Results 181 to 190 of about 2,212 (217)

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 across the Réunion event in Ethiopia

Earth and Planetary Science Letters, 1999
Abstract Paleointensity experiments have been conducted on a volcanic series of 33 flows which recorded the geomagnetic Reunion event. Successive determinations of absolute paleointensity from 20 flows indicate that the Reunion event would actually be characterized by two successive periods of low field intensity, with a total duration not in excess ...
Julie Carlut, Jean-Pierre Valet, Xavier Quidelleur, Vincent Courtillot, Tesfaye Kidane, Yves Gallet, Pierre-Yves Gillot   +6 more
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The inverse problem of paleointensity determination

Physics of the Earth and Planetary Interiors, 2004
Abstract Analysis of paleointensity experimental data is often carried out using a special simple case of error-in-variable (EIV) formalism. Though mathematically sound, this approach is quite limited in the ways it offers to assess uncertainty and quality of the paleointensity estimates.
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