A NEW SUITE OF LATE TRIASSIC FISH MICROFOSSILS FROM THE NORIAN STAGE (LATE TRIASSIC) IN SOUTHLAND, NEW ZEALAND AND A MORPHOMETRIC ANALYSIS OF DIETARY PREFERENCE

2019 ◽  
Author(s):  
Deron Zierer ◽  
◽  
Lydia S. Tackett ◽  
Annaka M. Clement
Keyword(s):  
New Zealand ◽  
Morphometric Analysis ◽  
Late Triassic ◽  
Dietary Preference

A morphometric approach supporting genetic results in the taxonomy of the New Zealand limpets of the Cellana strigilis complex (Mollusca : Patellogastropoda : Nacellidae)

2012 ◽  
Vol 26 (2) ◽  
pp. 193 ◽  
Author(s):  
Céline M. O. Reisser ◽  
Bruce A. Marshall ◽  
Jonathan P. A. Gardner
Keyword(s):  
New Zealand ◽  
Red Sea ◽  
Morphometric Analysis ◽  
Type Locality ◽  
Group A ◽  
Eastern Species ◽  
Genetic Results

The New Zealand Cellana strigilis complex has been traditionally divided into six subspecies. Recent molecular investigations, however, revealed that the complex comprises two clades. In this paper, an additional morphometric analysis on 160 shells from the two clades confirms the need for taxonomic reconsideration of the C. strigilis complex. Here, two species are recognised in the Cellana strigilis group, a western species, C. strigilis (Hombron & Jacquinot, 1841), from South, Stewart, Snares, Auckland and Campbell islands, with Patella redimiculum Reeve, 1854 and C. strigilis flemingi Powell, 1955 as synonyms; and an eastern species, C. oliveri Powell, 1955, from Chatham, Bounty Islands and Antipodes Islands, with C. strigilis bollonsi Powell, 1955 and C. chathamensis of authors (not Pilsbry, 1891) as synonyms. Acmaea chathamensis Pilsbry, 1891 is based on mislocalised foreign shells, probably C. rota (Gmelin, 1791) from the Red Sea. A neotype is designated for P. strigilis Hombron & Jacquinot, 1841, lectotypes are designated for P. redimiculum Reeve, 1854 and A. chathamensis Pilsbry, 1891, and a type locality is selected for P. redimiculum.

Late Triassic plant microfossils from Miers Bluff Formation of Livingston Island, South Shetland Islands, Antarctica

2000 ◽  
Vol 12 (2) ◽  
pp. 217-228 ◽  
Author(s):  
Ouyang Shu ◽  
Deng Xi-Guang ◽  
Shen Yan-Bin ◽  
Zheng Xiang-Shen ◽  
Liu Xiao-Han
Keyword(s):  
New Zealand ◽  
Late Triassic ◽  
South Shetland Islands ◽  
Shetland Islands ◽  
Livingston Island ◽  
Plant Microfossils

A moderately diverse assemblage of plant microfossils has been recovered from the Johnsons Dock Member of the Miers Bluff Formation, Livingston Island, including spores, pollen, acritarchs, wood fragments and cuticles. Containing a total of c. 45 of miospore taxa, the palynoflora is dominated by non-striate bisaccate pollen, but spores of pteridophytes and pollen of gymnosperms are proportionate in diversity. The palynoflora is similar in composition to those indicative of subzones C + D of the Alisporites Zone of Antarctica, and the upper Craterisporites rotundus Zone and the lower Polycingulatisporites crenulatus Zone of Australia as well as the upper Polycingulatisporites crenulatus Zone and Foveosporites moretonensis Zone of New Zealand, suggesting a Late Triassic (possibly Norian–Rhaetian) age. This determination is supported by the sporadic occurrence of Aratrisporites and Classopollis in the palynoflora as well as by the absence of striate bisaccate grains.

scholarly journals Sedimentology and depositional environments of Murihiku Supergroup sediments exposed in the Southland Syncline, New Zealand: Implications for reservoir potential in the Great South Basin

2021 ◽  
Author(s):  
◽  
Angus David Howden
Keyword(s):  
New Zealand ◽  
Middle Jurassic ◽  
Petroleum Industry ◽  
Depositional Environments ◽  
Seismic Facies ◽  
Late Triassic ◽  
Petrographic Composition ◽  
South Basin ◽  
Porosity And Permeability ◽  
Reservoir Potential

<p>A considerable amount is known about the biostratigraphy and organic geochemistry of the Murihiku Supergroup sediments exposed in coastal outcrops of the Southland Syncline, New Zealand. Much less work has been undertaken on the sedimentology of these strata, or understanding their depositional environments and depositional trends through time. What these implications are for reservoir prospectivity in the adjacent Great South Basin, has also had little study focused on it.  This thesis addresses these issues by undertaking outcrop-based sedimentological and facies interpretations of these rocks, thin-section based petrographic composition and provenance analysis, augmented by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM), as well as porosity and permeability measurements from outcrop core plugs. Petroleum industry seismic data has additionally enabled seismic facies mapping of Murihiku rocks in the offshore Great South Basin.  Outcrop observations point to a progressive change in depositional setting, from shelf / upper slope settings during the Late Triassic, to base of slope turbidite deposition in the Early Jurassic. This transgression is followed by regression into fluvial settings in the youngest outcropping Murihiku rocks in the study of Middle Jurassic age. Petrographically the sandstones are feldspathic and lithic arenites and feldspathic and lithic wackes. Provenance suggests derivation from an evolving, intermediate arc that was becoming more siliceous through Late Triassic and Middle Jurassic time. Diagenesis is characterised by early calcite and chlorite precipitation which have almost completely destroyed any primary porosity. Any secondary micro porosity has subsequently been infilled through dissolution of framework grains and zeolitization. SEM and core plug porosity and permeability measurements corroborate the diagenetic changes observed petrographically, with only fluvial facies of Middle Jurassic (Upper Temaikan) age showing any measureable porosity or permeability.  As a result, reservoir potential for the Late Triassic to Middle Jurassic, Murihiku Supergroup rocks analysed in this study is low. Younger Murihiku sandstones which are postulated to occur offshore in the Great South Basin are likely to be less influenced by burial diagenesis. As shown from North Island occurrences, these younger successions hold some potential.The reservoir potential for these youngest portions of the Murihiku succession therefore remains positive, both in the Great South Basin, as well as other frontier areas of Zealandia, and continue to provide an exploration target for the petroleum industry.</p>

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