Reservoir heterogeneity of the Garzan Formation by using sedimentological, micropaleontological, geophysical, and geochemical analyses, Batman and Siirt, Southeast Türkiye

2024-1-15
Altıntaş, Damla
The sedimentary architecture of depositional environment, diagenetic history, and geochemical model of the Garzan Formation were built by the use of thin section analysis of well cuttings, cores and logs, three-dimensional seismic data, field observations, and geochemical data. In this research, the Garzan Formation is divided into twenty two microfacies deposited in inner ramp, mid-ramp, outer ramp, and basin facies zones on a distally steepened carbonate ramp. The main diagenetic processes, which influenced the Garzan strata, are determined as micritization, neomorphism, dissolution, cementation, compaction, and partial dolomitization. The sedimentological facies are correlated with the seismic facies defined on the spectral decomposition map generated from three dimensional seismic data. This study revealed that different colored seismic facies are ascribed to different sedimentological facies zones of the Garzan successions. The channel-like features observed on top of the unit on the seismic attribute maps are characterized as tidal channels influenced by the bottom currents. The micropaleontological analysis was conducted by the classification of macrofossils, benthic and planktic foraminifera on the samples collected from the outcrop of the Garzan carbonates. Calcareous nannopaleontology was carried out on the samples of the measured section and the core piece. The benthic foraminifera classification shows that the unit deposited in the Maastrichtian. The planktic foraminifera and nannofossil biozonation point out the late Maastrichtian age. The geochemical analyses such as stable carbon and oxygen isotopes, XRF, XRD, SEM, and CT scanning were performed to decipher the nature of the irregular contact between the Garzan and overlying Germav formations in Well E. This study reveals that a small scale karstification occurred before the deepening of the carbonate platform.
Citation Formats
D. Altıntaş, “Reservoir heterogeneity of the Garzan Formation by using sedimentological, micropaleontological, geophysical, and geochemical analyses, Batman and Siirt, Southeast Türkiye,” Ph.D. - Doctoral Program, Middle East Technical University, 2024.