Sedimentological and Petrophysical Study of the lower Triassic Series of Boukhellala Deposits, Oued Mya Basin

Abstract

This study characterizes the Triassic reservoirs in the Hassi Boukhellala area of the Oued Mya basin in Algeria. The basin sits on a Precambrian basement and contains Paleozoic sedimentary rocks with potential hydrocarbon reservoirs in Triassic sandstones. The study focuses on the sedimentology and petrophysical properties of these reservoirs (T1 and T2 series) to understand their potential for oil and gas production. Sedimentological analysis reveals a fluvial depositional environment with cyclical patterns of coarse-grained sandstones and conglomerates at lower levels transitioning to finer-grained sandstones with clay layers at higher levels. This suggests changes in energy and sediment supply to the river system over time. In addition, trough cross-bedding indicates a braided river system with dynamic flow conditions. The presence of alluvial plain and fan deposits suggests a complex depositional landscape influenced by variations in climate and sediment supply. Petrophysical analysis shows good porosity and permeability values in the southeastern and northeastern parts of the study area, particularly in wells P3 and P4. Conversely, these values are lower in the northwestern holes (P1, P2 and P5). This distribution correlates with depositional facies, highlighting the link between reservoir quality and sedimentary processes. The study highlights the importance of understanding this relationship for effective reservoir characterization and hydrocarbon exploration. Overall, the study provides valuable insights into the sedimentological and petrophysical properties of the Triassic reservoirs in the Hassi Boukhellala region. This information is crucial for assessing their potential for hydrocarbon production and for optimizing exploration strategies in the Oued Mya basin