A reservoir model for the main Pliocene reservoirs of the Bahar Field in the Caspian Sea, Azerbaijan

Abstract

In this paper the results of a reservoir evaluation study of the Bahar Field, one of the most important oil and gas fields in the Azerbaijanian sector of the Caspian Sea are presented. The study has concentrated on the most important reservoir sections, Balakhany X and Pereriv Suite, encompassing (i) sedimentological and stratigraphic interpretation, (ii) petrophysical analysis, (iii) structural interpretation, (iv) assessment of hydrocarbon distribution, (v) geochemical characterization of the hydrocarbons, (vi) assessment of reservoir compartmentalization, (vii) establishment of static and dynamic reservoir models in digital format, as a basis for calculating in-place resources and assessing the potential for improved oil recovery. The study has provided new and detailed insight into the reservoir architecture and properties of the Bahar Field. In a broader context this detailed information and data analysis is believed to provide an improved basis for evaluating other tested and untested structures in this prolific hydrocarbon province.

Sedimentation in a discharge dominated fluvial-lacustrine system: the Neogene Productive Series of the South Caspian Basin, Azerbaijan

“…Previous workers may have over-estimated the role played by deltaic processes in the deposition of the Productive Series outcrop (Reynolds et al, 1998;Abdullaev et al, 1998). Those authors viewed the alternation between sand-prone and mud-rich suites as the product of repeated progradation and retrogradation of a deltaic complex in response to fluctuating lake-level.…”

“…Jones and Simmons (1996) tentatively correlate basin isolation and base level lowering in the South Caspian Basin to the 5.5 Ma late Messinian isolation of the Mediterranean Sea. As a result, major river systems such as the palaeo-Volga and palaeoAmu Darya were focused into the South Caspian Basin, resulting in deposition of the Productive Series, which accumulated to a thickness of between 5 and 7 km in the basin interior (Abrams & Narimanov, 1997;Abdullaev et al, 1998). Thicknesses across the Apsheron Peninsula and along the Apsheron Sill are lower, in the order of 1.5 km.…”

Correlation, alteration, and origin of hydrocarbons in the GCA, Bahar, and Gum Adasi fields, western South Caspian Basin: geochemical and multivariate statistical assessments

“…They proposed that the oils were sourced from Eocene and older units, and perhaps partially from the shales of the Maikop Formation. Abdullaev et al (1998) reported that the Bahar field oils present similar attributes with the major oil group as described by Abrams and Narimanov (1997). However, Abdullaev et al (1998) also pointed out that the Bahar field oils are waxier, have more C 29 steranes and less C 30 steranes than the major oil group described by Abrams and Narimanov (1997).…”

“…Abdullaev et al (1998) reported that the Bahar field oils present similar attributes with the major oil group as described by Abrams and Narimanov (1997). However, Abdullaev et al (1998) also pointed out that the Bahar field oils are waxier, have more C 29 steranes and less C 30 steranes than the major oil group described by Abrams and Narimanov (1997). A very small carbon isotopic range with heavy character (d 13 C ¼ 2 25.0 to 2 24.6 per mil) within the Bahar oils was attributed to a common source, possibly Upper Maikop Formation or Diatom Suite.…”

Predicting the impact of sedimentological heterogeneity on gas–oil and water–oil displacements: fluvio-deltaic Pereriv Suite Reservoir, Azeri–Chirag–Gunashli Oilfield, South Caspian Basin

“…2A). Fluctuating lake levels resulted in multiple, high-frequency cycles of advance and retreat of the palaeo-Volga Delta across a low-gradient, basin-margin ramp; these cycles are reflected in a strongly layered stratigraphy in which sandstone-bearing intervals alternate with laterally extensive mudstones (Abdullaev et al 1998;Reynolds et al 1998;Hinds et al 2004;Kroonenberg et al 2005; Fig. 2B).…”