Introduction
The Øygarden Fault Complex (ØFC) is a basement-involved structural element that marks a major change in crustal thickness in the eastern-most part of the northern North Sea. The fault complex strikes approximately north-south, extends well over 100 km and exhibits lateral (along-strike) structural variations from the Horda Platform in the north to the Stord Basin in the south. It marked the eastern extent of major activity in the North Sea during two Mesozoic rift events (Permo-Triassic and Jurassic-Cretaceous).
The post-rift evolution of the ØFC, especially during the Neogene, is less well constrained. Moreover, the fault complex is the eastern boundary of the greater Smeaheia fault block (Fig.1) which has been identified as a potential CO2 storage area where prospective Jurassic storage formations may, in places, be juxtaposed against basement rocks across the ØFC. Further, there is evidence that the fault complex is tectonically active in places.
Aims
- Undertake a regional structural analysis (Horda Platform to Stord Basin) of the ØFC in order to establish along-strike variations in the hanging wall of the structure, discern the present-day geometry, evolution history and implications for the Neogene-present tectonic history.
- Identify and characterize if additional closures (other than Beta) are present in sand-prone formations within the Jurassic, and potentially within the Triassic.
- Identify any areas (including in the Beta closure) where prospective CO2 columns would juxtapose with Basement across the ØFC (Juxtaposition analysis). (Optional) Compute shale-gouge ratio for the ØFC and attempt to calibrate results by synthesizing permeability information on crystalline rocks from literature.
- Undertake reactivation analysis in order to determine fault integrity.
Objectives
- Depth converts available seismic data utilizing a newly generated velocity model (Fig. 1).
- Seismic interpretation of several sections crossing the ØFC, from the Horda Platform to the Stord Basin.
- Generate a high-resolution 3D geomodel of the ØFC from seismic interpretation.
- Discern if additional trapping structures (other than Beta) exist in the hanging wall of the ØFC. If so, characterise and discern volumetric capacity.
- Generate and visualise comprehensive fault displacement and attributes (e.g. strike, dip, curvature) analyses in order to inform fault complexity and segmentation history.
- Conduct cross-fault juxtaposition analysis.
- (Optional) Estimate seal/baffle capacity of the ØFC using shale-gouge algorithms.
- Assess the reactivation potential of the ØFC along strike.
Data
The project will utilize both 2D regional seismic data, select 3D surveys and well-log data (Figure 1). Reactivation parameters will be synthesized from literature and industry reports.
Click her for a bigger version of the picture.
Tools and Method
Initial seismic interpretation will be conducted using Schlumberger Petrel E&P software platform. Fault models will be exported to Petex Move and/or Badley’s T7 for analysis (e.g., juxtaposition, shale-gouge, restoration and reactivation).
Learning outcomes
Proficiency using Schumberger Petrel E&P Software Platform and Petex Move/Badley’s T7. In-depth knowledge of fault-analysis. Independent research, academic writing and presentation skills.
Additional details
This project is affiliated with Task 9 of the NCCS centre, international research cooperation on CO2 capture, transport and storage (CCS). The project is also run in conjunction with Equinor.
Contact Details
For further information or to register interest in projects, please contact Mark Mulrooney (mark.mulrooney@geo.uio.no).