Articles | Volume 3, issue 2
https://doi.org/10.5194/gchron-3-395-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gchron-3-395-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Jul 2021
Research article |
| 15 Jul 2021
| 15 Jul 2021
Exposure dating of detrital magnetite using 3He enabled by microCT and calibration of the cosmogenic 3He production rate in magnetite
Division of Geological and Planetary Sciences, California Institute of Technology, MC 100-23, 1200 E California Blvd, Pasadena, CA 91125,
USA
Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333 Munich, Germany
Emily H. G. Cooperdock
Department of Earth Sciences, University of Southern California, 3651 Trousdale Parkway, Los Angeles, CA 90089, USA
A. Joshua West
Department of Earth Sciences, University of Southern California, 3651 Trousdale Parkway, Los Angeles, CA 90089, USA
Dominic Hildebrandt
Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333 Munich, Germany
Kathrin Strößner
Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333 Munich, Germany
Kenneth A. Farley
Division of Geological and Planetary Sciences, California Institute of Technology, MC 100-23, 1200 E California Blvd, Pasadena, CA 91125,
USA
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Short summary
We use microCT scanning to improve the quality of 3He exposure ages measured in detrital magnetite. We show that the presence of inclusions can significantly increase the measured amount of 3He and thereby the exposure age. By prescreening magnetite with microCT and analyzing only inclusion-free grains, this problem can be avoided. We also calibrate the cosmogenic 3He production rate in magnetite relative to 10Be in quartz, which can be used for similar studies in the future.
We use microCT scanning to improve the quality of 3He exposure ages measured in detrital...
