Slip partitioning and inclined transpression in the Bazargan fold and thrust belt, Central Iran Microcontinent, Kerman area, SE Iran

Abstract

Inclined transpression can be defined in terms of simultaneous contraction and strike-slip and dip-slip shearing. An example of an upper-crustal inclined transpression zone is exposed at Bazargan area, SE Iran. As with most natural transpression zones, deformation at Bazargan area is heterogeneous, and widespread kinematic strain partitioning has given rise to an irregular distribution of strain components and resulting structures. Based on structural and strati graphical evidence, deformational events are divided into two stages: (1) a Late Triassic event and (2) a Late Cretaceous to Miocene event. A wide range of known structures at the map and outcrop scales show the effect of slip partitioning on the structural evolution of this area during this period. The dynamic analysis based on folds, fault striations and calcite twin data show a NNE-SSW trend for the compressive axes in this area. The results of dynamic analysis reveal that the orientation of the compressive axes did not change during late Triassic to present. Moreover, they show that the structural evolution of the Bazargan area occurred under the effect of continues deformation phases which is related to contraction, dip slip and strike slip component. Furthermore, the results indicate that the evolution of Bazargan area in the south of Tabas block is compatible with an inclined transpression model.