The nelsonian stage: A new early triassic local stage for new zealand

Abstract

A new stage, herein named the Nelsonian Stage, is formally defined for sparsely fossiliferous New Zealand sequences of Early Triassic age. In terms of the local New Zealand stage scheme, the Nelsonian Stage is part of the Gore Series and occurs above the Late Permian Makarewan Stage and below the Middle Triassic Malakovian Stage. The base of the Nelsonian Stage is defined by the first appearance of the ammonoid Durvilleoceras within sequences of the Maitai Group that are exposed in the Nelson and Southland regions of the South Island of New Zealand. The Nelsonian Stage is attributed a middle Induan to early Anisian age range in terms of global stages, and represents a time‐span of about eight million years. © 2003 Taylor & Francis Group, LLC.