Journal ArticleDOI
Magnetic Anomalies over Oceanic Ridges
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TLDR
Vine and Matthews as mentioned in this paper showed that the pattern of local magnetic anomalies on the flanks of a mid-oceanic ridge is strongly lineated parallel to the ridge, and that these magnetic "stripes" represent strips of material in the upper mantle the directions of permanent magnetization of which are alternately parallel and anti-parallel to the present local geomagnetic field.Abstract:
Vine and Matthews1 suggest that the pattern of local magnetic anomalies on the flanks of a mid-oceanic ridge is strongly lineated parallel to the ridge, and that these magnetic ‘stripes’ represent strips of material in the upper mantle the directions of permanent magnetization of which are alternately parallel and anti-parallel to the present local geomagnetic field. Vine and Matthews suggest that mantle material cools as it rises convectively under a ridge and then spreads2 horizontally outward. As the material cools through its Curie point it is magnetized parallel to the contemporary local geomagnetic field. Because this field reverses quasi-periodically3,4 with a period 2T, T being of the order of 0.5–1.0 million years, stripes of alternate permanent magnetization are produced the width of which is vT, v being the local horizontal velocity with which material at the surface of the mantle spreads away from the centre of the ridge. The stripes are observed1 to have widths of the order of 20 km. If T is 0.5 million years, v is 4 cm/yr. Convective velocities of this order are also indicated by palaeomagnetic data5.read more
Citations
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A new geomagnetic polarity time scale for the Late Cretaceous and Cenozoic
Steven C. Cande,Dennis V. Kent +1 more
TL;DR: In this article, the relative widths of the magnetic polarity intervals for the entire Late Cretaceous and Cenozoic have been systematically determined from magnetic profiles from the world's ocean basins.
Journal ArticleDOI
Spreading of the ocean floor: new evidence
TL;DR: The hypothesis that magnetic anomalies may indicate the nature of oceanic fracture zones and distinguish the parts of the ridge system that are actively spreading is suggested and data derived during the past year lend remarkable support to the hypothesis.
Book
Fundamentals of Geophysics
TL;DR: The most popular undergraduate textbook for geophysics is the Geophysics: A Coursebook for Undergraduates as mentioned in this paper, which contains twelve chapters covering the same breadth of topics as earlier editions, but in a substantially modernized fashion to facilitate classroom teaching.
Journal ArticleDOI
EMAG2: A 2-arc min resolution Earth Magnetic Anomaly Grid compiled from satellite, airborne, and marine magnetic measurements
Stefan Maus,Stefan Maus,Udo Barckhausen,H. A. Berkenbosch,N. Bournas,John Brozena,Vicki A. Childers,F. Dostaler,J. D. Fairhead,Carol A. Finn,R. R. B. von Frese,Carmen Gaina,S. Golynsky,Robert P. Kucks,Hermann Lühr,Peter Milligan,Saad Mogren,Ralph Müller,Odleiv Olesen,Mark Pilkington,Richard W. Saltus,Bernd Schreckenberger,Erwan Thébault,F. Caratori Tontini +23 more
TL;DR: In this article, a global Earth Magnetic Anomaly Grid (EMAG2) has been compiled from satellite, ship, and airborne magnetic measurements, both over land and the oceans, where the original shipborne and airborne data were used instead of precompiled oceanic magnetic grids.
Journal ArticleDOI
A Paleolatitude Calculator for Paleoclimate Studies
Douwe J.J. van Hinsbergen,Lennart V. de Groot,Sebastiaan J. van Schaik,Wim Spakman,Peter K. Bijl,Appy Sluijs,Cor G. Langereis,Henk Brinkhuis +7 more
TL;DR: It is shown that using a mantle reference frame, which defines plate positions relative to the mantle, instead of a paleomagnetic reference frame may introduce errors in paleolatitude of more than 15° (>1500 km), because mantle reference frames cannot constrain, or are specifically corrected for the effects of true polar wander.
References
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Journal ArticleDOI
Geomagnetic Polarity Epochs and Pleistocene Geochronometry
Journal ArticleDOI
Horizontal displacements in the floor of the northeastern pacific ocean
TL;DR: A total magnetic intensity survey in the northeastern Pacific Ocean revealed a north-south pattern of magnetic anomalies, which is cut through by the Murray, the Pioneer, and the Mendocino faults as discussed by the authors.
Journal ArticleDOI
Magnetic correlation in volcanic districts
TL;DR: In this paper, the authors investigated Tertiary and Quaternary plateau basalts in Iceland and found that both normal and reverse natural permanent magnetization is present in alternating zones of about 25 flows each.
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