Identification of the short-lived Santa Rosa geomagnetic excursion in lavas on Floreana Island (Galapagos) by40Ar/39Ar geochronology

Geology ◽  
2016 ◽  
Vol 44 (5) ◽  
pp. 359-362 ◽  
Author(s):  
Andrea Balbas ◽  
Anthony A.P. Koppers ◽  
Dennis V. Kent ◽  
Kevin Konrad ◽  
Peter U. Clark
1990 ◽  
Vol 96 (3-4) ◽  
pp. 443-457 ◽  
Author(s):  
Shaul Levi ◽  
Haraldur Audunsson ◽  
Robert A. Duncan ◽  
Leo Kristjansson ◽  
Pierre-Y. Gillot ◽  
...  

1980 ◽  
Vol 7 (5) ◽  
pp. 337-340 ◽  
Author(s):  
Leo Kristjansson ◽  
Agust Gudmundsson

1979 ◽  
Vol 84 (B1) ◽  
pp. 261-271 ◽  
Author(s):  
Joseph C. Liddicoat ◽  
Robert S. Coe

1973 ◽  
Vol 244 (131) ◽  
pp. 8-10 ◽  
Author(s):  
T. NAKAJIMA ◽  
K. YASKAWA ◽  
N. NATSUHARA ◽  
N. KAWAI ◽  
S. HORIE

2018 ◽  
Vol 115 (36) ◽  
pp. 8913-8918 ◽  
Author(s):  
Yu-Min Chou ◽  
Xiuyang Jiang ◽  
Qingsong Liu ◽  
Hsun-Ming Hu ◽  
Chung-Che Wu ◽  
...  

Polarity reversals of the geomagnetic field have occurred through billions of years of Earth history and were first revealed in the early 20th century. Almost a century later, details of transitional field behavior during geomagnetic reversals and excursions remain poorly known. Here, we present a multidecadally resolved geomagnetic excursion record from a radioisotopically dated Chinese stalagmite at 107–91 thousand years before present with age precision of several decades. The duration of geomagnetic directional oscillations ranged from several centuries at 106–103 thousand years before present to millennia at 98–92 thousand years before present, with one abrupt reversal transition occurring in one to two centuries when the field was weakest. These features indicate prolonged geodynamo instability. Repeated asymmetrical interhemispheric polarity drifts associated with weak dipole fields likely originated in Earth’s deep interior. If such rapid polarity changes occurred in future, they could severely affect satellites and human society.


1996 ◽  
Vol 23 (17) ◽  
pp. 2271-2274 ◽  
Author(s):  
D. W. Peate ◽  
J. H. Chen ◽  
G. J. Wasserburg ◽  
D. A. Papanastassiou ◽  
J. W. Geissman

2004 ◽  
Vol 227 (3-4) ◽  
pp. 331-343 ◽  
Author(s):  
Hervé Guillou ◽  
Brad S. Singer ◽  
Carlo Laj ◽  
Catherine Kissel ◽  
Stéphane Scaillet ◽  
...  

Radiocarbon ◽  
2010 ◽  
Vol 52 (1) ◽  
pp. 129-147 ◽  
Author(s):  
Weijian Zhou ◽  
Feng Xian ◽  
J Warren Beck ◽  
A J Timothy Jull ◽  
Zhisheng An ◽  
...  

Efforts to extract weak geomagnetic excursion signals from Chinese loess-paleosol 10Be have generally been unsuccessful due to the complexities of its accumulation, because the geomagnetic and climate (precipitation and dust) signals contained in loess-paleosol sequence are tightly overprinted. Here, we present a reconstruction of geomagnetic relative paleointensities for the past 130 kyr from 10Be records in 2 Chinese loess-paleosol sections using a correction based on the correlation of 10Be with magnetic susceptibility (SUS) to remove the climatic contamination. Both these records reveal the Laschamp and Blake events, which lie in the loess and paleosol (L1SS1 and S1SS3) horizons corresponding to mid-MIS 3 and 5e, respectively. The good agreement between our results and other geomagnetic intensities reconstructions from Atlantic and Pacific sediments indicates that our method is robust. Our study suggests the potential application of loess-paleosol 10Be for reconstructing geomagnetic intensity variations spanning the whole Quaternary.


1977 ◽  
Vol 14 (9) ◽  
pp. 2007-2012 ◽  
Author(s):  
G. Vilks ◽  
J. M. Hall ◽  
David J. W. Piper

Two sediment cores collected from the continental slope of the southeastern Beaufort Sea show zones of stable shallow geomagnetic inclination at close to 0° in contrast with the dipole value of 80°. Although the cores were taken 60 km apart, the shallow inclination sections are sufficiently similar in form to be useful as potential correlation horizons, on the reasonable assumption that the same geomagnetic excursion is recorded in both cores.The cores consist of silt and clay, showing fine silt–clay laminae or structureless mud on X-radiographs. Except for the surface 2.5 m of core 810, foraminifera are sparse everywhere.The 14C dates for total organic carbon place the recorded paleomagnetic event at between 10 000 and 40 000 years BP. According to paleontologic evidence, the event took place between 6 000 and 16 000 years BP. The later dating method is considered to be more reliable. Sediment cores from other high deposition rate areas need to be examined paleomagnetically to determine the areal extent of this Beaufort Sea geomagnetic excursion.


Sign in / Sign up

Export Citation Format

Share Document