Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications

Volcanic ash (tephra) horizons represent powerful chronological and stratigraphic markers: rapid and widespread deposition allows for correlation of geological records in time and space. Recent analytical advances enable identification of invisible ash (cryptotephra) up to thousands of kilometers fr...

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Published in:Frontiers in Earth Science
Main Authors: Willem G. M. van der Bilt, Jan Magne Cederstrøm, Eivind W. N. Støren, Sarah M. P. Berben, Sunniva Rutledal
Format: Article in Journal/Newspaper
Language:English
Published: Frontiers Media S.A. 2021
Subjects:
Q
Online Access:https://doi.org/10.3389/feart.2020.622386
https://doaj.org/article/2dc97fd0499b46e89da6fbe27d14691e
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spelling ftdoajarticles:oai:doaj.org/article:2dc97fd0499b46e89da6fbe27d14691e 2023-05-15T16:39:20+02:00 Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications Willem G. M. van der Bilt Jan Magne Cederstrøm Eivind W. N. Støren Sarah M. P. Berben Sunniva Rutledal 2021-01-01T00:00:00Z https://doi.org/10.3389/feart.2020.622386 https://doaj.org/article/2dc97fd0499b46e89da6fbe27d14691e EN eng Frontiers Media S.A. https://www.frontiersin.org/articles/10.3389/feart.2020.622386/full https://doaj.org/toc/2296-6463 2296-6463 doi:10.3389/feart.2020.622386 https://doaj.org/article/2dc97fd0499b46e89da6fbe27d14691e Frontiers in Earth Science, Vol 8 (2021) tephra synthetic cores (phantoms) CT X-ray peat minerogenic ice core Science Q article 2021 ftdoajarticles https://doi.org/10.3389/feart.2020.622386 2022-12-31T12:25:22Z Volcanic ash (tephra) horizons represent powerful chronological and stratigraphic markers: rapid and widespread deposition allows for correlation of geological records in time and space. Recent analytical advances enable identification of invisible ash (cryptotephra) up to thousands of kilometers from its volcanic source. This momentum has greatly expanded the reach and potential of tephrochronology: some deposits can now be traced across continents and oceans. However, the laborious laboratory procedures required to identify tephra horizons in geological archives hold back the pace of progress. By allowing the rapid visualization of ash at micrometer (µm) scales, computed tomography (CT) holds great promise to overcome these restrictions. In this study, we further demonstrate the potential of this tool for the tephra community with experimental results and applications on conventionally analyzed archives. A custom-made scanner helps us strike a balance between the convenience of whole-core medical scanners and the µm-resolution of micro-CT systems. Using basic image processing tools that can be readily mastered by tephrochronologists, we identified invisible horizons down to ∼500 shards in synthetic cores. In addition, procedures for the removal of image artifacts can be used to visualize other paleoenvironmental indicators such as bioturbation burrows, ice rafted debris or mineral dust. When applied on segments of manually counted natural archives, our approach captures cryptic glass shard maxima down to ∼300 shards/cm3. We also highlight the value of CT to help optimize sampling strategies by identifying micrometer-scale ash horizons that were not detected in shard count profiles. In conclusion, this work helps broaden the applicability of CT as a promising frontier in tephrochronology that can advance the field by optimizing the efficiency and accuracy of isochron detection. Article in Journal/Newspaper ice core Directory of Open Access Journals: DOAJ Articles Burrows ENVELOPE(163.650,163.650,-74.300,-74.300) Frontiers in Earth Science 8
institution Open Polar
collection Directory of Open Access Journals: DOAJ Articles
op_collection_id ftdoajarticles
language English
topic tephra
synthetic cores (phantoms)
CT X-ray
peat
minerogenic
ice core
Science
Q
spellingShingle tephra
synthetic cores (phantoms)
CT X-ray
peat
minerogenic
ice core
Science
Q
Willem G. M. van der Bilt
Jan Magne Cederstrøm
Eivind W. N. Støren
Sarah M. P. Berben
Sunniva Rutledal
Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
topic_facet tephra
synthetic cores (phantoms)
CT X-ray
peat
minerogenic
ice core
Science
Q
description Volcanic ash (tephra) horizons represent powerful chronological and stratigraphic markers: rapid and widespread deposition allows for correlation of geological records in time and space. Recent analytical advances enable identification of invisible ash (cryptotephra) up to thousands of kilometers from its volcanic source. This momentum has greatly expanded the reach and potential of tephrochronology: some deposits can now be traced across continents and oceans. However, the laborious laboratory procedures required to identify tephra horizons in geological archives hold back the pace of progress. By allowing the rapid visualization of ash at micrometer (µm) scales, computed tomography (CT) holds great promise to overcome these restrictions. In this study, we further demonstrate the potential of this tool for the tephra community with experimental results and applications on conventionally analyzed archives. A custom-made scanner helps us strike a balance between the convenience of whole-core medical scanners and the µm-resolution of micro-CT systems. Using basic image processing tools that can be readily mastered by tephrochronologists, we identified invisible horizons down to ∼500 shards in synthetic cores. In addition, procedures for the removal of image artifacts can be used to visualize other paleoenvironmental indicators such as bioturbation burrows, ice rafted debris or mineral dust. When applied on segments of manually counted natural archives, our approach captures cryptic glass shard maxima down to ∼300 shards/cm3. We also highlight the value of CT to help optimize sampling strategies by identifying micrometer-scale ash horizons that were not detected in shard count profiles. In conclusion, this work helps broaden the applicability of CT as a promising frontier in tephrochronology that can advance the field by optimizing the efficiency and accuracy of isochron detection.
format Article in Journal/Newspaper
author Willem G. M. van der Bilt
Jan Magne Cederstrøm
Eivind W. N. Støren
Sarah M. P. Berben
Sunniva Rutledal
author_facet Willem G. M. van der Bilt
Jan Magne Cederstrøm
Eivind W. N. Støren
Sarah M. P. Berben
Sunniva Rutledal
author_sort Willem G. M. van der Bilt
title Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
title_short Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
title_full Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
title_fullStr Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
title_full_unstemmed Rapid Tephra Identification in Geological Archives With Computed Tomography: Experimental Results and Natural Applications
title_sort rapid tephra identification in geological archives with computed tomography: experimental results and natural applications
publisher Frontiers Media S.A.
publishDate 2021
url https://doi.org/10.3389/feart.2020.622386
https://doaj.org/article/2dc97fd0499b46e89da6fbe27d14691e
long_lat ENVELOPE(163.650,163.650,-74.300,-74.300)
geographic Burrows
geographic_facet Burrows
genre ice core
genre_facet ice core
op_source Frontiers in Earth Science, Vol 8 (2021)
op_relation https://www.frontiersin.org/articles/10.3389/feart.2020.622386/full
https://doaj.org/toc/2296-6463
2296-6463
doi:10.3389/feart.2020.622386
https://doaj.org/article/2dc97fd0499b46e89da6fbe27d14691e
op_doi https://doi.org/10.3389/feart.2020.622386
container_title Frontiers in Earth Science
container_volume 8
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