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Basement-involved fault geometry and kinematics has a systematic effect on the structural style of the tectonic setting. In this study, 2D and 3D seismic datasets, well data as well as thickness and depth maps were utilized to consider and reconstruct the characteristics and effects of the wrench-dominated basement-involved fault underlying the Bahregansar anticline, which is a gentle, elongated and NW–SE-trending structure in the NW Persian Gulf, on the nature of its folded strata. Moreover, using the 2D sequential restoration, the deformation of the basement structural features was modelled and analysed for its influence on the reactivation of faulting. The results show that the major basement-involved fault, called the Hendijan–Bahregansar–Nowrooz Fault (HBNF), extends along the NE–SW-trending orientation and consist of several key anticlines. The structural evolution of the Bahregansar anticline has been deeply affected by Turonian folding phase and Pliocene Zagros orogeny associated with the HBNF. In the Upper Cretaceous, the HBNF propagated upward through the overlying sedimentary sequences when the inherited normal fault contractionally reactivated in the sinistral-reverse sense as the transpression zone in response to the Neo-Tethys oceanic plate subduction under the Eurasian plate. In this regard, the NNE–SSW-trending Bahregansar anticline (i.e., Arabian trend) formed as a forced fold. Continuing oblique convergence and associated deformation was accommodated by a change in the HBNF displacement sense from sinistral to dextral movement and buckling of the Bahregansar anticline as a result of the Pliocene Zagros orogeny.

We explored the influence of a variety of geometric and mechanical factors in the evolution of décollement folds above a weak décollement level in a sedimentary sequence. Under an applied overburden pressure, we construct nine discrete element models (DE-models) to test the effects of mechanical stratigraphy, the thickness of the décollement layer, and the number of strong and weak layers within the sedimentary cover sequence. The effects of the aforementioned parameters on the structural style of fold belts and the mechanical evolution of décollement folds that develop during a progressive deformation are what we are searching for. The one-way lateral motion of a rigid, vertical boundary wall was used to shorten the particle assemblage. The models presented in this study were then compared to a natural structure in Iran and demonstrated that the combined effects of mechanical behaviour, the thickness of décollement layer, and the number of strong and weak layers within the sedimentary cover sequence are playing the decisive role in the structural style, kinematic and mechanical evolution of décollement folds.

In this research, the effect of nanoclay addition on mechanical strengths of cement mortars subjected to elevated temperatures was investigated. Mortars with three different replacement dose of montmorillonite nanoclay (0, 1 and 2% of cement weight) were prepared and then subjected to 200 °C, 400 °C, and 600 °C for 2 hrs. Compressive and flexural strengths of the heated and unheated specimens were obtained. The results showed that nanoclay addition to cement mortar caused marginal enhancement in its compressive and flexural strengths at room temperature. But, the efficiency of nanoclay to enhance the flexural strength of cement mortar increased at higher temperatures. The maximum relative improvement in flexural strength due to 2% nanoclay addition was achieved at 400°C.