Paleogeography of Late Eocene to earliest Miocene Te Kuiti Group, central-western North Island, New Zealand

Abstract

We present a series of 13 paleogeographic maps representing development of the Waikato-King Country Basin through the Late Eocene to Early Miocene in central-western North Island when the New Zealand platform was undergoing widespread marine inundation. The maps are the end-point of a basin analysis of the Te Kuiti Group, which has included development of a revised lithostratigraphy, biostratigraphy, chronostratigraphy and the application of facies analysis. The new stratigraphic framework has identified six major unconformity-bound sequences within the Te Kuiti Group and the paleogeographic maps are drawn for time-slices through unconformities and systems tracts. A major unconformity between the Whaingaroa Formation and the Aotea Formation dated c. 29 Ma marks the start of reverse faulting on the Taranaki Fault. At c. 27 Ma, reverse displacement on the Manganui Fault started. Several phases of displacement on the Manganui Fault ensured that land persisted over part of the Herangi High throughout the Duntroonian (Ld) and Waitakian (Lw) Stages spanning the Late Oligocene and earliest Miocene.

Biogeography of the Gondwanan tree fern family Dicksoniaceae—A tale of vicariance, dispersal and extinction

“…This finding agrees with the contemporarily favoured scenario that New Caledonia was submerged during the Palaeocene and Eocene (Grandcolas et al., ; Schellart, Lister, & Toy, ) and re‐emerged around 38–33 Ma (Grandcolas, ; Murienne et al., ). However, the current ranges of the respective sister clades are on islands that are also either too young (Fiji, Samoa, Vanuatu and the Solomon Islands) or have been submerged for most of that time (New Zealand), and thus, provides no unambiguous evidence for reconstructing the ancestral area of the entire Pacific clade (Neall & Trewick, ), although some argue that New Zealand may have never been submerged completely (Campbell & Hutching, ; Kamp, Tripathi, & Nelson, ; Landis et al., ). The Pacific clade may thus have survived in this geologically dynamic area by being able to repeatedly colonize short‐lived islands.…”

High-level stratigraphic scheme for New Zealand rocks

“…In its type area of the onshore Canterbury region, the Marshall Unconformity is middle Oligocene in age and forms a distinctive depositional break between carbonate-dominated intervals; here, Carter (1988) used it as a group boundary marking the regional transition from peak marine transgression to onset of regression. In other places however, such as in Taranaki Basin and adjacent basins to the east, peak marine inundation occurred significantly later during the latest Oligocene (Kamp et al 2014;Strogen et al 2014). Moreover, the Marshall Unconformity is not recognised everywhere, has different ages and potentially different origins and occurs variably within or beneath the overall Oligocene carbonate-dominated succession (King et al 1999;Lever 2007).…”

Oligocene paleogeography of New Zealand: maximum marine transgression

“…The combination of thick clastic sediments, including sandy turbidite units, with moderate tectonic activity on the Taranaki Fault System, during the latest Oligocene to earliest Miocene suggests an eroding sub-aerial sediment source during this time. Similarly, Kamp et al (2014) present 13 paleogeographic maps of the latest Eocene to earliest Miocene for the Waikato-King Country region. They also show that land persisted on geographic highs, particularly east of the Manganui Fault, during latest Oligocene to earliest Miocene time as a result of tectonic activity on the Taranaki and Manganui faults.…”