Results 141 to 150 of about 346 (179)

Introduction to Paleointensity Articles

Reviews of Geophysics, 1988
After indicating the basis of the technique, its use with a cryogenic SQUID magnetometer is outlined, particular emphasis being given to the need for stringent reliability criteria. Comparison of results for some samples is made with results obtained using the Shaw alternating‐field technique, and the agreement is satisfactory.
Ronald T. Merrill, J. R. Heirtzler
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Paleointensity determinations of lunar samples

Physics of the Earth and Planetary Interiors, 1977
Abstract Evidence for the existence of an ancient lunar field comes from the NRM of lunar rocks and from measurements of local lunar surface magnetic fields. Even when the Fe particles present in the rocks possess enough magnetic stability to preserve a record of the original magnetizing field, there are considerable difficulties in estimating the ...
D.W. Collinson, A. Stephenson
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Paleointensity Bursts in the Geomagnetic Field History

Geomagnetism and Aeronomy, 2020
Regularities in the distribution of extreme (burst) increases in paleointensities from 3000 Ma to the present have been studied. Paleointensity bursts that exceed several times its average values Havg have been found to occur over the entire geomagnetic history.
A. Yu. Kurazhkovskii, N. A. Kurazhkovskaya, B. I. Klain   +2 more
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Meteorite magnetization and paleointensity

Advances in Space Research, 1982
Abstract The five chemical classes of chondrite, i.e. E-, H-, L-, LL- and C-chondrite, and three major classes of achondrite, i.e. diogenite, eucrite plus howardite, and ureilite, are magnetically identified to respective separated domains on an Is (α)/Is versus Is diagram, where Is and Is (α) denote respectively the saturation magnetization and the ...
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Absolute paleointensity and magnetomineralogical changes

Journal of Geophysical Research: Solid Earth, 1996
Determinations of absolute paleointensity are often hampered by magnetomineralogical changes produced within samples of lava flows during successive heatings. Such changes which directly affect the capacity for a sample to acquire a partial thermoremanent magnetization (PTRM) are reflected by negative pTRM checks, a deviation between the original pTRM ...
Valet, Jean-Pierre, Brassart, Jacques, Le Meur, Isabelle, Soler, Vicente, Quidelleur, Xavier, Tric, Emmanuel, Gillot, Pierre-Yves   +6 more
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Latest Pleistocene and Holocene Geomagnetic Paleointensity on Hawaii

Science, 1993
Geomagnetic paleointensity determinations from radiocarbon-dated lava flows on the island of Hawaii provide an estimate of broad trends in paleointensity for Holocene time and offer a glimpse of intensity variations near the end of the last glacial period.
E A, Mankinen, D E, Champion
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Sawtooth paleointensity and reversals of the geomagnetic field

Physics of the Earth and Planetary Interiors, 1997
Abstract Valet and Meynadier (Valet, J.P., Meynadier, L., 1993) noted an intriguing sawtooth intensity pattern in sequences drilled during Leg 138 of the Ocean Drilling Program. The pattern is an almost linear decrease in intensity during stable polarity times followed by a rapid recovery or increase in intensity immediately after a reversal.
P.L. McFadden, R.T. Merrill
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Multivectorial paleointensity determination by the Thellier method

Journal of Geophysical Research: Solid Earth, 2006
Theoretical and experimental study of shape of the Arai‐Nagata diagrams for the natural remanent magnetization (NRM) consisting of two low‐ and high‐temperature partial thermal remanent magnetization vectors directed at angle θ to each other is considered.
V. P. Shcherbakov, G. V. Zhidkov
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A review of lunar paleointensity data

Advances in Space Research, 1982
Abstract An extension of the saturation remanence normalization method to over 50 samples implies that a lunar surface field, comparable in intensity to the Earth's magnetic field, existed from about 3.65 to 3.85 AE. Absolute paleointensity estimates published to date, and surface field strengths, as measured by the Apollo subsatellites, are in ...
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Paleointensity determination by a modified thellier method

Physics of the Earth and Planetary Interiors, 1977
Abstract It has been frequently observed that the ferromagnetic minerals in volcanic rocks may undergo some physical/chemical changes when they are heated in a laboratory. For paleointensity determinations, it is therefore desirable to use the Thellier method, in which internal consistency of the data assures that such undesirable changes did not ...
Masaru Kono, Naoko Ueno
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