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.

Metadaten
Verfasserangaben:	Q. H. A. Van der Meer, James M. Scott, T. E. Waight, Masafumi Sudo ORCiD GND, A. Schersten, Alan F. Cooper, Terry L. Spell
DOI:	https://doi.org/10.1080/00288306.2013.826699
ISSN:	0028-8306
ISSN:	1175-8791
Titel des übergeordneten Werks (Englisch):	New Zealand journal of geology and geophysics : an international journal of pacific rim geosciences
Verlag:	Routledge, Taylor & Francis Group
Verlagsort:	Abingdon
Publikationstyp:	Wissenschaftlicher Artikel
Sprache:	Englisch
Jahr der Erstveröffentlichung:	2013
Erscheinungsjahr:	2013
Datum der Freischaltung:	26.03.2017
Freies Schlagwort / Tag:	Fraser Complex; Gondwana break-up; central Westland; geochronology; lamprophyre
Band:	56
Ausgabe:	4
Seitenanzahl:	14
Erste Seite:	229
Letzte Seite:	242
Fördernde Institution:	FRST [UOX1004]; Danish Research Council for Nature and Universe; QHAVDM [10-085245]
Organisationseinheiten:	Mathematisch-Naturwissenschaftliche Fakultät / Institut für Biochemie und Biologie
Peer Review:	Referiert