Lithofacial characteristics of the miocene sediments of the tarsdallar area

Abstract

In the article, the analysis of the lithofacies characteristics of the Miocene sediments of the Tarsdallar area was considered. For this purpose, a 3D geological model of Miocene-aged rocks was compiled using the Petrel program, based on the data obtained from the petrophysical and geophysical studies of wells in the Tarsdallar area. As a result, this model allowed spatial monitoring of the litholofacies changes of the Miocene sediments in the area. Thus, it was determined that the Tarkhan-Chokrak sediments consist mainly of clay-siltstone rocks, and in the central and southern parts, sandy-siltstone rocks, and the thickness increases from 177 to 442 m from northwest to southeast. Middle Miocene Konkh-Karagan sediments are followed by an increase in sandiness in the Northeast of the study area. The thickness ranges from 106 to 307 m. In the east, it was determined that the thickness increased. A sharp change in geological conditions and expansion of the basin occurred in the Sarmatian bed, the sedimentary complex with the largest thickness among these three layers of the Miocene division. The main part of reservoir rocks belongs to these sediments. Siltstones and sandstones dominate mainly in the central part of the structure. As can be seen from the texture, in the Miocene deposits, sandy-siltstone rock is mainly collected in the main parts of the structure.