The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar
A combination of forescatter scanning electron microscopy and both ultra-violet (UV) laser and cycle stepped-heating 40Ar/39Ar dating techniques have been applied to a single deformed grain of potassium feldspar to investigate the relationship between microstructure and 40Ar/39Ar isotope systematics...
| Main Authors: | , , , |
|---|---|
| Format: | Journal Article |
| Published: |
Geological Society of America
1999
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/31389 |
| _version_ | 1848753367038296064 |
|---|---|
| author | Reddy, Steven Potts, G. Kelley, S. Arnaud, N. |
| author_facet | Reddy, Steven Potts, G. Kelley, S. Arnaud, N. |
| author_sort | Reddy, Steven |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | A combination of forescatter scanning electron microscopy and both ultra-violet (UV) laser and cycle stepped-heating 40Ar/39Ar dating techniques have been applied to a single deformed grain of potassium feldspar to investigate the relationship between microstructure and 40Ar/39Ar isotope systematics. The form and distribution of deformation-induced microstructures has been mapped using intragrain variations in lattice orientation. These variations are related to thin section and regional structural data to provide a well-constrained deformation history for the feldspar grain. Thirty laser 40Ar/39Ar analyses show age variations that correlate with the internal microstructure. Stepped-heating data provide further evidence of this relationship. Our approach allows the recognition of different Ar reservoirs within the deformed feldspar and identifies microstructural controls on Ar migration. Such a relationship has important implications for the understanding and interpretation of 40Ar/39Ar geochronological data and the subsequent use of such data to constrain the temperature - time evolution of deformed rocks. |
| first_indexed | 2025-11-14T08:23:23Z |
| format | Journal Article |
| id | curtin-20.500.11937-31389 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:23:23Z |
| publishDate | 1999 |
| publisher | Geological Society of America |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-313892017-01-30T13:25:06Z The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar Reddy, Steven Potts, G. Kelley, S. Arnaud, N. orientation MDD Diffusion argon A combination of forescatter scanning electron microscopy and both ultra-violet (UV) laser and cycle stepped-heating 40Ar/39Ar dating techniques have been applied to a single deformed grain of potassium feldspar to investigate the relationship between microstructure and 40Ar/39Ar isotope systematics. The form and distribution of deformation-induced microstructures has been mapped using intragrain variations in lattice orientation. These variations are related to thin section and regional structural data to provide a well-constrained deformation history for the feldspar grain. Thirty laser 40Ar/39Ar analyses show age variations that correlate with the internal microstructure. Stepped-heating data provide further evidence of this relationship. Our approach allows the recognition of different Ar reservoirs within the deformed feldspar and identifies microstructural controls on Ar migration. Such a relationship has important implications for the understanding and interpretation of 40Ar/39Ar geochronological data and the subsequent use of such data to constrain the temperature - time evolution of deformed rocks. 1999 Journal Article http://hdl.handle.net/20.500.11937/31389 Geological Society of America restricted |
| spellingShingle | orientation MDD Diffusion argon Reddy, Steven Potts, G. Kelley, S. Arnaud, N. The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title | The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title_full | The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title_fullStr | The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title_full_unstemmed | The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title_short | The effects of deformation-induced microstructures on intragrain Ar(40)/Ar(39) ages in potassium feldspar |
| title_sort | effects of deformation-induced microstructures on intragrain ar(40)/ar(39) ages in potassium feldspar |
| topic | orientation MDD Diffusion argon |
| url | http://hdl.handle.net/20.500.11937/31389 |