Magnetic Pattern of the Western Atlantic South of 40 N

• Main Authors: Einwich,Anna M, Vogt,Peter R
• Other Authors: NAVAL OCEAN RESEARCH AND DEVELOPMENT ACTIVITY NSTL STATION MS
• Format: Text
• Language: English
• Published: 1978
• Subjects: Physical and Dynamic Oceanography; Geology; Geochemistry and Mineralogy; *MAGNETIC FIELDS; *MARINE GEOLOGY; *SEAFLOOR SPREADING; COASTAL REGIONS; PATTERNS; OCEAN BOTTOM SAMPLING; NORTH ATLANTIC OCEAN; SEDIMENTS; NORTH AMERICA; MAGNETIC ANOMALIES; North Atlantic
• Online Access: http://www.dtic.mil/docs/citations/ADA079833; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA079833

The magnetic pattern in the western North Atlantic near the east coast of North America is dominated by a linear region of low magnetic intensities. This magnetic 'quiet zone' possesses characteristics of seafloor spreading: linearity, continuity, and bilateral symmetry with the quiet zone found in the easternn Atlantic. Its small internal anomalies can be shown to have a spatial origin. Some appear linear, but discontinuous, and a degree of correlation can be found over large, intervening distances. A portion of the quiet zone shows possible subdivision into an inner and outer smooth zone. The inner smooth zone, near the shelf edge, has no counterpart in the eastern Atlantic, and, when considered as the development of a proto-Atlantic, could account for the comparatively greater width of the total western quiet zone. Pre-rift fits of the African and North American continents usually show the African continental margin superimposed on both the inner smooth zone and the unique anomalies of the Blake Plateau which lies to the south. An oceanic origin for the inner smooth zone implies the same origin for a major part of the Blake Plateau. The magnetic zones show little relationship with present current-shaped seafloor topography, but offsets in the lineations of prominent anomalies attest to displacements in the rock floor beneath the sediments.