scholarly journals Understanding Magma Rise and Storage Using Major Element Diffusion in Olivine; Pupuke Maar, Auckland Field, New Zealand

2020 ◽  
Author(s):  
Madison Anae ◽  
Victoria Cassady ◽  
Ingrid Ukstins ◽  
Marco Brenna ◽  
Shane J Cronin ◽  
...  
Keyword(s):  
New Zealand ◽  
Major Element ◽  
Element Diffusion ◽  
And Storage

scholarly journals TephraNZ: a major and trace element reference dataset for prominent Quaternary rhyolitic tephras in New Zealand and implications for correlation

2020 ◽  
Author(s):  
Jenni L. Hopkins ◽  
Janine E. Bidmead ◽  
David J. Lowe ◽  
Richard J. Wysoczanski ◽  
Bradley J. Pillans ◽  
...  
Keyword(s):  
New Zealand ◽  
Trace Element ◽  
Major Element ◽  
Chemical Compositions ◽  
Volcanic Centre ◽  
Reference Dataset ◽  
Future Studies ◽  
Glass Shard ◽  
Tephra Deposits ◽  
Glass Shards

Abstract. Although analyses of tephra-derived glass shards have been undertaken in New Zealand for nearly four decades (pioneered by Paul Froggatt), our study is the first to systematically develop a formal, comprehensive, open access, reference dataset of glass-shard compositions for New Zealand tephras. These data will provide an important reference tool for future studies to identify and correlate tephra deposits and for associated petrological and magma-related studies within New Zealand and beyond. Here we present the foundation dataset for TephraNZ, an open access reference dataset for selected tephra deposits in New Zealand. Prominent, rhyolitic, tephra deposits from the Quaternary were identified, with sample collection targeting original type sites or reference locations where the tephra's identification is unequivocally known based on independent dating or mineralogical techniques. Glass shards were extracted from the tephra deposits and major and trace element geochemical compositions were determined. We discuss in detail the data reduction process used to obtain the results and propose that future studies follow a similar protocol in order to gain comparable data. The dataset contains analyses of twenty-three proximal and twenty-seven distal tephra samples characterising 45 eruptive episodes ranging from Kaharoa (636 ± 12 cal. yrs BP) to the Hikuroa Pumice member (2.0 ± 0.6 Ma) from six or more caldera sources, most from the central Taupō Volcanic Zone. We report 1385 major element analyses obtained by electron microprobe (EMPA), and 590 trace element analyses obtained by laser ablation (LA)-ICP-MS, on individual glass shards. Using PCA, Euclidean similarity coefficients, and geochemical investigation, we show that chemical compositions of glass shards from individual eruptions are commonly distinguished by major elements, especially CaO, TiO2, K2O, FeOt (Na2O+ K2O and SiO2/K2O), but not always. For those tephras with similar glass major-element signatures, some can be distinguished using trace elements (e.g. HFSEs: Zr, Hf, Nb; LILE: Ba, Rb; REE: Eu, Tm, Dy, Y, Tb, Gd, Er, Ho, Yb, Sm), and trace element ratios (e.g. LILE / HFSE: Ba / Th, Ba / Zr, Rb / Zr; HFSE / HREE: Zr / Y, Zr / Yb, Hf / Y; LREE / HREE: La / Yb, Ce / Yb). Geochemistry alone cannot be used to distinguish between glass shards from the following tephra groups: Taupō (Unit Y in the post-Ōruanui eruption sequence of Taupō volcano) and Waimihia (Unit S); Poronui (Unit C) and Karapiti (Unit B); Rotorua and Rerewhakaaitu; and Kawakawa/Ōruanui, Okaia, and Unit L (of the Mangaone subgroup eruption sequence). Other characteristics can be used to separate and distinguish all of these otherwise-similar eruptives except Poronui and Karapiti. Bimodality caused by K2O variability is newly identified in Poihipi and Tahuna tephras. Using glass shard compositions, tephra sourced from Taupō Volcanic Centre (TVC) and Mangakino Volcanic Centre (MgVC) can be separated using bivariate plots of SiO2/K2O vs. Na2O+K2O. Glass shards from tephras derived from Kapenga Volcanic Centre, Rotorua Volcanic Centre, and Whakamaru Volcanic Centre have similar major- and trace-element chemical compositions to those from the MgVC, but can overlap with glass analyses from tephras from Taupō and Okataina volcanic centres. Specific trace elements and trace element ratios have lower variability than the heterogeneous major element and bimodal signatures, making them easier to geochemically fingerprint.

Seed development, germination, and storage behaviour of Syzygium maire (Myrtaceae), a threatened endemic New Zealand tree

2020 ◽  
pp. 1-19
Author(s):  
Karin Van der Walt ◽  
Peter Kemp ◽  
Svetla Sofkova-Bobcheva ◽  
David J. Burritt ◽  
Jayanthi Nadarajan
Keyword(s):  
New Zealand ◽  
Seed Development ◽  
And Storage

Dissolved trace metals and their relationship to major elements in the Manuherikia River, a pristine subalpine catchment in central Otago, New Zealand

1991 ◽  
Vol 42 (4) ◽  
pp. 409 ◽  
Author(s):  
WW Ahlers ◽  
JP Kim ◽  
KA Hunter
Keyword(s):  
New Zealand ◽  
Trace Metals ◽  
Major Element ◽  
Major Ions ◽  
Major Elements ◽  
Lower Altitude ◽  
Weathering Processes ◽  
Global Standards ◽  
Dissolved Silicon ◽  
Dissolved Trace Metals

The spatial distributions of the dissolved trace metals Cu, Ni, Cd, Zn and Pb and of reactive Hg have been measured in parallel with the major elements Na, K, Mg and Ca and electrical conductivity in three sampling events in the Manuherikia River, New Zealand. The geographical span of the sampling sites ranged from a pristine subalpine upper catchment area through lower altitude sites that are increasingly affected by both natural weathering processes and moderate agricultural and domestic runoff. Major-element concentrations in the upper catchment were at or below the 1% frequency minimum of the spectrum of global river compositions, indicating a highly pristine system. Concen- trations increased steadily downstream to levels similar to world average river water. All trace metals exhibited the same spatial trends as the major ions. Typical upper-catchment concentrations were very low by global standards: Cu (150 ng L-1), Ni (100-150 ng L-1), Cd (8 ng L-I), Zn (150-200 ng L-1), Pb (20-30 ng L-1) and Hg (0.3 ng L-1). Oceanic residence times calculated from the data for Zn (80 000 years) and Cd (230 000 years) for which few reliable estimates have been made, are consistent with observed correlations between the oceanographic distributions of these elements and dissolved silicon or phosphate, respectively.

Fertility preservation in children newly diagnosed with cancer: Existing standards of practice in Australia and New Zealand

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 9047-9047
Author(s):  
J. A. Heath ◽  
C. J. Stern
Keyword(s):  
New Zealand ◽  
Fertility Preservation ◽  
Pediatric Oncology ◽  
North American ◽  
Ethical Issues ◽  
Ovarian Tissue ◽  
Newly Diagnosed ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
And Storage

9047 Background: Over the past two decades, rapid advances have occurred in both the successful treatment of childhood cancers and reproductive medicine. We sought to establish the current level of clinical practice for sperm, oocyte and gonadal tissue collection and storage in children newly diagnosed with cancer in Australia and New Zealand (ANZ). Methods: A cross-sectional survey of all pediatric oncology services in ANZ was performed. Comparisons to recently published North American practices and to current recommendations for best practice were also made. Results: Of the 13 centers invited to participate, 12 (92%) completed the survey. All centers had offered sperm conservation, but only ten (83%) had offered oocyte/ovarian tissue conservation. Available methods of gamete collection and storage were not consistent. Two centers were using GnRH agonists as fertility protection in post-pubertal females. Forty-two per cent had offered fertility conservation to males and females prior to completion of sexual development. All centers were more likely to offer sperm conservation than oocyte conservation for any given disease. The most common diseases for which conservation was offered were lymphomas and sarcomas. The anticipated cumulative dose at which centers elected to offer fertility preservation varied widely, both for the alkylator cyclophosphamide (1g/m2 to 10g/m2) and for abdominal/pelvic irradiation (any to 12 Gy) and spinal irradiation (any to 18Gy). Fertility counseling was offered in a variety of settings by 82% of centers. Despite 92% of centers agreeing that fertility preservation guidelines would be helpful, only two (17%) had any in place. Overall, there was greater uptake and consistency of utilization of fertility services in ANZ when compared with published North American data. Conclusions: There are inconsistencies regarding the indications for and methods of gamete conservation in pediatric oncology centers throughout ANZ. Unresolved medical, legal and ethical issues suggest the development of guidelines and a voluntary code of practice would be helpful. No significant financial relationships to disclose.

Starch metabolism during growth and storage of tubers of two New Zealand potato cultivars

1994 ◽  
Vol 22 (3) ◽  
pp. 295-304 ◽  
Author(s):  
Christine E. Lewis ◽  
Jane E. Lancaster ◽  
Peter Meredith ◽  
John R. L. Walker
Keyword(s):  
New Zealand ◽  
Potato Cultivars ◽  
Starch Metabolism ◽  
And Storage

UNDERSTANDING MAGMA RISE AND STORAGE USING MAJOR ELEMENTAL DIFFUSION IN OLIVINE; PUPUKE MAAR, AUCKLAND FIELD, NEW ZEALAND

2020 ◽  
Author(s):  
Madison Anae ◽  
◽  
Victoria Cassady ◽  
Ingrid Ukstins ◽  
Marco Brenna ◽  
...  
Keyword(s):  
New Zealand ◽  
Elemental Diffusion ◽  
And Storage

Polysaccharides from new zealand native plants: A review of their structure, properties, and potential applications

2020 ◽  
Author(s):  
Susan Carnachan ◽  
Tracey Bell ◽  
Simon Hinkley ◽  
Ian Sims
Keyword(s):  
New Zealand ◽  
Water Soluble ◽  
Composition And Structure ◽  
Structures And Properties ◽  
Wide Range ◽  
Potential Applications ◽  
Food Applications ◽  
Year 2000 ◽  
And Storage ◽  
Structure Properties

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Water-soluble, non-starch polysaccharides fromplants are used commercially in a wide range of food and non-food applications. The increasing range of applications for natural polysaccharides means that there is growing demand for plant-derived polysaccharides with different functionalities. The geographical isolation of New Zealand and its unique flora presents opportunities to discover new polysaccharides with novel properties for a range of applications. This review brings together data published since the year 2000 on the composition and structure of exudate gums, mucilages, and storage polysaccharides extracted from New Zealand endemic land plants. The structures and properties of these polysaccharides are compared with the structures of similar polysaccharides from other plants. The current commercial use of these polysaccharides is reviewed and their potential for further exploitation discussed.

Polysaccharides from new zealand native plants: A review of their structure, properties, and potential applications

2020 ◽  
Author(s):  
Susan Carnachan ◽  
Tracey Bell ◽  
Simon Hinkley ◽  
Ian Sims
Keyword(s):  
New Zealand ◽  
Water Soluble ◽  
Composition And Structure ◽  
Structures And Properties ◽  
Wide Range ◽  
Potential Applications ◽  
Food Applications ◽  
Year 2000 ◽  
And Storage ◽  
Structure Properties

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Water-soluble, non-starch polysaccharides fromplants are used commercially in a wide range of food and non-food applications. The increasing range of applications for natural polysaccharides means that there is growing demand for plant-derived polysaccharides with different functionalities. The geographical isolation of New Zealand and its unique flora presents opportunities to discover new polysaccharides with novel properties for a range of applications. This review brings together data published since the year 2000 on the composition and structure of exudate gums, mucilages, and storage polysaccharides extracted from New Zealand endemic land plants. The structures and properties of these polysaccharides are compared with the structures of similar polysaccharides from other plants. The current commercial use of these polysaccharides is reviewed and their potential for further exploitation discussed.

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