Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy
Field and petrographic observations combined with major and trace element bulk rock geochemistry show that metabasic rocks within Val Strona di Omegna in the central Ivrea Zone partially melted during granulite facies regional metamorphism. A transition from granoblastic amphibolite facies metabasic...
| Main Authors: | , , , |
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| Format: | Journal Article |
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Elsevier BV
2014
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| Online Access: | http://hdl.handle.net/20.500.11937/14040 |
| _version_ | 1848748513303724032 |
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| author | Kunz, B. Johnson, Tim White, R. Redler, C. |
| author_facet | Kunz, B. Johnson, Tim White, R. Redler, C. |
| author_sort | Kunz, B. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Field and petrographic observations combined with major and trace element bulk rock geochemistry show that metabasic rocks within Val Strona di Omegna in the central Ivrea Zone partially melted during granulite facies regional metamorphism. A transition from granoblastic amphibolite facies metabasic rocks at the lowest metamorphic grades to metatexitic and diatexitic migmatites in the granulite facies records the effects of in situ fluid-absent partial melting. Coarse-grained euhedral clinopyroxene porphyroblasts within leucosomes are consistent with anatexis via incongruent fluid-absent melting reactions consuming hornblende, plagioclase and quartz to form clinopyroxene and melt. Field observations are supported by bulk rock geochemistry, in which high-grade samples are generally depleted in mobile elements relative to unmigmatised mid amphibolite facies rocks that may approximate pre-melting protolith compositions. Many of the metabasic rocks at the highest-grade parts of Val Strona di Omegna probably belong to the Kinzigite Formation and are unlikely to be part of the younger Mafic Complex as previously proposed. |
| first_indexed | 2025-11-14T07:06:14Z |
| format | Journal Article |
| id | curtin-20.500.11937-14040 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:06:14Z |
| publishDate | 2014 |
| publisher | Elsevier BV |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-140402019-02-19T04:25:43Z Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy Kunz, B. Johnson, Tim White, R. Redler, C. In situ partial melting Ivrea Zone Granulite facies regional metamorphism Metabasic rocks Field and petrographic observations combined with major and trace element bulk rock geochemistry show that metabasic rocks within Val Strona di Omegna in the central Ivrea Zone partially melted during granulite facies regional metamorphism. A transition from granoblastic amphibolite facies metabasic rocks at the lowest metamorphic grades to metatexitic and diatexitic migmatites in the granulite facies records the effects of in situ fluid-absent partial melting. Coarse-grained euhedral clinopyroxene porphyroblasts within leucosomes are consistent with anatexis via incongruent fluid-absent melting reactions consuming hornblende, plagioclase and quartz to form clinopyroxene and melt. Field observations are supported by bulk rock geochemistry, in which high-grade samples are generally depleted in mobile elements relative to unmigmatised mid amphibolite facies rocks that may approximate pre-melting protolith compositions. Many of the metabasic rocks at the highest-grade parts of Val Strona di Omegna probably belong to the Kinzigite Formation and are unlikely to be part of the younger Mafic Complex as previously proposed. 2014 Journal Article http://hdl.handle.net/20.500.11937/14040 10.1016/j.lithos.2013.11.015 Elsevier BV fulltext |
| spellingShingle | In situ partial melting Ivrea Zone Granulite facies regional metamorphism Metabasic rocks Kunz, B. Johnson, Tim White, R. Redler, C. Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title | Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title_full | Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title_fullStr | Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title_full_unstemmed | Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title_short | Partial melting of metabasic rocks in Val Strona di Omegna, Ivrea Zone, northern Italy |
| title_sort | partial melting of metabasic rocks in val strona di omegna, ivrea zone, northern italy |
| topic | In situ partial melting Ivrea Zone Granulite facies regional metamorphism Metabasic rocks |
| url | http://hdl.handle.net/20.500.11937/14040 |