Abstract

Magsat magnetic anomaly data for the Arctic north of 60°N latitude have been studied and field observations compared, where possible, with the extensive U.S. Navy aeromagnetic surveys by continuing the latter to the altitude level of the former. These data sets are in good qualitative agreement. The largest amplitude magnetic anomaly in this area is the high (16 nanoteslas) over the Alpha-Mendeleyev Ridge. This structure was modeled with a three-dimensional block simulation. Two 30-kilometer-thick rectangular blocks, whose dimensions were taken from the General Bathymetric Chart of the Oceans (GEBCO), were given a similar magnetization of 5 ampere/meter and used to simulate the Alpha-Mendeleyev Ridge. The model results were compared with the Magsat field, and there was agreement between observed and predicted data only for the Alpha Ridge sector. This suggests that the large amplitude of the magnetic anomaly recorded at satellite altitude over the Alpha Ridge is consistent with a continental or pseudocontinental nature for this structure.

Additional data processing of 23 east-west aeromagnetic anomaly profiles across the Beaufort Sea has been made in an effort to remove long wavelength components that result from temporal field variations. This filtering scheme has improved the definition of the lineated field in this region.