Feldspar Ar-40/(39) Ar dating of ICDP PALEOVAN cores
- Eleven inverse isochron ages from total fusion and three from stepwise heating analyses fit the age model. Four experiments resulted in older inverse isochron ages that do not concur with the model within 2 sigma uncertainties and that deviate from 1 ka to 17 ka minimum. C-and R-type zoning are interpreted as representing growth in magma chamber cupolas, as wall mushes, or in narrow conduits. Persistent compositions of PO-type crystals and abundant surfaces recording dissolution features correspond to formation within a magma chamber. C-type zoning and R-type zoning have revealed an irregular incorporation of melt and fluid inclusions. These two types of zoning in feldspar are interpreted as preferentially contributing either heterogeneously distributed excess Ar-40 or inherited Ar-40 to the deviating Ar-40/Ar-39 ages that are discussed in this study. (C) 2017 Elsevier Ltd. All rights reserved.
Author details: | Jonathan Franz Engelhardt, Masafumi SudoORCiDGND, Mona Stockhecke, Roland Oberhaensli |
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DOI: | https://doi.org/10.1016/j.gca.2017.07.039 |
ISSN: | 0016-7037 |
ISSN: | 1872-9533 |
Title of parent work (English): | Geochimica et cosmochimica acta : journal of the Geochemical Society and the Meteoritical Society |
Publisher: | Elsevier |
Place of publishing: | Oxford |
Publication type: | Article |
Language: | English |
Year of first publication: | 2017 |
Publication year: | 2017 |
Release date: | 2020/04/20 |
Tag: | Feldspar zoning; Lacustrine record; Lake Van; Volcaniclastics |
Volume: | 217 |
Number of pages: | 27 |
First page: | 144 |
Last Page: | 170 |
RVK - Regensburg classification: | TK 1010 |
Funding institution: | International Continental Scientific Drilling Program (ICDP); Deutsche Forschungsgemeinschaft (DFG) [OB80/48-1] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
Peer review: | Referiert |
Institution name at the time of the publication: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Erd- und Umweltwissenschaften |