Technical Papers - Airborne Magnetics

Exploration Applications of Three Dimensional Gradient Magnetics in the Western Canada Sedimentary Basin and the Fold Best Region

By Dr. Zeev Berger , Jim Davies and Robin T. Thompson, Image Interpretation Technologies Inc.
Terence J. McConnell, Bob Lo and Alastair Ryder-Turner, Fugro Airborne Surveys
Dr. Paul MacKay, Northstar Energy Corporation

Abstract

Airborne magnetic mapping has been used in petroleum exploration for decades, with the last five years having seen a renaissance in the use of the magnetic techniques. In addition to the detection of basement structures, newer High Resolution Aeromagnetic (HRAM) surveys have focused on measuring weakly magnetic faults and lithologies of the sedimentary section, near surface paleo-channels, and the size and shape of salt intrusions.

In the WCSB and the Foothills regions, modern HRAM surveys have been widely used for regional mapping of deep seated faults and fracture systems that control the development of reservoirs in the carbonate section (Berger 1998; Peirce et al. 1998; Berger and Davies 1999). These HRAM surveys are usually flown on a fixed wing platform with a 100 metre mean terrain clearance (drape) and line spacing of 800-400 metres. Unfortunately, they do not always provide sufficient information for detailed structural mapping at the prospect level. Also, the utility of this technology is limited in Foothills exploration because fixed wing aircraft cannot maneouver over rugged mountain terrain while maintaining a constant (drape) elevation of 100 metres.

Recently developed, helicopter-borne three dimensional gradient magnetics technology has been used to collect data with 50 metre line spacing over several key producing fields in the WCSB and the Foothills. The objective of this paper is to describe the technology and illustrate its exploration application for prospect mapping in these areas.

Reservoir, September 1999

Download Technical Paper (PDF 279 Kb)