The South Caspian Basin (SCB) is the region dominated with abundant petroleum resources mainly in shallow-marine, deltaic to lacustrine deposits of middle Pliocene age in depth ranging from 2500 to 3500 m (called as “Productive Series”). So, oil and gas production has played an important commercial role in this region for more than 150 years. The exploration activities in Iranian portion of SCB was proceeding to drilling of two successful wells in 2012 and 2014 on one of the important structures now known as Sardar-Jangal Field.
In continuation of exploration activity in this deep-sea environment, a research project with title of “Detection of Geohazards and Prospective Hydrocarbon Sweet-spots in the Caspian Sea Using Geophysical and Geological Methods and Reservoir Information” was planned to be conducted in the Iranian portion of central offshore of SCB. The study area was extended to 4110 square kilometers covered by four separated 3D marine seismic blocks connected with sparse 2D seismic lines. Khazar Exploration and Production Company (KEPCO) as a subsidiary of National Iranian Oil Company (NIOC) awarded this project to Dana Energy. The comprehensive study had been started on December 23, 2019 and successfully finished on March 8, 2022 with special focus on the ultimate goals summarized as below:
- Qualitative / quantitative assessment and ranking of potential plays and prospects from geophysical and geological points of view,
- Identification and delineation of different types of geohazards, geomorphologies and potential natural gas hydrate to mitigate drilling risks in future exploration and production plans.
In this study, two aforesaid objectives were successfully achieved by Dana Energy’s Geoscientists and Geophysicists through accomplishing the following main phases:
- Seismic and well data conditioning and enhancement
- Seismic interpretation, velocity model building and domain conversion,
- Advance quantitative interpretation based on seismic data (e.g. Amplitude variation versus offset (AVO) and Post- and Pre-stack inversions)
- Advanced rock physics study
- Reservoir properties estimation
- Geological (structural and stratigraphic) studies
- Seismic attributes analysis and integration
- Pore pressure prediction
- Geo-body extraction
- Gas hydrate detection and appraisal
- Quantitative characterization of the conventional reservoirs
- Prospects ranking and related risk assessment
Meanwhile, due to the research-based nature of the project and for the first time in Iran, the following state-of-the-art techniques have been domesticated in Dana Energy as the by-products of the project:
- Establishment of methodologies for automation of time-consuming tasks using new Artificial Intelligent (AI) approaches and deep learning algorithm.
- Application of different seismic processing methods in deep marine area to obtain the best velocity and images by evaluating tomography in Pre-Stack Depth Migration (PSDM) algorithm and Downward Continuation approach
- Analysis of the different ways for pre-drill recognition of Shallow Water Flow (SWF) as a challenging geohazard in deep sea drilling,
- Development of in-house application for Elastic Full Wave Form Inversion (EFWI) in 1D domain
The outcomes of this project reconfirm that Dana Energy as a knowledge-based enterprise can drive the optimum approaches in all aspects and create value for all clients.