Physics – Geophysics
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010ggg....110aa12c&link_type=abstract
Geochemistry Geophysics Geosystems, Volume 11, CiteID Q0AA12
Physics
Geophysics
10
Geomagnetism And Paleomagnetism: Reversals: Process, Timescale, Magnetostratigraphy, Geochronology: Radioisotope Geochronology, Paleoceanography: Astronomical Forcing
Scientific paper
When five Matuyama-Brunhes (M-B) boundary records from the North Atlantic are placed on isotope age models, produced by correlation of the δ18O record directly or indirectly to an ice volume model, the M-B boundary lies consistently at the young end of marine isotope stage 19 with a mean age for the midpoint of the reversal of 773.1 ka (standard deviation = 0.4 kyr), ˜7 kyr younger than the presently accepted astrochronological age for this polarity reversal (780-781 ka). Two recently proposed revisions of the age of the 40Ar/39Ar Fish Canyon sanidine (FCs) standard to 28.201 ± 0.046 Ma and 28.305 ± 0.036 Ma would adjust 40Ar/39Ar ages applicable to the M-B boundary (and other reversals and excursions back to 1.2 Ma) to ages older than the new astrochronological ages by 8-24 kyr. The variables used to construct the ice volume models cannot account for the discrepancy. The FCs standard age that best fits the astrochronological ages is 27.93 Ma, which is within the uncertainty associated with the commonly used value of 28.02 (±0.16) Ma but younger than the recently proposed FCs ages. The EDC2 and EDC3 age models in the Dome C (Antarctic) ice core yield ages of 771.7 ka and 766.4 ka, respectively, for the 10Be flux peak that denotes the paleointensity minimum at the reversal boundary, implying that the EDC2 (rather than EDC3) age model is consistent with the observations from marine sediments, at least close to the M-B boundary.
Channell James E. T.
Hodell David A.
Singer Brad S.
Xuan Chuang
No associations
LandOfFree
Reconciling astrochronological and 40Ar/39Ar ages for the Matuyama-Brunhes boundary and late Matuyama Chron does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Reconciling astrochronological and 40Ar/39Ar ages for the Matuyama-Brunhes boundary and late Matuyama Chron, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reconciling astrochronological and 40Ar/39Ar ages for the Matuyama-Brunhes boundary and late Matuyama Chron will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1292957