Solid bitumen in shales from the Middle to Upper Jurassic Sargelu and Naokelekan Formations of northernmost Iraq: implication for reservoir characterization

Abstract Petrographic, organic, and inorganic geochemical analysis of the solid bitumen host shales from Middle Late Jurassic-age Sargelu Naokelekan Formations Banik section, northernmost Iraq, was undertaken. The aim to understand their derivation preservation, as well examine carbon oxygen isotopes, paleoredox proxies under which sediments were deposited. Petrographic both formations revealed presence high reflectance (first phase) low (second phase). equivalent vitrinite indicates that two probably accumulated within shale reservoirs following oil migration source rocks located same formations. Mineralogical study (XRD SEM - EDX) hosting also contain clay minerals (illite, rectorite, chlorite, montmorillonite, kaolinite) carbonate minerals, quartz, alkali feldspar, pyrite. Carbon isotope data along with indicators suggest sources in formed a shallow-marine setting, most anoxic conditions where water circulation restricted.