Abstract
Laser ablation inductively coupled plasma mass‐spectrometry (LA‐ICP‐MS) 206Pb‐238U zircon dates are reported for eight plutonic rocks from eastern Fiordland. The oldest samples are Jurassic (granodiorite, 160.6 ±1.4 Ma; quartz diorite, 153.0 ± 0.8 Ma; granodiorite, 152.5 ± 0.7 Ma; errors at 2 a) and collectively belong to the Hunter Intrusives member of the Darran/Median Suite. The LA‐ICP‐MS age for the younger granodiorite agrees with a concordant multigrain TIMS U‐Pb zircon age previously obtained from the same sample. Xenoliths of Hunter Intrusives occur within the Early Cretaceous (127.9 ± 1.1 Ma) granitic Fowler Pluton, also of the Darran/Median Suite. There was a short lull in plutonism until emplacement of leucogranite dikes (123.5 ± 1.2 Ma) and granitoids of the Refrigerator Orthogneiss (120.7 ± 1.1 Ma), Puteketeke Pluton (120.8 ± 0.9 Ma), and West Arm Leucogranite (116.3 ± 1.2 Ma), all of which are members of the Separation Point Suite.
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