Dislocations in minerals: Fast-diffusion pathways or trace-element traps?
Element mobility is a critical component in all geological processes and understanding the mechanisms responsible for element mobility in minerals is a fundamental requirement for many geochemical and geochronological applications. Volume diffusion of elements is a commonly assumed process. However,...
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| Format: | Journal Article |
| Language: | English |
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ELSEVIER
2022
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| Online Access: | http://purl.org/au-research/grants/arc/DP210102625 http://hdl.handle.net/20.500.11937/91635 |
| _version_ | 1848765564905848832 |
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| author | Verberne, R. Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Quadir, Z. Evans, Noreen Clark, Chris |
| author_facet | Verberne, R. Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Quadir, Z. Evans, Noreen Clark, Chris |
| author_sort | Verberne, R. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Element mobility is a critical component in all geological processes and understanding the mechanisms responsible for element mobility in minerals is a fundamental requirement for many geochemical and geochronological applications. Volume diffusion of elements is a commonly assumed process. However, linear defects (dislocations) are an essential component of the high-temperature creep of minerals. These defects are commonly inferred to form fast-diffusion pathways along which trace elements can more rapidly migrate. In contrast, dislocations in minerals are also energetically favourable sites of trace element segregation, which counters the notion that they enhance bulk diffusion rates by a pipe diffusion mechanism. In this paper we characterize the trace-element composition of dislocations on twin boundaries in rutile by combining atom probe tomography with transmission electron microscopy. First, morphology and correlative microstructural data are used to demonstrate that the linear compositional features in the atom probe tomography dataset represent dislocations. Assessment of dislocation composition indicates that segregation is trace element specific. The data show that dislocations in rutile act as both, fast-diffusion pathway and trace-element traps which potentially leads to erroneous estimations of the composition. |
| first_indexed | 2025-11-14T11:37:16Z |
| format | Journal Article |
| id | curtin-20.500.11937-91635 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:37:16Z |
| publishDate | 2022 |
| publisher | ELSEVIER |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-916352023-05-18T08:00:59Z Dislocations in minerals: Fast-diffusion pathways or trace-element traps? Verberne, R. Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Quadir, Z. Evans, Noreen Clark, Chris Science & Technology Physical Sciences Geochemistry & Geophysics twin boundaries dislocations atom probe tomography diffusion CRYSTAL-PLASTIC DEFORMATION GRAIN-BOUNDARY DIFFUSION ATOMIC-STRUCTURE TEMPERATURE METAMORPHISM FORMATION MECHANISM EAST ANTARCTICA RUTILE TWINS PB GEOCHRONOLOGY SEGREGATION Element mobility is a critical component in all geological processes and understanding the mechanisms responsible for element mobility in minerals is a fundamental requirement for many geochemical and geochronological applications. Volume diffusion of elements is a commonly assumed process. However, linear defects (dislocations) are an essential component of the high-temperature creep of minerals. These defects are commonly inferred to form fast-diffusion pathways along which trace elements can more rapidly migrate. In contrast, dislocations in minerals are also energetically favourable sites of trace element segregation, which counters the notion that they enhance bulk diffusion rates by a pipe diffusion mechanism. In this paper we characterize the trace-element composition of dislocations on twin boundaries in rutile by combining atom probe tomography with transmission electron microscopy. First, morphology and correlative microstructural data are used to demonstrate that the linear compositional features in the atom probe tomography dataset represent dislocations. Assessment of dislocation composition indicates that segregation is trace element specific. The data show that dislocations in rutile act as both, fast-diffusion pathway and trace-element traps which potentially leads to erroneous estimations of the composition. 2022 Journal Article http://hdl.handle.net/20.500.11937/91635 10.1016/j.epsl.2022.117517 English http://purl.org/au-research/grants/arc/DP210102625 http://purl.org/au-research/grants/arc/DE190101307 ELSEVIER restricted |
| spellingShingle | Science & Technology Physical Sciences Geochemistry & Geophysics twin boundaries dislocations atom probe tomography diffusion CRYSTAL-PLASTIC DEFORMATION GRAIN-BOUNDARY DIFFUSION ATOMIC-STRUCTURE TEMPERATURE METAMORPHISM FORMATION MECHANISM EAST ANTARCTICA RUTILE TWINS PB GEOCHRONOLOGY SEGREGATION Verberne, R. Reddy, Steven Saxey, David Fougerouse, Denis Rickard, William Quadir, Z. Evans, Noreen Clark, Chris Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title | Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title_full | Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title_fullStr | Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title_full_unstemmed | Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title_short | Dislocations in minerals: Fast-diffusion pathways or trace-element traps? |
| title_sort | dislocations in minerals: fast-diffusion pathways or trace-element traps? |
| topic | Science & Technology Physical Sciences Geochemistry & Geophysics twin boundaries dislocations atom probe tomography diffusion CRYSTAL-PLASTIC DEFORMATION GRAIN-BOUNDARY DIFFUSION ATOMIC-STRUCTURE TEMPERATURE METAMORPHISM FORMATION MECHANISM EAST ANTARCTICA RUTILE TWINS PB GEOCHRONOLOGY SEGREGATION |
| url | http://purl.org/au-research/grants/arc/DP210102625 http://purl.org/au-research/grants/arc/DP210102625 http://hdl.handle.net/20.500.11937/91635 |