SOME STRUCTURAL CHARACTERISTICS OF AZMAR ANTICLINE – NE IRAQ

The purpose of this study is to elucidate the structural style of Azmar structure, a major anticlinorium within the imbricate partition of Zagros fold-thrust belt in northeastern Iraq. Structural analysis of this anticlinorium demonstrated that it consists of four main NNW-SSE trending anticlines. They are imbricated SW ward through NE dipping reverse faults merge to a deep-seated detachment. Furthermore, analysis of minor folds on hinge and limbs of the main Azmar anticline revealed the versatile style of such minor folds and their opposing vergencies. These features emphasize the role of faulting in development of the major fold and the minor folds. This interpretation has been supported by hinge angularity, as well as by association of hinge and limb disrupting reverse slip meso-faults with those minor folds. Therefore a progressive fault-related folding is proposed for Azmar structure in this work

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  • Agard, P., Omrani, J., Jolivet, J. and Mouthereau, F., 2005. Convergence history across Zagros (Iran): constraints from collisional and earlier deformation: International Journal of Earth Sciences, 94, 401-419.
  • Alavi, M., 2004. Regional stratigraphy of the Zagros fold-thrust belt of Iran and its proforeland evolution: American Journal of Science, 304, 1-20.
  • Al-Hakary ,S., H. Geometrical analysis and structural evolution of a selected area from NE Zagros Fold Thrust Belt and their tectonic implications, Northeast Iraq region, NE Iraq. Ph. D. Thesis, Sulaimani University in press.
  • Fluety, M.J., 1964. The description of folds: Geological Association Proceeding, 75/ 4, 461-492.
  • Hobbs, B.,E. Means, W.D. and Williams, P.F., 1976. An outline of structural geology: John Wiley and Sons, New York, 571 p.
  • Ibrahim, A.O., 2009. Tectonic style and evolution of the NW segment of the Zagros fold- thrust belt, Sulaimani governorate, Northeast Iraq region, NE Iraq: Unpublished Ph. D Thesis, Sulaimani University.
  • Ragan, D.M., 1986. Structural geology; an introduction to geometrical techniques: John Wiley and Sons, Inc., 196 p.
  • Ramsay, J.G. and Huber, M.I., 1987. Folds and fractures: The techniques of modern structural geology: 2, Academic Press, New York, 700 p.
  • Suppe, J., 1985. Principles of structural geology: Prentice-Hall, Inc., New Jersey, 537 p.
  • Talebian, M. and Jackson, J., 2002. Offset on the main recent fault of NW Iran and implications for the late Cenozoic tectonics of the Arabia-Eurasia collision zone: Geophysical Journal International, 150, 422-439.
  • Twiss, R.J. and Moores, E.M., 2007. Structural geology: W.H. Freeman and Company, 41 Madison Avenue, New York, 736 p.
  • Van der Pluijm, B.A. and Marshak, S., 1997. Earth structure: An introduction to structural geology and tectonics: WCB/McGraw-Hill, USA, 495 p.