Petrophysical Evaluation of Cretaceous System Sediments in Amu Darya Basin

Abstract

The Mesozoic era represents a critical period for the formation and accumulation of global hydrocarbon resources due to favorable geological and geochemical conditions. This study investigates the geological and geochemical controls on hydrocarbon generation, migration, and accumulation, with a particular focus on Cretaceous petroleum systems. The objective is to evaluate source rock quality and reservoir properties using an integrated dataset and multidisciplinary analytical approach. The methodology combines geological interpretation, geochemical characterization, and reservoir engineering analysis. Well data were utilized to assess key petrophysical properties, including porosity, permeability, and water saturation. In addition, geochemical parameters such as total organic content, organic matter type, thermal maturity, and kerogen classification were analyzed to determine hydrocarbon generation potential and maturation level. Structural and stratigraphic frameworks were also considered to evaluate migration pathways and trapping mechanisms. The results indicate that Cretaceous sequences are characterized by high-quality source rocks with predominantly oil-prone kerogen types and sufficient thermal maturity for effective hydrocarbon generation. Reservoir intervals exhibit favorable petrophysical characteristics, including adequate porosity and permeability, which enhance storage capacity and fluid flow efficiency. Furthermore, the presence of well-developed structural and stratigraphic traps contributes to efficient hydrocarbon accumulation and preservation. The integration of geochemical maturity indicators with reservoir quality assessment demonstrates a strong correlation between source rock richness and effective petroleum system development. Overall, the findings confirm that Cretaceous petroleum systems provide highly prospective conditions for hydrocarbon exploration. The study highlights that a combined geological and geochemical evaluation approach is essential for accurately characterizing petroleum systems and improving exploration success in sedimentary basins.