Dislocations of lateral compression in the Permo-Triassic additional plate complex and the platform cover of the Buzachi Peninsula (west of the Turan plate)

Abstract

Relevance of the work. Up to now, the prevailing point of view is about the decisive role of vertical tectonic movements in the formation of the structure of platforms, including the anticline folds of their cover. In addition to the theoretical, this issue is also of practical importance, since the latter often contain accumulations of oil and gas. In recent years, there has been more and more evidence of the presence of dislocations in the cover of platforms formed under the influence of lateral compression forces. One of these areas is the Buzachinsky vault, located in the western part of the Turan plate. Studying the structural features of the folds and ruptures developed here will solve the problem of the mechanism of their formation and make a step forward in understanding the genesis of intraplate dislocations. The purpose of the research. To study the morphology of folded and discontinuous disorders in the pre-plate complex and platform cover of the Buzachinsky arch in order to determine their morphology and conditions of formation. Research methods. Comprehensive analysis of geological and geophysical information, including materials of seismic exploration, deep drilling, geological survey. The interpretation of time sections was made in order to determine the morphology of dislocations. The materials of structural drilling, oil exploration wells, as well as geological survey are analyzed. If necessary, structural constructions were carried out with the involvement of seismic data. Core material, paleontological definitions were studied, correlation of well sections was performed. In order to restore the history of the development of the territory as a whole and the local uplifts complicating it, paleotectonic constructions were made. Methods of seismostratigraphy and structural analysis are applied. Results. The conducted studies indicate the determining role of tangential compression in the formation of the structure of the pre-plate Permo-Triassic complex, as well as overlapping platform deposits. The morphology of specific fold-thrust dislocations is described. The established patterns in the structure and areal distribution of dislocations make it possible not only to better understand the mechanism of their formation, but also to solve purely practical problems, since large accumulations of hydrocarbons are concentrated in them. The obtained results can be used in the study of the geological structure of other less studied areas of the young platform, as well as contribute to the selection of rational methods of geological exploration for oil and gas.