slides

MAGNETIC ANOMALIES OF PRECAMBRIAN TERRANES OF THE EAST ANTARCTIC SHIELD COASTAL REGION (20°E-50°E)

Abstract

Extensive regional magnetic survey flights with a line-spacing of about 20km were conducted by Polar Marine Geological Research Expedition (PMGRE) in 1972,1986,1988 and 1990 over the 20°E-50°E coastal region of East Antarctica. The flights total more than 34000 line-km of total magnetic intensity data acquired along north-south trending profiles. Magnetic anomaly maps compiled from digital data provide a synoptic view of major magnetic anomalies and the corresponding tectonic/geologic features of the Eastern Dronning Maud Land nd the Western Enderby Land. Availability of digital data allowed an application of various enhancement techniques and provided new interpretative information from the magnetic anomalies. The filtered and shaded relief maps have characteristic anomaly patterns (trends, amplitudes and wavelengths) which correlate with Precambrian tectonic features of the extensive Late Proterozoic area, and of the Archaean cratonic block of Enderby Land (Napier Complex). Of particular interest is the linear magnetic anomaly observed along the continental slope and shelf area; the Antarctic Continental Margin Magnetic Anomaly, ACMMA. This is a continentalscale crustal discontinuity formed during the Gondwana breakup. The archived aeromagnetic data will serve as the database for future production of the \u27Digital Magnetic Anomaly Map of Antarctica\u27 in the framework of the Scientific Committee on Antarctic Research/International Association of Geomagnetism and Aeronomy (SCAR/IAGA) compilation

    Similar works