Results 21 to 30 of about 188 (119)

Early cretaceous absolute geomagnetic paleointensities from Córdoba Province (Argentina) [PDF]

Earth, Planets and Space, 2006
Abstract We present here new paleointensity and geochronology results from Early Cretaceous volcanic rocks of Sierra Chica de Cordoba (Argentina). The new K-Ar isotopic ages of 5 samples range from 136 to 122 Ma. Twenty five samples from 7 individual flows yielded acceptable paleointensity estimates.
Rubén Cejudo, Avto Goguitchaichvili, Silvana Evangelina Geuna, L. M. Alva‐Valdivia, Jesús Solé, Juan Morales   +5 more
openaire   +4 more sources

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

Evidence for Missing Geomagnetic Reversals From Geomagnetic Reversal Frequency Model Using Adaptive Kernel Density Estimation

Geophysical Research Letters, Volume 53, Issue 4, 28 February 2026.
Abstract The existence of missing geomagnetic reversals has been proposed, with potential for new magnetostratigraphic age controls. We estimate geomagnetic reversal frequency from 0 to 155 Ma using adaptive‐bandwidth kernel density estimation (AKDE) to evaluate data sparseness and to assess how reversal frequency changes when recently identified ...
Yutaka Yoshimura, Masakazu Fujii, Hideitsu Hino, Shotaro Akaho, Satoshi Kuriki, Osamu Ishizuka, Toshitsugu Yamazaki, Hyeon‐Seon Ahn, Tesfaye Kidane, Yuhji Yamamoto, Yo‐ichiro Otofuji   +10 more
wiley   +1 more source

Paleointensity Determination Using the Thellier Technique

Journal of geomagnetism and geoelectricity, 1986
The Thellier technique is discussed, specifically in respect of small (3×3mm) samples measured using a cryogenic magnetometer. It is concluded that as long as stringent criteria are imposed the technique gives reliable results. Agreement with the Shaw technique is noted, as also with observatory-based values.
M. J. AITKEN, A. L. ALLSOP, G. D. BUSSELL, M. WINTER   +3 more
openaire   +2 more sources

Reconstructing Late Pleistocene to Prehistorical Holocene Geomagnetic Field Variations From La Palma Lava Flows (Canary Islands, Spain): Unraveling Viscous Components

Journal of Geophysical Research: Solid Earth, Volume 131, Issue 2, February 2026.
Abstract We present new vector paleomagnetic data from 13 radiometrically dated lava‐flows in southern La Palma (Canary Islands) spanning from 1 to 56 ka, which covers most of the Late Pleistocene to prehistoric Holocene volcanic record in the island.
Eva Vernet, Manuel Calvo‐Rathert, Ángel Carrancho, Yuhji Yamamoto, Lidia Rodríguez‐Méndez, Josep M. Parés, Vicente Soler   +6 more
wiley   +1 more source

Characteristics of Natural Remanence Records in Fine‐Grained Particles Returned From Asteroid Ryugu

Journal of Geophysical Research: Planets, Volume 131, Issue 2, February 2026.
Abstract Particles collected from the asteroid Ryugu by the Hayabusa2 spacecraft offer a unique opportunity to investigate the magnetic record of the primitive solar system, as any terrestrial magnetic contamination is minimal and can be accounted for.
Masahiko Sato, Yuki Kimura, Tadahiro Hatakeyama, Tomoki Nakamura, Satoshi Okuzumi, Sei‐ichiro Watanabe, Seiji Sugita, Satoshi Tanaka, Shogo Tachibana, Hisayoshi Yurimoto, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Hiroshi Naraoka, Kanako Sakamoto, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Fuyuto Terui, Satoru Nakazawa, Yuichi Tsuda   +27 more
wiley   +1 more source

Decadal‐Scale In Situ Scanning of a Stalagmite From Southwest China Reveals Blake Geomagnetic Excursion Structure

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract We present a decadal‐scale paleomagnetic analysis of a stalagmite collected from Shuixi Cave, southwest China, spanning 89−123 ka. Our findings include: (a) Magnetite is the dominant magnetic mineral, and paleomagnetic directions can be obtained via demagnetization; (b) Magnetic scanning at 0.1‐mm resolution captures key magnetic features ...
Zhongshan Shen, Youwei Li, Liang Yi, Huafeng Qin, Jian Wang, Yibing Li, Hai Cheng   +6 more
wiley   +1 more source

Effects of Aging on Magnetic Mineralogy of Natural Volcanic Glass: Implications for Geomagnetic Paleointensity Recorders

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 1, January 2026.
Abstract Natural volcanic glasses are well represented in the geologic record, and typically contain near‐ideal single‐domain particles required for standard Thellier‐type absolute paleointensity experiments. Young (<∼50–100 ka) glasses have been demonstrated to reliably record Earth's magnetic field.
Julie A. Bowles, Fatimah Abdulghafur, Sebastian Fearn, Vera Soltes   +3 more
wiley   +1 more source

A geomagnetic estimate of mean paleointensity [PDF]

Journal of Geophysical Research: Solid Earth, 2006
A statistical hypothesis about Earth's magnetic field is tested against paleomagnetism by combining it with the present field to estimate mean paleointensity. The estimate uses the satellite era geomagnetic multipole power spectrum Rn, which gives the mean square magnetic induction represented by spherical harmonics of degree n averaged over the sphere
openaire   +1 more source

Brunhes Paleomagnetic Directions and Paleointensities From Northern Hainan Island

Geochemistry, Geophysics, Geosystems, Volume 27, Issue 1, January 2026.
Abstract Paleomagnetic studies typically assume that the long‐term, time‐averaged geomagnetic field behaves as a geocentric axial dipole (GAD). While paleodirectional data over the past five million years generally agree with GAD predictions, mid‐to‐low latitude paleointensity records fail to show GAD, with high values from Hawaii.
Mengqing Wang, Huapei Wang, Huafeng Qin, Jian Luo, Chen Wen, Fei Han, Yiming Ma, Jiabo Liu   +7 more
wiley   +1 more source