The dating of volcanic tephras forms a critical cornerstone of chronostratigraphy and is paramount for the resolution of the geological timescale. (U‐Th[‐Sm])/He dating is an emerging tool in Quaternary tephrochronology and ideally suited to date tephras <1 Ma. We present zircon, magnetite and apatite (U‐Th[‐Sm])/He combined with zircon U‐Pb data for a Pleistocene tephra in syn‐rift strata of the Woodlark Rift in Papua New Guinea. The results reveal a young He age mode (~0.5 to 0.8 Ma), consistent with an autocrystic zircon U‐Pb crystallisation age of 0.8 ± 0.1 Ma, as well as a broad range of older (U‐Th[‐Sm])/He (~1.6 to 10.2 Ma) and U‐Pb (~4.4 to 107 Ma) ages. These data demonstrate the potential of integrated U‐Pb and (U‐Th[‐Sm])/He multi‐method chronometry for dating the youngest coherent age mode, detecting contaminant grains and evaluating the isotopic systematics of these techniques.
Flamenco on the Front Range
Author Mark French is walking the lutherie path in the reverse direction of many makers. As a physics prof trained in the crazy magic of CNC and industrial robot processes, he had made a lot of guitars before he did much in the way of traditional low-tech hand-tool work. As part of an intensive effort to fill in those gaps, he attended an eight-day course at Robbie O’Brien’s shop in Colorado to make a flamenco guitar with Spanish luthier and licensed bloodless toreador Paco Chorobo.
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- Award ID(s):
- 1700531
- PAR ID:
- 10156885
- Date Published:
- Journal Name:
- American lutherie
- Volume:
- 138
- ISSN:
- 1041-7176
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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