New Production Rate Estimates for In Situ Cosmogenic 14 C Cronus-Earth/EU Workshop, Vancouver, July...

Post on 16-Dec-2015

212 views 0 download

Transcript of New Production Rate Estimates for In Situ Cosmogenic 14 C Cronus-Earth/EU Workshop, Vancouver, July...

New Production Rate Estimates for New Production Rate Estimates for In Situ Cosmogenic In Situ Cosmogenic 1414CC

Cronus-Earth/EU Workshop, Vancouver, July 12-13 2008Cronus-Earth/EU Workshop, Vancouver, July 12-13 2008

Bailey Dugan, Nathaniel Lifton, A.J. Timothy JullBailey Dugan, Nathaniel Lifton, A.J. Timothy JullUniversity of ArizonaUniversity of Arizona

Funded By The U.S. National Science FoundationFunded By The U.S. National Science Foundation

Promontory Point ResultsPromontory Point Results

Site Production Rates Site Production Rates Generally Consistent Generally Consistent w/Earlier Estimatesw/Earlier Estimates ReplicatesReplicates

Unexplained VariabilityUnexplained Variability Use Weighted MeansUse Weighted Means

05PPT-0205PPT-02 Replicates AgreeReplicates Agree >2>2 Below Site Weighted Below Site Weighted

MeanMean No Obvious ReasonNo Obvious Reason Higher Position on Higher Position on

05PPT-01 Outcrop05PPT-01 Outcrop Excluded from Further Excluded from Further

AnalysisAnalysis

Additional Analyses Additional Analyses PlannedPlanned

CRONUS-Earth

49.7 ± 1.3 w/05PPT-0249.7 ± 1.3 w/05PPT-0251.4 ± 0.8 w/o 05PPT-0251.4 ± 0.8 w/o 05PPT-02

49.7 ± 1.3 w/05PPT-0249.7 ± 1.3 w/05PPT-0251.4 ± 0.8 w/o 05PPT-0251.4 ± 0.8 w/o 05PPT-02

Corrie Nan Arr ResultsCorrie Nan Arr Results

Good Agreement Good Agreement Between Supra- and Between Supra- and Sub-Glacial BouldersSub-Glacial Boulders Supports Assumption of Supports Assumption of

Landslide Deposition on Landslide Deposition on Retreating GlacierRetreating Glacier

Additional Analyses Additional Analyses PlannedPlanned

CRONUS-Earth

Maol Chean-Dearg Maol Chean-Dearg (Mull Kin Jerig)(Mull Kin Jerig) ResultsResults

Site Production Rates Site Production Rates Show Generally Good Show Generally Good AgreementAgreement ReplicatesReplicates

Unexplained VariabilityUnexplained Variability Use Weighted MeansUse Weighted Means

Additional Analyses Additional Analyses PlannedPlanned

CRONUS-Earth

Sea Level, High Latitude Sea Level, High Latitude (SLHL)(SLHL) ProductionProduction

CRONUS-Earth

Four Scaling Models ComparedFour Scaling Models Compared Lal (1991)/Stone(2000)Lal (1991)/Stone(2000) Dunai (2001)Dunai (2001) Desilets & Zreda (2003)/Desilets et al. (2006)Desilets & Zreda (2003)/Desilets et al. (2006) Lifton et al. (2005)Lifton et al. (2005)

Variable Atmosphere Assumed for AllVariable Atmosphere Assumed for All Geomagnetic AssumptionsGeomagnetic Assumptions

Geocentric Axial Dipole for Lal/StoneGeocentric Axial Dipole for Lal/Stone Continuous Geomagnetic Model of Lifton et al. (2008) for OthersContinuous Geomagnetic Model of Lifton et al. (2008) for Others

Scale to SLHLScale to SLHL