 215-242.

Searle MP, Windley BF, Coward DJW, Rex AJ, Rex D, Tindong Li, Xuchang X, Jan MQ, Thakur VC, Kumar S. 1987. The closing of Tethys and the tectonics of the Himalaya. Geol Soc Bull America 98, 678-701.

Shanker D, Kapur N, Shing, B. 2002. Thrust-wedge mechanics and coeval development of normal and reverse faults in the Himalayas. J Geol Soc London 159, 273- 280.

Thakur VC. 2004. Active tectonics of Himalayan Frontal Thrust and Seismic Hazard to Ganga Plain. Current Sci 86, 1554-1560.

Thakur VC, Sriram V, Mundepi AK. 2000. Seismotectonics of the great 1905 Kangra earthquake meizoseismal region in Kangra-Chamba, NW Himalaya. Tectonophysics 326, 289-298.

Thakur VC. 1992. Geology of the Western Himalaya. Perga beneath the Himalaya. J Geophys Res 89, 1143–1147.

Upreti BN. 1999. An overview of the stratigraphy and tectonics of the Nepal Himalaya. J Asian Earth Sci 17, 577-606.

Verma RK. 1997. Paleomagnetism from Parts of Tethys Himalaya, Indus Suture Zone, Ladakh and South Tibet: Implications for Collision between Indian and Eurasian Plate. J Himalayan Geol 18, 93-102.

Yeats, Lillie. 1991. Contemporary tectonics of Himalayan frontal fault system: folds, blind thrust and the 1905 Kangra earthquake. J Structural Geology 13, 215-225.

Zienkiewicz OC, Cheung K. 1967. The finite element method in structural and continuum mechanics. McGraw-Hill

Publishing Co. Ltd., England.

M. Farhad Howladar, Sharmin Afroz, Shofiqul Islam

NUMERICAL MODELING TECHNIQUE FOR PREDICTING THE SEISMIC FAULT ZONE (SFZ) IN THE EARTHQUAKES AFFECTED AREA, NW HIMALAYAS WITH ITS NEOTECTONIC IMPLICATION

JLES-Vol-2-No-P-57-65, December 2007

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