TECTONIC ANALYSIS OF AKTOBE AND ZHANKORGAN VALLEYS OF THE BOLSHOI KARATAU CARBONATE PLATFORM

Abstract

Bolshoi Karatau Mountains in the south of Kazakhstan expose a Devonian-Carboniferous carbonate platform exposing several formations which exhibit some strong patterns of multiphase heavy deformations. Aim of this study is to analyse valley-scale details of Aktobe and Zhankorgan sections of the Bolshoi Karatau mountains, including folds, veins, and formations and how they connect between the valleys. The results are expected to shed light on the tectonic overprints on the carbonate platform and the overall deformation features on the region. So far 7 formations have been mapped all dipping southwest as part of the northern limb of a big synclinal structure while a smaller portion of the formations comprise the southern limb. Cross-sections reveal substantial folding events in the middle of the valley that are positioned at ad angle in relation to the strike-slip fault proposed by Alexeiv et al. (2009). Findings in this paper reveal a higher lateral connection between formations and structures and hence propose an emphasized study of the same formations of the same northwestern limb of the big syncline across the two valleys. Comparatively, the connection between two limbs of the big syncline at the Aktobe valley is poorly understood due to strike-slip faulting that cuts across the big syncline