Kinematic indicators in Riphean carbonate rocks of the Siberian Platform Western framing (on the example of the Alad’inskaya Formation)

Abstract

Introduction. New data on the structure of sections of the Middle Riphean Alad’inskaya Formation at the Kamenskaya subzone of the Yenisei Range (r. Irkineeva) were obtained. These sections indicate the tectonic nature of brecciated and banded dolomite varieties with the associated areas of cavern development, representing promising objects of oil and gas exploration works.Aim. To substantiate the tectonic nature and structural confinement of cavern development areas in dolomites of the Alad’inskaya Formation.Materials and methods. The sections of Alad’inskaya Formation carbonates, located along the Irkineeva river, were studied, including determination of the sample phase composition by the X-ray diffraction method (ARL X’TRA) and examination of samples in sections (Leica DMLR) and by a scanning electron microscope (TESCAN VEGA 3 LMH). Kinematic indicators were studied and classified; a model of structural formation in carbonate rocks was substantiated.Results. A detailed layer-wise description of the studied section, illustrated by various-scale images, was carried out. The kinematic indicators of specified rocks with a reference to a particular section were revealed, described and systematized. A conclusion is made about the genetic association of dolomite breccia, banded dolomites, and cavern development areas with a local thrust, observed at the base of the studied section.Conclusion. The tectonic nature of brecciated and banded dolomites of the Alad’inskaya Formation and the structural control of cavern development areas are substantiated. As a result, the model of structural formation in lamellar carbonates under longitudinal compression is verified.