10Be and 9Be in South Atlantic DSDP Site 519: Relation to geomagnetic reversals and to sediment composition

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24

Scientific paper

A high-resolution 10Be profile has been measured on DSDP Site 519 (central South Atlantic) in order to search for changes in the flux of 10Be into a pelagic sediment during geomagnetic reversals as compared with times of constant magnetic polarity. The decay corrected 10Be concentrations range from 1 to 9 × 108 at/g. The average 10Be flux rate is 5 × 108 [at cm-2 kyr-1]. 9Be and CaCO3 were measured on the same samples. The 10Be vs. depth curve is overall similar to the 9Be vs. depth curve, while the CaCO3 vs. depth curve anticorrelates the beryllium isotope curves closely, implying that Be is carried mainly by the non-CaCO3 phases of the sediment. The positive correlation between 10Be and 9Be along with the fact that the average 10Be/9Be ratio of 5.5 × 10-8 is within the range of 10Be/9Be ratios reported for deep ocean water leads us to conclude (1) that the beryllium isotopes come close to an equilibrium in the open ocean, and (2) that the 10Be/9Be in deep sea sediments with a low detrital component monitors the 10Be/9Be of deep ocean water through time. Relative increases of the 10Be/9Be ratio are observed in the vicinity of the geomagnetic reversals, but the relationship between reversals and higher 10Be/9Be remains doubtful. Other mechanisms which could alter the 10Be/9Be ratio are discussed (input of 10Be by melting of glacial ice; changing input of 9Be due to changes in continental erosion; changing deep ocean circulation; changing scavenging activity at ocean margins), but as yet no conclusive explanation for the observed behavior of the beryllium isotopes can be given.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

10Be and 9Be in South Atlantic DSDP Site 519: Relation to geomagnetic reversals and to sediment composition 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 10Be and 9Be in South Atlantic DSDP Site 519: Relation to geomagnetic reversals and to sediment composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and 10Be and 9Be in South Atlantic DSDP Site 519: Relation to geomagnetic reversals and to sediment composition will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-985256

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.