Magnetic Expression of Buried and Obscured Anticlines in South America

2. Magnetic Expression of Buried and Obscured Anticlines in South America An HRAM survey flown over a tropical forest in Guatemala reveals the presence of several buried and obscured anticlines only partially visible in radar imagery. The size and geometry of the prospective structures are recognized by the high-frequency magnetic signature of near-surface rock units captured by the low-flying magnetometer.

3. Merging 3D Seismic with HRAM data Example illustrating how HRAM data can be used to extend the mapping of key geological structures in areas that are not covered by the 3D seismic. In this example, the western extension of a major wrench fault system is easily recognized in HRAM data. The cost of HRAM surveys is usually less than 5% of the cost 3D seismic data.

4. Magnetic Expression of Near-Surface Structures in the WCSB Radarsat-1 imagery and HRAM data are used to map near-surface structures in the Canadian Folf Belt region. Such mapping usually leads to the recognition of cross-trending fault and fracture systems generally difficult to recognize with typical exploration tools. Large-scale cross-strike discontinuities (CSD) could exert significant control on the development of oil and gas fields in this region.

5. Magnetic Expression of a Major Shear Zone in the WCSB HRAM survey flown by the Geological Survey of Canada south of the Norman Wells field in the NWT. The HRAM data provides information on the structural geometry of the Gambill Shear Zone and several buried structures in front of the fold belt. Note that many of the structures identified on the magnetic image do not have surface expressions, and therefore not recognized by surface mapping. Two buried structures, circled in yellow (d) ,were initially recognized with HRAM data. These structures were further imaged with seismic data and later tested by a successful exploration well.

6. Magnetic Expression of Salt-Cored Anticlines 3D display of seismic and HRAM data over the Gambill shear Zone. This complex structure is made of a series of salt diapers that intruded the fault zone and lead to the development of near-surface elongated anticlines and synclines. The near-surface expression of the salt-cored anticlines are nicely mapped with the HRAM data, which captures the magnetic expressions of several eroded rock units. This example illustrates how HRAM data and 2D seismic can be used to generate a relatively inexpensive 3D geophysical data sets that, in some cases, can reduce the need for large-scale 3D seismic programs.

7. Near-Surface Structures in Alaska HRAM survey over the remote Fold Belt Region of Alaska is used, in conjunction with available surface geological maps, to produce a detailed interpretation of surface and near-surface structures of this geologically complex area. Seismic data is then used to relate the surface features with subsurface structures. In the example shown here, dip and strike information was extracted from HRAM data using extended Euler deconvolution techniques developed by Mushayandebvu et al. (2001, see our research publications list)

8. Automated Fault Detection in the Green River Basin Extended Euler deconvolution techniques are used to identify the magnetic expressions of faults centered around the Jonah field in the Green River Basin of Wyoming. Magnetic anomalies associated to faulting (red) are compared with faults interpreted from 3D seismic data (blue).

9. Dawson Creek Study IITech conducts regional studies that integrates HRAM data with available surface and subsurface data sets. These studies are undertaken by a team of experienced geologists, geophysicist and remote sensing experts. The example shown here is from our regional study of the Dawson Creek area in British Columbia. The regional tectonic map shown here illustrates the results of this effort. The major faults in the study area were identified through the integration of HRAM, regional seismic and remote sensing data. The structural style and timing of the faults were interpreted through the analysis of seismic and well information. Examples of prospects and leads derived from this study are illustrated in the next slide.

10. Dawson Creek Prospects & Leads The goal of our integrated studies is to generate an inventory of leads that are well constrained with all available data sets. (a) Deflection or re-entrance of the Leduc Fringing Reef as it crosses the Clear Hills Fault Zone, with the reef being stepped progressively southwards. (b) Relationship between key Triassic clastic reservoirs and normal faulting emanating from basement structures. (c) Fault-controlled development of sandstone reservoirs on the downthrown blocks of the Dawson Creek Graben Complex, resulting from the collapse of the Peace River Arch during deposition of the Kiskatinaw formation. (d) Development of reservoir “sweetspots” along fault systems due to the effect of circulating fluids and precipitation of hydrothermal dolomite (HTD) in and around the Parkland field.

11. Rabbit Lake Structure 400m HRAM data over the Rabbit Lake structure in the NWT clearly illustrates how the location of the gas field is influenced by basement faulting. The integration of multiple data sets illustrates how the basement features propagate through the sedimentary section all the way to surface.