IMPLICATIONS OF OUTCROP GEOLOGY FOR RESERVOIRS IN THE NEOGENE PRODUCTIVE SERIES - APSHERON PENINSULA, AZERBAIJAN

The Neogene sediments of eastern Azerbaijan and western Turkmenistan c ontain significant hydrocarbon reserves in deltaic reservoirs. Sedimen tary logging of these reservoirs at outcrop in Azerbaijan has outlined four facies associations that encompass a range of paleoenvironments, from alluvial braided river sandstones and conglomerates to delta-fro nt siltstones and mudstones. The facies associations suggest a river-d ominated braid delta and are arranged into an architecture controlled by base-level changes: parasequences, parasequence sets, and sequence boundaries are key elements, The facies associations and stratigraphic architecture, together with outcrop observations of cementation and f aulting, are summarized in terms of four idealized reservoir models: f luvial, delta plain, proximal delta front, and distal delta front, Eac h reservoir model has distinctive grain-size and shale distributions, Comparison of nearby oil fields with the studied outcrops suggests tha t the outcrops form good analogs from which to model reservoir archite cture, barriers and baffles to fluid flow, reservoir heterogeneity, an d reservoir quality variations.