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Experimental Models of Transfer Zones in Rift Settings Dpaul.Pdf Experimental Models of Transfer Zones in Rift Settings Debapriya Paul and Shankar Mitra 1. Introduction: 2. Experimental Approach 3. Fault Configurations 4. 3-D Fault Modeling Transfer zones are common features in rift basins, where deformation between normal faults is accommodated by the formation of oblique structures and complex secondary fault systems. The transfer zones result from Based on Morley et al, 1990 the interference between adjacent laterally a. Convergent b. Divergent c. Synthetic Transfer propagating normal faults. Three common Transfer Zone Transfer Zone Zone types of transfer zones are: (1) Convergent, with the main faults dipping towards each other (2) Divergent, with the main faults dipping away from each other, and (3) Syn- thetic, with the faults dipping in the same direction. Miller and Mitra, 2011 Unsmoothed surface Unsmoothed surface with fault cuts Smoothed surface with fault cuts and contours 5. Convergent Transfer Zone 6. Divergent Transfer Zone 7. Synthetic Transfer Zone Return to Regional Comparison of divergent Transfer Zones Comparison of Convergent Comparison of divergent Transfer Zones Transfer Zones Downdrop along dip Regional Dip Progressive Evolution of Progressive Evolution of Progressive Evolution of Convergent Transfer Zone Divergent Transfer Zone Upward Decrease in Width Synthetic Transfer Zone 7. Transfer Zones in East African Rift System 8. Extensional Forced 9. Conclusions References Bose, S. and S. Mitra, 2010, Analog modeling of divergent and Folds, Gulf of Suez convergent transfer zones in listric normal fault systems: AAPG Bulletin, v.94, p.1425-1452. Ebinger, C. J., 1989, Geometric and kinematic development of border faults and accommodation zones, Kivu-Rusizi Rift, Africa: tectonics, v.8, no.1, p.117-133. McClay, K.R., T. Dooley, P. Whitehouse and M. Mills, 2002, 4-D evolution of rift systems: Insights from scaled physical models: AAPG Bulletin, v.86, no.6, p.935-959. Miller J. F. and S. Mitra, 2011, Deformation and secondary faulting associated with basement-involved compressional and extensional structures: AAPG Bulletin,v.95, no.4, p.675-689. Morley, C.K., R.A. Nelson, T.L. Patton and S.G. Munn, 1990, Transfer Zones in east African rift system and their relevance to hydrocarbon exploration in rifts: AAPG Bulletin, v.74, no.8, p.1274-1253. The initial geometry of the faults (approaching, laterally offset, or overlap- Moustafa, A. R., 2002, Controls on the geometry of transfer zones in the Suez Rift and northwest Red Sea: Implications for the ping) controls the degree of overlap and the width of the transfer zones. structural geometry of the rift systems: AAPG Bulletin, v.86, no.6, p.979-1002. The transfer zones are marked by a change in relief from the footwall to the Paul, D. and S. Mitra, 2013, Experimental models of transfer zones in hanging wall rift systems: AAPG Bulletin, v.97, no.5, p.759-780. Moustafa, 2002 For communication email Id: [email protected] .
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