Back to Search
Start Over
Direct radiometric dating of the Devonian-Mississippian time-scale boundary using the Re-Os black shale geochronometer.
- Source :
-
Geology . Jul2005, Vol. 33 Issue 7, p545-548. 4p. - Publication Year :
- 2005
-
Abstract
- Many Phanerozoic time-scale boundaries are characterized by oceanic anoxia and mass extinction events with the deposition of black shale. The Re-Os isotope system in black shale can be used to provide depositional ages for these rocks, thus yielding direct radiometric ages for time-scale boundaries. We demonstrate that the Re-Os black shale geochronometer can yield precise ages useful for time-scale research through study of the Devonian-Mississippian boundary within the Exshaw Formation, Canada. The Re-Os date determined places the Devonian-Mississippian boundary at 361.3 ± 2.4 Ma (2σ including λ uncertainty, model 1, mean square of weighted deviates = 1.2), in accord with recent calibration interpolated from U-Pb zircon dates (360.7 ± 0.7 Ma) for the Hasselbachtal section, Germany. [ABSTRACT FROM AUTHOR]
- Subjects :
- *RADIOACTIVE dating
*HYPOXEMIA
*ISOTOPES
*ZIRCON
Subjects
Details
- Language :
- English
- ISSN :
- 00917613
- Volume :
- 33
- Issue :
- 7
- Database :
- Academic Search Index
- Journal :
- Geology
- Publication Type :
- Academic Journal
- Accession number :
- 17540915
- Full Text :
- https://doi.org/10.1130/G21324.1