Results 21 to 30 of about 108 (93)

New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly

Geophysical Research Letters, 2018
The paucity of Southern Hemisphere archeomagnetic data limits the resolution of paleosecular variation models. At the same time, important changes in the modern and historical field, including the recent dipole decay, appear to originate in this region ...
Vincent J. Hare, John A. Tarduno, Thomas Huffman, Michael Watkeys, Phenyo C. Thebe, Munyaradzi Manyanga, Richard K. Bono, Rory D. Cottrell   +7 more
doaj   +1 more source

An archeomagnetic example of polyphase magnetization.

Journal of geomagnetism and geoelectricity, 1986
An unusual archeological example of multiple heating leading to superimposed thermoremanent magnetizations (TRM's) is described. The samples involved are roof-tiles which have been incorporated into the floor of a 6th century A. D. kitchen oven at a site near Potenza in southern Italy. Up to 300°C, thermal demagnetization reveals a pattern of diverging
EVANS, Michael E., MARESCHAL, Marianne
openaire   +2 more sources

Transdimensional inference of archeomagnetic intensity change [PDF]

Geophysical Journal International, 2018
One of the main goals of archeomagnetism is to document the secular changes of Earth's magnetic field by laboratory analysis of the magnetization carried by archeological artefacts. Typical techniques for creating a time-dependent model assume a prescribed temporal discretisation which, when coupled with sparse data coverage, require strong ...
Livermore, Philip, Fournier, Alexandre, Gallet, Yves, Bodin, Thomas   +3 more
openaire   +5 more sources

The time dependence of reversed archeomagnetic flux patches [PDF]

Journal of Geophysical Research: Solid Earth, 2015
AbstractArcheomagnetic field models may provide important insights to the geodynamo. Here we investigate the existence and mobility of reversed flux patches (RFPs) in an archeomagnetic field model. We introduce topological algorithms to define, identify, and track RFPs.
Terra‐nova, Filipe, Amit, Hagay, Hartmann, Gelvam, Trindade, Ricardo   +3 more
openaire   +2 more sources

Magnetic core field anomalies in the non-axial field during the last 3300 years: approach with an equivalent monopole source

Frontiers in Earth Science
The continuous update of the archeomagnetic database spanning the last 3,000 years has facilitated the refinement of geomagnetic field models, unveiling the presence of significant non-dipolar anomalies before instrumental measurements.
Pablo Rivera, Pablo Rivera, F. Javier Pavón-Carrasco, F. Javier Pavón-Carrasco, Angelo De Santis, Saioa A. Campuzano, Gianfranco Cianchini, María Luisa Osete, María Luisa Osete   +8 more
doaj   +1 more source

A Hierarchical Bayesian Model for the Global Holocene Geomagnetic Field

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 5, May 2026.
Abstract We present a hierarchical Bayesian model of the global geomagnetic field for the last 8,000 years. The model is built solely with thermoremanent records, which include archeomagnetic and volcanic data. Building upon previous work, this model includes fewer approximations and treats model hyperparameters as probabilistic variables.
M. A. Schanner, S. Panovska, M. Korte
wiley   +1 more source

Testing the Accuracy of Paleointensity Estimates Using Experimental Pottery Assemblages

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 4, April 2026.
Abstract Paleointensity estimates from archaeological pottery represent a key source of information on Holocene variations in geomagnetic field intensity. Yet, pottery rarely exhibits ideal single‐domain behavior that fully satisfies the theoretical assumptions underlying absolute paleointensity methods.
Lior Bar‐Sovik, Ron Shaar, Agnès Genevey, Yves Gallet, Yoav Vaknin, Yuval Goren   +5 more
wiley   +1 more source

Reconstruction of Core‐Surface Flows During the Last 3,300 Years

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 3, March 2026.
Abstract Understanding the Earth's magnetic field evolution requires examining the fluid flow at the core‐mantle boundary that drives the changes over different timescales. The inversion process to derive core‐surface flow velocities from secular variation data encounters non‐uniqueness issues, necessitating a priori assumptions that yield different ...
Pablo Rivera, F. J. Pavón‐Carrasco, M. L. Osete   +2 more
wiley   +1 more source

Archeointensity Database and Geomagnetic Field Reference Curves for South America Over the Past 5 Millennia

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, Filipe Terra‐Nova, Gelvam A. Hartmann, Erwan Thébault, Plinio Jaqueto, Wilbor Poletti, Ricardo I. F. Trindade   +6 more
wiley   +1 more source

Bayesian Inference of Local Paleosecular Variation From Sparse Paleomagnetic Data

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 2, February 2026.
Abstract We introduce a novel Bayesian method to construct local paleosecular variation (PSV) curves. By modeling the geomagnetic field as a Gaussian process, global models can be incorporated as informative prior distributions. Because we use Hamiltonian Monte‐Carlo methods, complex age distributions resulting for example from radiocarbon calibration ...
M. A. Schanner, R. Meyer, L. V. de Groot
wiley   +1 more source