title: Cenozoic temperate and sub-tropical carbonate sedimentation on an oceanic volcano – Chatham Islands, New Zealand

authors: James, Noel P.

subjects: Bryozoans

abstract: The Chatham Islands, at the eastern end of the Chatham Rise in the South-west Pacific, are the emergent part of a Late Cretaceous to Cenozoic stratovolcano complex that is variably covered with limestones and fossiliferous tuffs. Most of these deposits accumulated in relatively shallow, high-energy, tide-influenced palaeoenvironments with deposition punctuated by periods of deeper-water pelagic accumulation. Carbonate components in these neritic deposits are biogenic and dominated by molluscs and bryozoans – a heterozoan assemblage. The widespread Middle to Late Eocene Matanginui Limestone contains local photozoan elements such as large benthonic foraminifera (especially Asterocyclina) and calcareous green algae, reflecting the general Palaeogene sub-tropical oceanographic setting. More localized Late Eocene to Oligocene deposits (Te One Limestone) as well as Pliocene carbonates (Onoua Limestone) are, however, wholly heterozoan and confirm a generally cooler-water oceanographic setting, similar to today. Early sea floor diagenesis is interpreted to have removed most aragonite components (infaunal bivalves and epifaunal gastropods). Lack of aragonite resulted in the absence of intergranular calcite cementation during subaerial exposure, such that most carbonates are friable or unlithified. Cementation is, however, present at nodular hardground–firmground caps to metre-scale cycles. Such cements are microcrystalline or micrometre-thick isopachous circumgranular rinds with insufficient definitive attributes to pinpoint their environment of formation. The overall palaeoenvironment of deposition is interpreted as mesotrophic, resulting in part from upwelling about the Chatham volcanic massif and in part from nutrient element delivery from the adjacent volcanic terrane and coeval volcanism. Biotic diversity in tuffs is two to three times that in limestones, supporting the notion of especially high nutrient availability during periods of volcanism. These mid-latitude deposits are strikingly different from their low-latitude, tropical, photozoan counterparts in the volcanic island–coral reef ecosystem. Ground water seepage and fluvial runoff attenuate coral growth and promote microbial carbonate precipitation in these warm-water settings. In contrast, nutrients from the same sources feed the system in the Chatham Islands cool-water setting, promoting active heterozoan carbonate sedimentation.

text: Cenozoic temperate and sub-tropical carbonate sedimentation on an oceanic volcano – Chatham Islands, New Zealand The Chatham Islands, at the eastern end of the Chatham Rise in the South-west Pacific, are the emergent part of a Late Cretaceous to Cenozoic stratovolcano complex that is variably covered with limestones and fossiliferous tuffs. Most of these deposits accumulated in relatively shallow, high-energy, tide-influenced palaeoenvironments with deposition punctuated by periods of deeper-water pelagic accumulation. Carbonate components in these neritic deposits are biogenic and dominated by molluscs and bryozoans – a heterozoan assemblage. The widespread Middle to Late Eocene Matanginui Limestone contains local photozoan elements such as large benthonic foraminifera (especially Asterocyclina) and calcareous green algae, reflecting the general Palaeogene sub-tropical oceanographic setting. More localized Late Eocene to Oligocene deposits (Te One Limestone) as well as Pliocene carbonates (Onoua Limestone) are, however, wholly heterozoan and confirm a generally cooler-water oceanographic setting, similar to today. Early sea floor diagenesis is interpreted to have removed most aragonite components (infaunal bivalves and epifaunal gastropods). Lack of aragonite resulted in the absence of intergranular calcite cementation during subaerial exposure, such that most carbonates are friable or unlithified. Cementation is, however, present at nodular hardground–firmground caps to metre-scale cycles. Such cements are microcrystalline or micrometre-thick isopachous circumgranular rinds with insufficient definitive attributes to pinpoint their environment of formation. The overall palaeoenvironment of deposition is interpreted as mesotrophic, resulting in part from upwelling about the Chatham volcanic massif and in part from nutrient element delivery from the adjacent volcanic terrane and coeval volcanism. Biotic diversity in tuffs is two to three times that in limestones, supporting the notion of especially high nutrient availability during periods of volcanism. These mid-latitude deposits are strikingly different from their low-latitude, tropical, photozoan counterparts in the volcanic island–coral reef ecosystem. Ground water seepage and fluvial runoff attenuate coral growth and promote microbial carbonate precipitation in these warm-water settings. In contrast, nutrients from the same sources feed the system in the Chatham Islands cool-water setting, promoting active heterozoan carbonate sedimentation.

year: 2010

title: Intramolecular OH∙∙∙π interactions in alkenols and alkynols

authors: Miller, Benjamin J.

subjects: chemistry

abstract: The vibrational overtone spectra of propargyl alcohol (prop-2-yn-1-ol, PA), allyl alcohol (prop-2-en-1-ol, AA), propargyl carbinol (but-3-yn-1-ol, PC) and allyl carbinol (but-3-en-1-ol, AC) were recorded with intracavity laser photoacoustic spectroscopy (ICL-PAS) in the ΔvOH = 3, 4 and 5 regions for propargyl alcohol and allyl alcohol and in the ΔvOH = 4 and 5 regions for propargyl carbinol and allyl carbinol. Local mode anharmonic oscillator calculations were performed with explicitly correlated coupled cluster methods to guide spectral assignment. Atoms in molecules (AIM) and non-covalent interactions (NCI) calculations were carried out to analyze the interactions between the OH-group and the π-electrons of the carbon–carbon multiple bonds. We ascertain the effect of the carbon chain length and saturation on the conformation and spectroscopy of the four alcohols in relation to intramolecular hydrogen bonding interactions.

text: Intramolecular OH∙∙∙π interactions in alkenols and alkynols The vibrational overtone spectra of propargyl alcohol (prop-2-yn-1-ol, PA), allyl alcohol (prop-2-en-1-ol, AA), propargyl carbinol (but-3-yn-1-ol, PC) and allyl carbinol (but-3-en-1-ol, AC) were recorded with intracavity laser photoacoustic spectroscopy (ICL-PAS) in the ΔvOH = 3, 4 and 5 regions for propargyl alcohol and allyl alcohol and in the ΔvOH = 4 and 5 regions for propargyl carbinol and allyl carbinol. Local mode anharmonic oscillator calculations were performed with explicitly correlated coupled cluster methods to guide spectral assignment. Atoms in molecules (AIM) and non-covalent interactions (NCI) calculations were carried out to analyze the interactions between the OH-group and the π-electrons of the carbon–carbon multiple bonds. We ascertain the effect of the carbon chain length and saturation on the conformation and spectroscopy of the four alcohols in relation to intramolecular hydrogen bonding interactions.

year: 2011

title: Māori loanwords: a corpus of New Zealand English tweets

authors: Trye, David

abstract: Māori loanwords are widely used in New Zealand English for various social functions by New Zealanders within and outside of the Māori community. Motivated by the lack of linguistic resources for studying how Māori loanwords are used in social media, we present a new corpus of New Zealand English tweets. We collected tweets containing selected Māori words that are likely to be known by New Zealanders who do not speak Māori. Since over 30% of these words turned out to be irrelevant (e.g., mana is a popular gaming term, Moana is a character from a Disney movie), we manually annotated a sample of our tweets into relevant and irrelevant categories. This data was used to train machine learning models to automatically filter out irrelevant tweets.

text: Māori loanwords: a corpus of New Zealand English tweets Māori loanwords are widely used in New Zealand English for various social functions by New Zealanders within and outside of the Māori community. Motivated by the lack of linguistic resources for studying how Māori loanwords are used in social media, we present a new corpus of New Zealand English tweets. We collected tweets containing selected Māori words that are likely to be known by New Zealanders who do not speak Māori. Since over 30% of these words turned out to be irrelevant (e.g., mana is a popular gaming term, Moana is a character from a Disney movie), we manually annotated a sample of our tweets into relevant and irrelevant categories. This data was used to train machine learning models to automatically filter out irrelevant tweets.

year: 2019