Results 81 to 90 of about 4,304 (252)
Absolute Thellier paleointensities from Ponta Grossa dikes (southern Brazil) and the early Cretaceous geomagnetic field strength [PDF]
Geofísica Internacional, 2009 We report a detailed rock magnetic and Thellier paleointensity study from ~ 130.5 Ma Ponta Grossa Dike Swarms in Southern Brazil. Twenty-nine samples from seven cooling units were pre-selected for paleointensity experiments based on their low viscosity ...
J. Urrutia-Fucugauchi +5 more
doaj
Geochemistry, Geophysics, Geosystems, 2014 Information on the strength of the geomagnetic field is important for understanding the behavior of the geodynamo. Polarity reversal frequency increases toward the late Cenozoic since the end of the Cretaceous Normal Superchron.
Toshitsugu Yamazaki, Yuhji Yamamoto
doaj +1 more source
A New View of Long-Term Geomagnetic Field Secular Variation
Frontiers in Earth Science, 2018 This study carries out a statistical analysis of high-resolution PSV records for the last ~70 ka from three different regions of the Earth. We consider directional and intensity variability in each region on time scales of 103-105 years in order to ...
Steve P. Lund
doaj +1 more source
Geochemistry, Geophysics, Geosystems, Volume 27, Issue 3, March 2026.Abstract Marine sediments contain magnetic mineral particles of detrital, biogenic and authigenic origin that record changes in the direction and intensity of the geomagnetic field over geological time. Previous studies have demonstrated that the recording efficiencies of detrital and biogenic magnetite differ.
Kuang He +8 more
wiley +1 more source
Variability of Millennial-Scale Trends in the Geomagnetic Axial Dipole [PDF]
, 2019 The historical trend in the axial dipole is sufficient to reverse the field in less than 2 kyr. Assessing the prospect of an imminent polarity reversal depends on the probability of sustaining the historical trend for long enough to produce a reversal ...
Avery, MS, Buffett, B, Davis, W
core +1 more source
Journal of Geophysical Research: Solid Earth, Volume 131, Issue 3, March 2026.Abstract The study of variations in geomagnetic field intensity over time and space is crucial to understand the evolution of the geodynamo and its interactions with the Earth's surface. In this work, we introduce the SAGEOMAG (South America GEOMAGnetic) database, a comprehensive and updated repository of geomagnetic field intensity records derived ...
Victor J. O. Marum +6 more
wiley +1 more source
Magnetism of a very young lunar glass [PDF]
, 2015 Recent paleomagnetic studies of Apollo samples have established that a core dynamo existed on the Moon from at least 4.2 to 3.56 billion years (Ga). Because there is no lunar dynamo today, a longstanding mystery has been the origin of magnetization in ...
Buz, Jennifer +5 more
core +1 more source
Journal of Geophysical Research: Solid Earth, Volume 131, Issue 3, March 2026.Abstract Micropaleomagnetic analysis offers a path to high‐precision reconstructions of ancient magnetic fields from terrestrial and space‐returned samples by inverting the vertical stray field of individual particles to recover their magnetic moments through the use of magnetic microscopes.
U. D. Bellon +9 more
wiley +1 more source
Paleomagnetic studies on single crystals separated from the middle Cretaceous Iritono granite
Earth, Planets and Space, 2018 Investigations of superchrons are the key to understanding long-term changes of the geodynamo and the mantle’s controlling role. Granitic rocks could be good recorders of deep-time geomagnetic field behavior, but paleomagnetic measurements on whole-rock ...
Chie Kato +4 more
doaj +1 more source
GEOMAGIA50.v3: 1. general structure and modifications to the archeological and volcanic database [PDF]
, 2015 Background: GEOMAGIA50.v3 is a comprehensive online database providing access to published paleomagnetic, rock magnetic, and chronological data from a variety of materials that record Earth’s magnetic field over the past 50 ka.Findings: Since its ...
Brown, Maxwell C +7 more
core +1 more source