Magmatism during Gondwana break-up: new geochronological data from Westland, New Zealand
- Newly determined Late Cretaceous Ar-40/Ar-39 ages on megacrystic kaersutite from four lamprophyre dikes, and a U-Pb zircon age on a trachyte, from central and north Westland (New Zealand) are presented. These ages suggest that the intrusion of mafic dikes (88-86 and 69 Ma) was not necessarily restricted to the previously established narrow age range of 80-92 Ma. The younger lamprophyre and trachyte dikes (c. 68-70 Ma) imply that tensional stresses in the Western Province were either renewed at this time, or that extension and related magmatism continued during opening of the Tasman Sea. Extension-related magmatism in the region not only preceded Tasman seafloor spreading initiation (starting at c. 83 Ma, lasting to c. 53 Ma), but may have sporadically continued for up to 15 Ma after continental break-up.
| Author details: | Q. H. A. Van der Meer, James M. Scott, T. E. Waight, Masafumi SudoORCiDGND, A. Schersten, Alan F. Cooper, Terry L. Spell |
|---|---|
| DOI: | https://doi.org/10.1080/00288306.2013.826699 |
| ISSN: | 0028-8306 |
| ISSN: | 1175-8791 |
| Title of parent work (English): | New Zealand journal of geology and geophysics : an international journal of pacific rim geosciences |
| Publisher: | Routledge, Taylor & Francis Group |
| Place of publishing: | Abingdon |
| Publication type: | Article |
| Language: | English |
| Year of first publication: | 2013 |
| Publication year: | 2013 |
| Release date: | 2017/03/26 |
| Tag: | Fraser Complex; Gondwana break-up; central Westland; geochronology; lamprophyre |
| Volume: | 56 |
| Issue: | 4 |
| Number of pages: | 14 |
| First page: | 229 |
| Last Page: | 242 |
| Funding institution: | FRST [UOX1004]; Danish Research Council for Nature and Universe; QHAVDM [10-085245] |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Biochemie und Biologie |
| Peer review: | Referiert |
