The geochemical and geochronological implications of nanoscale trace-element clusters in rutile
© 2020. All rights reserved. The geochemical analysis of trace elements in rutile (e.g., Pb, U, and Zr) is routinely used to extract information on the nature and timing of geological events. However, the mobility of trace elements can affect age and temperature determinations, with the contro...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
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GEOLOGICAL SOC AMER, INC
2020
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| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/82054 |
| _version_ | 1848764466432311296 |
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| author | Verberne, Rick Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Plavsa, D. Agangi, Andrea Kylander-Clark, A.R.C. |
| author_facet | Verberne, Rick Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Plavsa, D. Agangi, Andrea Kylander-Clark, A.R.C. |
| author_sort | Verberne, Rick |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | © 2020. All rights reserved.
The geochemical analysis of trace elements in rutile (e.g., Pb, U, and Zr) is routinely used to extract information on the nature and timing of geological events. However, the mobility of trace elements can affect age and temperature determinations, with the controlling mecha-nisms for mobility still debated. To further this debate, we use laser-ablation-inductively coupled plasma-mass spectrometry and atom probe tomography to characterize the micro- to nanoscale distribution of trace elements in rutile sourced from the Capricorn orogen, Western Australia. At the >20 pm scale, there is no significant trace-element variation in single grains, and a concordant U-Pb crystallization age of 1872 ± 6 Ma (2a) shows no evidence of isotopic disturbance. At the nanoscale, clusters as much as 20 nm in size and enriched in trace ele-ments (Al, Cr, Pb, and V) are observed. The 207Pb/206Pb ratio of 0.176 ± 0.040 (2a) obtained from clusters indicates that they formed after crystallization, potentially during regional metamorphism. We interpret the clusters to have formed by the entrapment of mobile trace elements in transient sites of radiation damage during upper amphibolite facies metamor-phism. The entrapment would affect the activation energy for volume diffusion of elements present in the cluster. The low number and density of clusters provides constraints on the time over which clusters formed, indicating that peak metamorphic temperatures are short-lived, <10 m.y. events. Our results indicate that the use of trace elements to estimate volume diffusion in rutile is more complex than assuming a homogeneous medium. |
| first_indexed | 2025-11-14T11:19:48Z |
| format | Journal Article |
| id | curtin-20.500.11937-82054 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:19:48Z |
| publishDate | 2020 |
| publisher | GEOLOGICAL SOC AMER, INC |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-820542021-03-23T02:30:23Z The geochemical and geochronological implications of nanoscale trace-element clusters in rutile Verberne, Rick Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Plavsa, D. Agangi, Andrea Kylander-Clark, A.R.C. Science & Technology Physical Sciences Geology ATOM-PROBE METAMORPHIC RUTILE PB ZIRCON TEMPERATURE AGE TIO2 © 2020. All rights reserved. The geochemical analysis of trace elements in rutile (e.g., Pb, U, and Zr) is routinely used to extract information on the nature and timing of geological events. However, the mobility of trace elements can affect age and temperature determinations, with the controlling mecha-nisms for mobility still debated. To further this debate, we use laser-ablation-inductively coupled plasma-mass spectrometry and atom probe tomography to characterize the micro- to nanoscale distribution of trace elements in rutile sourced from the Capricorn orogen, Western Australia. At the >20 pm scale, there is no significant trace-element variation in single grains, and a concordant U-Pb crystallization age of 1872 ± 6 Ma (2a) shows no evidence of isotopic disturbance. At the nanoscale, clusters as much as 20 nm in size and enriched in trace ele-ments (Al, Cr, Pb, and V) are observed. The 207Pb/206Pb ratio of 0.176 ± 0.040 (2a) obtained from clusters indicates that they formed after crystallization, potentially during regional metamorphism. We interpret the clusters to have formed by the entrapment of mobile trace elements in transient sites of radiation damage during upper amphibolite facies metamor-phism. The entrapment would affect the activation energy for volume diffusion of elements present in the cluster. The low number and density of clusters provides constraints on the time over which clusters formed, indicating that peak metamorphic temperatures are short-lived, <10 m.y. events. Our results indicate that the use of trace elements to estimate volume diffusion in rutile is more complex than assuming a homogeneous medium. 2020 Journal Article http://hdl.handle.net/20.500.11937/82054 10.1130/G48017.1 English GEOLOGICAL SOC AMER, INC fulltext |
| spellingShingle | Science & Technology Physical Sciences Geology ATOM-PROBE METAMORPHIC RUTILE PB ZIRCON TEMPERATURE AGE TIO2 Verberne, Rick Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Plavsa, D. Agangi, Andrea Kylander-Clark, A.R.C. The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title | The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title_full | The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title_fullStr | The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title_full_unstemmed | The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title_short | The geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| title_sort | geochemical and geochronological implications of nanoscale trace-element clusters in rutile |
| topic | Science & Technology Physical Sciences Geology ATOM-PROBE METAMORPHIC RUTILE PB ZIRCON TEMPERATURE AGE TIO2 |
| url | http://hdl.handle.net/20.500.11937/82054 |