Document Type : Original Research Paper

Authors

1 Geology Department, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran.

2 Geological Survery and Mining Exploration of Iran, Tehran, Iran.

3 International Institute of Earthquake Engineering and Seismology, Tehran, Iran.

Abstract

The Chenareh Anticline is located between Lurestan Zone (in north) and Dezful Embayment (in south) in the Zagros Folded-Thrust Belt. This anticline is documented and interpreted to constrain the kinematic evolution of a fold. The development of fractures is confined to the Asmari Formation. In the study area, the fracture pattern is interpreted to identify six main fracture sets (from A to F). The first fracture set (A) striking 68, oblique to the further fold trend, is interpreted as a regional fracture set that predates compression phase. The second set (B) striking 110, parallel to the fold trend, are found in both limbs and interpreted as extensional fractures. Two other fractures set, (D, E) striking 10-70 and 80-140 are conjugate fractures existing in both limbs. The youngest fracture set (E) had formed during the folding process especially at the late stage of fold growth. Later on the first fracture group (A) are reactivated and called as (F) fracture set. Due to geometric characteristics of the Chenareh Anticline, it is categorized as a fault -propagation fold which is affected by the blind Balarud fault zone. The Z-shaped hinge zone of present anticline is attributed to the linkage of the two early individual anticlines.

Keywords

References
Armstrong, P. A. & Bartley, J. M., 1993- Displacement and deformation associated with a lateral thrust termination, Southern Golden Gate Range, SothernNevada, U.S.A.. Journal of Structural Geology, Vol.15, P.721-735.
Bellahsen, N. , Fiore, P. E. & Pollard, D.D., 2006- The role of fractures in the structural interpretation of Sheep Mountain Anticline, Wyoming. Journal of Structural Geology, Vol.28, P.850-867.
Bellahsen, N. , Fiore, P. E. & Pollard, D.D., 2007- From spatial variation of fracture patterns to fold kinematics: A geomechanical approach. Geophysical Research Letters, Vol.33, P.1-4.
Bergbauer, S. & Pollard, D.D., 2004- A new conceptual fold-fracture model including prefolding joints, based on field data from the Emigrant Gap Anticline, Wyoming. Bulletin Geological Society of America, Vol.116, P.294-309.
Bump, A. P., 2003- Reactivation, trishear modeling, and folded basement in Laramide uplifts: implications for the origins of infra-continental faults. Geological Society of America Today, Vol.13, P.4-10.
Chester, J. & Chester, J., 1990- Fault-propagation folds above thrusts with constant dip. Journal of Structural Geology, Vol.12, P.903-910.
Cloos, H., 1948- Gang und Gehwerk einer Falte. Zeitschr. Deutsch. Geol. Ges., Vol.100, P.290-303.
Cristallini, E. O. & Allmendinger, R. W., 2002- Backlimb trishear, a kinematic model for curved folds developed over angular fault bends. Journal of Structural Geology, Vol.24, P.289-295.
Davis, G. H. & Reynolds, S. J., 1996- Structural Geology of Rocks and Regions, John Wiley & Sons, Inc., 776pp.
Duune, W. M., 1986- Mesostructural development in detachment folds: an example from West Virginia. Journal of Structural Geology. Vol.94, P.473-488.
Engelder, T., Gross, M. R. , Pinkerton, P.,1997- An analysis of joint development in thick sandstone beds of the Elk Basin Anticline, Montana, Wyoming. Rocky Mountain Association OF Geologists 1997 Guidebook, Denver, Colorado, P.1-18.
Erickson, S. G., Strayer, L. M. & Suppe, J., 2001- Initiation and reactivation of faults during movement over a thrust-fault ramp: numerical mechanical models. Journal of Structural Geology, Vol.23, P.11-23.
Erslev, E. A., 1991- Trishear fault-propagation folding. Geology, Vol.19, P.617-620.
Fischer, M. P. & Christensen, R. D., 2004- Insights into the growth of basement uplifts deduced from a study of fracture systems in the SanRafel Monocline, East Central Utah. Tectonics, Vol.23, P.1029-1037.
Fischer, M. P. & Wilkerson, M. S., 2000- Predicting the orientation of joints from fold shape: results of pseudo-three-dimensional modeling and curvature analysis. Geology, Vol.14, P.451-460.
Friedman, M., 1969- Structural analysis of fractures in cores from the Saticoy Field, Ventura Co., California. American Association Petroleum Geologists Bulletin, Vol.53, P.367-389
Guiton, M., Leroy, Y. & Sassi, W., 2003- Activation of diffuse discontinuities and folding of the sedimentary layers. Journal of Geophysical Research, Vol. 108, P.80-84.
Guzzeta, G., 1984- Kinematics of stylolite formation and physics of pressure solution process. Tectonophysics, Vol.101, P.383-394.
Halsey, J. H. & Corrigan, A. F., 1977- Fracture study. Report of the fracture study team. Progress report. National Iranian Oil Company (Unpublished).
Hancock, P. L., 1985- Brittle microtectonics; Principles and Practice. Journal of Structural Geology, Vol.7, P.437-457.
Hennings, P. H., Olson, J. E. & Thopson, L. B., 2000- Combining outcrop data and three-dimensional structural models to characterize fractured reservoirs, an example from Wyoming. American Association Petroleum Geologists Bulletin, Vol.84, P.830-849.
James, G. S. & Wynd, J. G., 1965- Stratigraphic nomenclature of Iranian Oil Consortium Agreement Area. American Association of Petroleum Geologists Bulletin, Vol.49, P.2182-2245.
Jamison, W. J., 1987- Geometric analysis of fold development in over thrust tectonics. Journal of Structural Geology, Vol.9, P.207-219.
Johnson, K.  M. & Johnson, A. M., 2002- Mechanical analysis of the geometry of forced-folds. Journal of Structural Geology, Vol.24 , P.401-410
Julian, F.E. & Wiltschko, D.V., 1983- Deformation mechanism in a termination thrust anticline. Geological Society of America, Program with Abstract, Vol. 15, P.606-620.
Logan, B. W. & Semeniuk, V., 1976- Dynamic metamorphism processes and products in Devonian carbonate rocks, Canning BasinWestern Australia. Geological Society of Australia, Special Publication, Vol.6, P.11-68.
McConnell, D. A., 1994- Fixed-hinge, basement-involved fault-propagation folds, Wyoming. Geological Society of America Bulletin, Vol.106, P.1583-1593.
McQuillan, H., 1974- Fracture patterns on Kuh-e-Asmari Anticline, Southwest Iran. American Association Petroleum Geologists Bulletin, Vol.58, P.236-245.
Mitra, S., 1990- Fault-propagation folds: geometry, kinematic evolution and hydrocarbon traps. American Association Petroleum Geologists Bulletin, Vol.74, P.921-945.
Moores, E.  M. & Twiss, R.  J. , 1995- Tectonics. W. H. Freedman & Co., New York, 415pp.
Monaco, C. & De Guidi, G. , 2006- Structural evidence for Neogene rotations in the eastern Sicilian fold and thrust belt. Journal of Structural Geology, Vol.28, P.561-574.
Nickelsen, R. P., 1979- Sequence of structural stages of the Alleghany Orogeny at the Bear Valley Strip Mine, Shamokin, Pennsylvania. American Journal of Science, Vol.279,  P.225-271.
Nino, F. , Philip, H. & Chery, J. , 1998- The role of bed-parallel slip in the formation of blind thrust faults. Journal of Structural Geology, Vol.20, P.503-516.
N.I.O.C. , 1969-  Geological map of south-west Iran: covering the agreement area of Iranian Oil Operation Companies, Scale 1:100 000, National Iranian Oil Company.
Odonne, F. , Lezin, C. , Massonnat, G. & Escadeillas, G. , 2007- The relationship between joint aperture, spacing distribution, vertical dimension and carbonate stratification: An example from the Kimmeridgian limestones of Pointe-du-Chay (France). Journal of Structural Geology, Vol.20, P1-13.
Pattinson, R. & Takin, M., 1971- Geological significance of the Dezful Embayment boundaries. National Iranian Oil Company (unpublished).
Price, N., 1966- Fault and Joint Development in Brittle and Semi-brittle Rock. Pergamon Press, Oxford, 176pp.
Price, N. J. & Cosgrove, J. W., 1990- Analysis of Geological Structural. CambridgeUniversity Press, Cambridge, 502pp.
Ramsay, J. G. & Huber, M. I., 1987- The Techniques of Modern Structural Geology, Vol.1: Strain Analysis. Academic Press, London, 307pp.
Richard, P. & Krantz, R. W., 1991- Experiments on fault reactivations in strike-slip mode. Tectonophysics, Vol.188, P.117-131.
Richard, P., Mocquet, B. & Cobbold, P. R., 1991- Experiments on simultaneous faulting and folding above a basement wrench fault. Tectonics, Vol.188, P.133-141.
Sattarzadeh, Y. , Cosgrove, J. W. & Vita-Finzi, C., 2000- The interplay of faulting and folding the evolution of the Zagros deformation Belt. In: Cosgrove, J. W. & Ameen, M. S. (eds.), Forced folds and Fractures. Geological Society of London, Vol.169, P.187-196.
Savage, H. M. & Cooke, M. L., 2004- The effect of non-parallel thrust fault interaction on fold pattern. Journal of Structural Geology, Vol.26, P.905-917.
Sengupta, S. & Koyi, H. A., 2001- Modifications of early lineations during later folding in simple shear, In: Koyi, H. A. & Mandktelow, M. S. (eds.), Tectonic Modeling: A Volume in Honor of Hans Ramberg: Boulder, Colorado. Geological Society of America, Memoir, Vol.193, P.51-68.
Silliphant, L. J. , Englder, T. & Gross, M. R., 2002- The state of stress in the limb of the split Mountain Anticline, Utah: Constraints placed by transected joints. Journal of Structural Geology, Vol.24, P.155-172.
Simmons, S. P. & Scholle, P. A., 1990- Late Paleozoic uplift and sedimentation, Northeas Bighorn Basin, Wyoming, Wyoming Geological Association, Guidebook, Vol.41, P.39-55.
Stanton, H. I. & Erslev, E. A., 2004- Sheep Mountain Anticline: backlimb tightening and sequential deformation in the Bighorn Basin, Wyoming. Wyoming Geological Association Guidebook, Vol.53, P.75-87.
Stearns, D. W., 1968- Certain aspects of fractures in naturally deformed rocks. Rock mechanics Seminar. R. E. Riecher, Bedford, Terrestrial Sciences Laboratory, P.97-118.
Stearns, D. W. & Friedman, M., 1972- Reservoirs in fractured rocks. American Association of Petroleum Geologists Bulletin, Memoir, Vol.16, P.82-100.
Suppe, J., 1985- Principles of Structural Geology. Prentice Hall, Englewood cliff, New Jersey, 537pp.
Talbot, C. J. & Alavi, M., 1996- The past of a future syntaxis across the Zagros, In: Alsop, G. I., Blundell, D. J. & Davison, I. (eds.), 1996. Salt tectonics. Geological Society Special Publication, No. 100, P.89-109.
Twerenbold, E. F. , Raualx, S. J. & Van Os, B., 1962- Fracture pattern study of Kuh-e-Bangestan and its bearing on oil accumulation. National Iranian Oil Company (Unpublished).
Twiss, R. J. & Moores, E. M., 1992- Structural Geology. W. H. Freedman & Co., New York, 532pp.
Wallace, W. K. & Homza, T. X., 2004- Detachment folds versus fault-propagation folds and their truncation by thrust faults. In: McClaly, K. R. (ed.), Thrust Tectonics and hydrocarbon systems. American Association of Petroleum Geologists Bulletin, Memoir, Vol.82, P.324-355.
Walsh, J J. , Nicol, A. & Childs, G., 2003- An alternative model for the growth of faults. Journal of Structural Geology, Vol.24, P.1669-1675.
Ye, H. , Rotden, L. , Burchfiel, C. & Schuepbach, M., 1996- Late Paleozoic deformation of interior North America: The Greater Ancestral, Rocky Mountains. American Association Petroleum Geologists Bulletin, Vol.80, P.1397-1432.