AUTHORS: F.Arboit, R.Di Cuia, A.Riva, R.Bitonte
“HYDROCARBON EXPLORATION IN THE ZAGROS MOUNTAINS OF IRAQI KURDISTAN AND IRAN” Conference, Geological Society of UK, London
In the last 10 years, the northern part of Iraq have received a constantly increasing attention of oil companies interested in new frontiers for hydrocarbon exploration in are region where the presence of hydrocarbons is confirmed by proved plays and abundant oil seeps.
Most of the Iraqi reserves are and have been produced from the “foothill zone” and the new exploration has moved into the “high-folded zone” of the Zagros thrust belt. In this domain of the Iraqi Zagros range most of the oil and gas discoveries lie into carbonate rocks reservoirs, such as the Cretaceous Qamchuqa Shiranish, Hartha and Kometan formations (all important carbonate fractured reservoirs), and the Teriary Fatha (Lower Fars) Formation (limestone dominated unit), the Jurassic Sargelu and Butmah formations and the Triassic Kurra Chine formations.
Matrix porosity in this complex carbonate reservoirs is very low and the main oil accumulations are within the open fault and fracture network. For this reason a complete understanding of the structural framework and of the evolution of the stress field with time is fundamental to predict the faults and fractures network distribution, the potential hydrocarbon accumulations and the potential deliverability characteristics of the different units and structures.
This study analysed the characteristics and the evolution with time of the structural framework of the of the High Folded Zone in northern Iraq and described the structural styles across the Iraqi Zagros. The interpretation is based mainly on a structural analysis made through remote sensing techniques with the integration of geological and geophysical subsurface data, stratigraphy, tectonic published information and present day stress field measurements.
The main results of the study are the structural description and characterization of 29 structures in the high folded zone of the Iraqi Zagros and the possibility to propose a model that relates the structural style of the structures, the Zagros stress field and the present day stress field with the exploration results in the area.