The aeromagnetic expression of New Zealand’s Alpine Fault: regional displacement and entrainment of igneous rock.
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| Title: | The aeromagnetic expression of New Zealand’s Alpine Fault: regional displacement and entrainment of igneous rock. |
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| Authors: | Rattenbury, Mark S.1 m.rattenbury@gns.cri.nz, Vidanovich, Paul2 |
| Source: | New Zealand Journal of Geology & Geophysics. Sep2018, Vol. 61 Issue 3, p272-282. 11p. 3 Charts, 4 Maps. |
| Subjects: | Geomagnetic maps, Fault zones |
| Abstract: | The Alpine Fault is very well delineated by recent high-resolution aeromagnetic data sets over much of its length in New Zealand’s South Island. Aeromagnetic data acquired over parts of the West Coast, Tasman and Marlborough regions for the New Zealand Government reveal different types of total magnetic intensity anomalies associated with the fault that can be characterised as truncated, step, ridge, trough and broad anomalies. Fault-terminated Permian ultramafic rocks, Late Cretaceous basalt and some Early Cretaceous intrusions are attributed to the more prominent truncated anomalies. The pre-eminent step anomaly is associated with relatively magnetic Alpine Schist juxtaposed against variable but generally less magnetic Western Province rocks. Strongly positive ridge anomalies occurring in the Alpine Fault zone are associated with Mesozoic mafic metavolcanic and ultramafic rocks. A trough anomaly associated with the Alpine Fault occurs in the southernmost survey and may reflect some hydrothermal demagnetisation. Broad, low-amplitude anomalies underlying the hanging wall are attributed in one instance to the extension of the magnetic Hohonu Range granitoids and dikes extending southeast in the footwall and in other places as magnetic schist rocks in the hanging wall. The apparent great-circle displacement of the Alpine Fault based on offset of magnetic anomalies associated with the Dun Mountain Ultramafics Group rocks is c. 461 km, in close agreement with the more precise 459 km inferred from geological map offset. [ABSTRACT FROM AUTHOR] |
| Copyright of New Zealand Journal of Geology & Geophysics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Engineering Source |
| FullText | Text: Availability: 0 |
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| Header | DbId: egs DbLabel: Engineering Source An: 131837669 AccessLevel: 6 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 0 |
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| Items | – Name: Title Label: Title Group: Ti Data: The aeromagnetic expression of New Zealand’s Alpine Fault: regional displacement and entrainment of igneous rock. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Rattenbury%2C+Mark+S%2E%22">Rattenbury, Mark S.</searchLink><relatesTo>1</relatesTo><i> m.rattenbury@gns.cri.nz</i><br /><searchLink fieldCode="AR" term="%22Vidanovich%2C+Paul%22">Vidanovich, Paul</searchLink><relatesTo>2</relatesTo> – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22New+Zealand+Journal+of+Geology+%26+Geophysics%22">New Zealand Journal of Geology & Geophysics</searchLink>. Sep2018, Vol. 61 Issue 3, p272-282. 11p. 3 Charts, 4 Maps. – Name: Subject Label: Subjects Group: Su Data: <searchLink fieldCode="DE" term="%22Geomagnetic+maps%22">Geomagnetic maps</searchLink><br /><searchLink fieldCode="DE" term="%22Fault+zones%22">Fault zones</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: The Alpine Fault is very well delineated by recent high-resolution aeromagnetic data sets over much of its length in New Zealand’s South Island. Aeromagnetic data acquired over parts of the West Coast, Tasman and Marlborough regions for the New Zealand Government reveal different types of total magnetic intensity anomalies associated with the fault that can be characterised as truncated, step, ridge, trough and broad anomalies. Fault-terminated Permian ultramafic rocks, Late Cretaceous basalt and some Early Cretaceous intrusions are attributed to the more prominent truncated anomalies. The pre-eminent step anomaly is associated with relatively magnetic Alpine Schist juxtaposed against variable but generally less magnetic Western Province rocks. Strongly positive ridge anomalies occurring in the Alpine Fault zone are associated with Mesozoic mafic metavolcanic and ultramafic rocks. A trough anomaly associated with the Alpine Fault occurs in the southernmost survey and may reflect some hydrothermal demagnetisation. Broad, low-amplitude anomalies underlying the hanging wall are attributed in one instance to the extension of the magnetic Hohonu Range granitoids and dikes extending southeast in the footwall and in other places as magnetic schist rocks in the hanging wall. The apparent great-circle displacement of the Alpine Fault based on offset of magnetic anomalies associated with the Dun Mountain Ultramafics Group rocks is c. 461 km, in close agreement with the more precise 459 km inferred from geological map offset. [ABSTRACT FROM AUTHOR] – Name: AbstractSuppliedCopyright Label: Group: Ab Data: <i>Copyright of New Zealand Journal of Geology & Geophysics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.) |
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| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1080/00288306.2018.1464031 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 11 StartPage: 272 Subjects: – SubjectFull: Geomagnetic maps Type: general – SubjectFull: Fault zones Type: general Titles: – TitleFull: The aeromagnetic expression of New Zealand’s Alpine Fault: regional displacement and entrainment of igneous rock. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Rattenbury, Mark S. – PersonEntity: Name: NameFull: Vidanovich, Paul IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 09 Text: Sep2018 Type: published Y: 2018 Identifiers: – Type: issn-print Value: 00288306 Numbering: – Type: volume Value: 61 – Type: issue Value: 3 Titles: – TitleFull: New Zealand Journal of Geology & Geophysics Type: main |
| ResultId | 1 |
