The stratigraphy of the Lurestan Arc preserves the geologic formation of the northeastern Arabian margins from the Paleozoic rifting that led to the opening of the Mesozoic Neote-Thys Ocean, the final closure of the ocean, and the beginning of the collision of the continent with the Central Iranian Plateau in the late Eocene (Alavi, 2004). The Lurestan arc has cover thicknesses of ∼6-10 km (Blanc et al., 2003; Homke et al., 2009; McQuarrie, 2004; Sadeghi and Yassaghi, 2016; Vergés et al., 2011b). in contrast, the Mesopotamian foreland SW of the arc has cover thicknesses of ∼11-14 km.( Sadeghi and Yassaghi 2016; Blanc et al., 2003; Casciello et al, 2009; Sherkati et al., 2006; Farzipour-Saein et al. 2009;Emami et al., 2010;Farzipour-Saein et al., 2009 ).
The main causes of the difference are usually attributed to vertical offset and exhumation across two major basement-cored reverse faults. The Mountain Front Fault, which marks the frontal outcrop of Oligocene-Miocene Asmari limestone in the region, and the Zagros Foredeep Fault, which runs along the foreland deformation front (Berberian, 1995); Figure 2). As opposed to the Fars arc, there is no clear evidence of basal Infra Cambrian Hormuz salt deposits in the northwest SFB (Kent, 1979; Edgell, 1991). Nonetheless, mechanical study indicates that the Lurestan arc has the same decoupling horizon, allowing the deformation front to proceed southwest across the Arabian plate (McQuarrie, 2004). The Mesozoic strata of the Lurestan Arc differ from those in other areas of the Iranian Zagros in that they contain more pelagic shales and fewer neritic limestones (Casciello et al., 2009; Sepehr et al., 2006). There are three main detachment-forming horizons in the Lurestan cover sequence, and each one leads to folds with distinct wavelengths. (Casciello et al., 2009; Farzipour-Saein et al., 2009; Vergés et al., 2011a). "Whalebacks" are produced by surface anticlines oriented NW-SE in the Cretaceous Bangestan Group's resistant limestones and the Oligocene to Miocene Shahbazan-Asmari formations. Conversely, synclines generally show Aghajary and Bakhtyari sandstones and conglomerates, as well as Gachsaran evaporites of the Pliocene age. Figure 13 also provides a deeper insight into the geological map.
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