Premium
Seven thousand year duration for a geomagnetic excursion constrained by 230 Th xs
Author(s) -
Knudsen Mads Faurschou,
Henderson Gideon M.,
Mac Niocaill Conall,
West A. Joshua
Publication year - 2007
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2007gl031090
Subject(s) - excursion , geology , earth's magnetic field , geomagnetic reversal , paleomagnetism , duration (music) , polarity (international relations) , magnetostratigraphy , dynamo theory , seafloor spreading , secular variation , polarity reversal , geophysics , greigite , dynamo , flux (metallurgy) , paleontology , physics , magnetic field , magnetite , genetics , materials science , quantum mechanics , voltage , biology , political science , acoustics , law , metallurgy , cell
The duration of geomagnetic excursions may provide important information about the geodynamo. It has proven difficult, however, to assess the exact duration of both excursions and reversals. We combine high‐resolution paleomagnetic records from marine sediments with measurements of the 230 Th xs flux to the seafloor in order to better constrain the duration of the Iceland Basin Excursion (IBE). We find the duration of the IBE to be ∼7–8 kyr, implying that it is considerably longer than previous estimates for the Laschamp Excursion (∼2 kyr), and more similar in duration to that of full polarity reversals. There may not be, therefore, a characteristic timescale for transitional field configurations that distinguishes excursions from reversals.