Multiple Sources for Sea-Rafted Loisels Pumice, New Zealand

1998 ◽  
Vol 49 (3) ◽  
pp. 271-279 ◽  
Author(s):  
Phil Shane ◽  
Paul Froggatt ◽  
Ian Smith ◽  
Murray Gregory
Keyword(s):  
New Zealand ◽  
Late Holocene ◽  
Ocean Currents ◽  
Multiple Sources ◽  
Tasman Sea ◽  
First Arrival ◽  
Mineral Compositions ◽  
Coastal Deposits ◽  
Low K ◽  
Westward Drift

Sea-rafted Loisels Pumice is one of the few stratigraphic markers used to correlate late Holocene coastal deposits in New Zealand. Along with underlying sea-rafted products of the local Taupo eruption of ca. 1800 yr B.P., these events have been used to bracket the first arrival of humans at New Zealand. Loisels Pumice is dacitic to rhyolitic (SiO2 63–78 wt%) in composition, but individual clasts are homogeneous (SiO2 range ± 1 wt%). Characteristics include very low K2O (0.5–1.75 wt%) and Rb (<25 ppm) and a mineralogy dominated by calcic and mafic xenocrysts. Similar features are shared by pumices of the Tonga–Kermadec arc, suggesting a common tholeiitic oceanic source. Interclast diversity of Loisels Pumice suggests that it is the product of several eruptive events from different volcanoes. The differences in glass and mineral compositions found at various sites can be explained if the deposits are from different events. A multisource origin can also partially explain the discrepancy in reported 14C ages (ca. 1500–600 yr B.P.) from different localities. Therefore, the value of Loisels Pumice as a stratigraphic marker is questionable, and it does not constrain the arrival of humans. The predominant westward drift of historic Tonga–Kermadec arc pumices and prevailing ocean currents suggest a long anticlockwise semicircular transport route into the Tasman Sea before sea-rafted pumice arrival in New Zealand. The diversity of the pumices indicates that silicic eruptions frequently occur from the predominantly basic oceanic volcanoes.

Enterococci in the New Zealand environment: implications for water quality monitoring

1997 ◽  
Vol 35 (11-12) ◽  
pp. 325-331 ◽  
Author(s):  
S. A. Anderson ◽  
S. J. Turner ◽  
G. D. Lewis
Keyword(s):  
Water Quality ◽  
New Zealand ◽  
Water Quality Monitoring ◽  
Epidemiological Studies ◽  
High Ratio ◽  
Quality Data ◽  
Considerable Proportion ◽  
Multiple Sources ◽  
Water Quality Data ◽  
Bathing Water Quality

Faecal enterococci ecology outside the host is of great relevance when using these organisms as indicators of water quality. As a complement to New Zealand epidemiological studies of bathing water quality and health risk, a study of the environmental occurrence of these organisms has been undertaken. Specific concerns over the use of enterococci derive from the unique situation in New Zealand which has few chlorinated sewage effluents, a high ratio of grazing animals to humans, and significant inputs of animal processing effluents into the environment. Human and animal faecal wastes are the main sources, with 106–107cfu/100ml found in human sewage. Analysis of domestic and feral animal faeces found enterococci in the range of 101–106cfu/g with considerable variation between species. The latter observations support the notion that a considerable proportion of the load in urban/rural catchments and waterways (typically 102–103 enterococci cfu/100ml) is derived from non-human sources. Previous studies of enterococci quiescence in marine/fresh waters indicate that they enter a non-growth phase, exposure to sunlight markedly reducing culturability on selective and non-selective media. Enterococci were also found to survive/multiply within specific non-faecal environments. Enterococci on degrading drift seaweed at recreational beaches exceeded seawater levels by 2–4 orders of magnitude, suggesting that expansion had occurred in this permissive environment with resultant potential to contaminate adjacent sand and water. These studies suggest that multiple sources, environmental persistence, and environmental expansion of enterococci within selected niches add considerable complexity to the interpretation of water quality data.

MS prevalence in New Zealand, an ethnically and latitudinally diverse country

2010 ◽  
Vol 16 (12) ◽  
pp. 1422-1431 ◽  
Author(s):  
Bruce V Taylor ◽  
John F Pearson ◽  
Glynnis Clarke ◽  
Deborah F Mason ◽  
David A Abernethy ◽  
...  
Keyword(s):  
New Zealand ◽  
Environmental Factors ◽  
Latitudinal Gradient ◽  
Population Level ◽  
Cross Sectional Study ◽  
European Population ◽  
Multiple Sources ◽  
Cross Sectional ◽  
The North ◽  
Mcdonald Criteria

Background: The prevalence of multiple sclerosis (MS) is not uniform, with a latitudinal gradient of prevalence present in most studies. Understanding the drivers of this gradient may allow a better understanding of the environmental factors involved in MS pathogenesis. Method: The New Zealand national MS prevalence study (NZMSPS) is a cross-sectional study of people with definite MS (DMS) (McDonald criteria 2005) resident in New Zealand on census night, 7 March 2006, utilizing multiple sources of notification. Capture—recapture analysis (CRA) was used to estimate missing cases. Results: Of 2917 people with DMS identified, the crude prevalence was 72.4 per 100,000 population, and 73.1 per 100,000 when age-standardized to the European population. CRA estimated that 96.7% of cases were identified. A latitudinal gradient was seen with MS prevalence increasing three-fold from the North (35°S) to the South (48°S). The gradient was non-uniform; females with relapsing—remitting/secondary-progressive (RRMS/SPMS) disease have a gradient 11 times greater than males with primary-progressive MS ( p < 1 × 10-7). DMS was significantly less common among those of Māori ethnicity. Conclusions: This study confirms the presence of a robust latitudinal gradient of MS prevalence in New Zealand. This gradient is largely driven by European females with the RRMS/SPMS phenotype. These results indicate that the environmental factors that underlie the latitudinal gradient act differentially by gender, ethnicity and MS phenotype. A better understanding of these factors may allow more targeted MS therapies aimed at modifiable environmental triggers at the population level.

ATOC and Other Acoustic Thermometry Observations In New Zealand

1999 ◽  
Vol 33 (1) ◽  
pp. 55-60
Author(s):  
C.T. Tindle ◽  
G.E.J.
Keyword(s):  
New Zealand ◽  
Ocean Bottom ◽  
Underwater Sound ◽  
Floating Platform ◽  
Ocean Climate ◽  
Acoustic Thermometry ◽  
Tasman Sea ◽  
Heard Island ◽  
Large Fluctuations ◽  
Feasibility Test

A summary of participation of the New Zealand group in the ATOC (Acoustic Thermometry of Ocean Climate) program over a five year period is presented. Transmissions from Heard Island were observed in the Tasman Sea during the Heard Island Feasibility Test in 1991. The California-New Zealand underwater sound path was verified with explosive sources in 1992. Single hydrophone observations were made of transmissions to New Zealand from California from an electrically driven source first suspended beneath a floating platform in 1994 and later placed on the ocean bottom at Pioneer Seamount in 1995. Results from these experiments show that acoustic propagation to ranges of order 10 Mm appears to be characterised by large fluctuations occurring with a time scale of a few minutes.

1995 Ruapehu lahars in relation to the late Holocene lahars of Whangaehu River, New Zealand

1997 ◽  
Vol 40 (4) ◽  
pp. 507-520 ◽  
Author(s):  
Shane J. Cronin ◽  
K. A. Hodgson ◽  
V. E. Neall ◽  
A. S. Palmer ◽  
J.A. Lecointre
Keyword(s):  
New Zealand ◽  
Late Holocene

scholarly journals Soldiers & Colonists: Imperial Soldiers as Settlers in Nineteenth-Century New Zealand

2021 ◽  
Author(s):  
◽  
John McLellan
Keyword(s):  
Nineteenth Century ◽  
New Zealand ◽  
British Empire ◽  
Settler Colonialism ◽  
Land Grants ◽  
Family Networks ◽  
History Of ◽  
First Arrival ◽  
Government Records ◽  
Decision To Stay

<p>The approximately 18,000 imperial troops who arrived in New Zealand with the British regiments between 1840 and 1870 as garrison and combat troops, did not do so by choice. However, for the more than 3,600 non-commissioned officers and rank and file soldiers who subsequently discharged from the army in New Zealand, and the unknown but significant number of officers who retired in the colony, it was their decision to stay and build civilian lives as soldier settlers in the colony. This thesis investigates three key themes in the histories of soldiers who became settlers: land, familial relationships, and livelihood. In doing so, the study develops an important area of settler colonialism in New Zealand history. Discussion covers the period from the first arrival of soldiers in the 1840s through to the early twentieth century – incorporating the span of the soldier settlers’ lifetimes. The study focuses on selected aspects of the history of nineteenth-century war and settlement.  Land is examined through analysis of government statutes and reports, reminiscences, letters, and newspapers, the thesis showing how and why soldier settlers were assisted on to confiscated and alienated Māori land under the Waste Lands and New Zealand Settlement Acts. Attention is also paid to documenting the soldier settlers’ experiences of this process and its problems. Further, it discusses some of the New Zealand settlements in which military land grants were concentrated. It also situates such military settlement practices in the context of the wider British Empire.  The place of women, children, and the regimental family in the soldier settlers’ New Zealand lives is also considered. This history is explored through journals, reminiscences, biography and newspapers, and contextualised via imperial and military histories. How and where men from the emphatically male sphere of the British Army met and married women during service in New Zealand is examined, as are the contexts in which they lived their married lives. Also discussed are the contrasting military and colonial policies towards women and marriage, and how these were experienced by soldier settlers and their families.  Lastly, the livelihood of soldier settlers is explored – the thesis investigating what sort of civilian lives soldier settlers experienced and how they made a living for themselves and their families. Utilising newspapers, reminiscences, biography, and government records the diversity of work army veterans undertook in the colony is uncovered. Notable trends include continued military-style roles and community leadership. The failed farming enterprise is also emphasised. Going further, it offers analysis of the later years of life and the different experiences of soldier settlers in their twilight years, particularly for those with and without family networks in the colony. The thesis challenges the separation between ‘war’ and ‘settlement’ by focusing on a group whose history spanned both sides of the nineteenth-century world of colony and empire.</p>

scholarly journals Late Holocene intensification of the westerly winds at the subantarctic Auckland Islands (51° S), New Zealand

2017 ◽  
Author(s):  
Imogen M. Browne ◽  
Christopher M. Moy ◽  
Christina R. Riesselman ◽  
Helen L. Neil ◽  
Lorelei G. Curtin ◽  
...  
Keyword(s):  
New Zealand ◽  
Late Holocene ◽  
Drainage Basin ◽  
Southern Oscillation ◽  
Southern Annular Mode ◽  
Ice Age ◽  
The Pacific ◽  
Westerly Winds ◽  
Latitudinal Position ◽  
Paleoclimate Records

Abstract. The Southern Hemisphere westerly winds (SHWW) play a major role in controlling wind-driven upwelling of Circumpolar Deep Water (CDW) and outgassing of CO2 in the Southern Ocean on interannual to glacial-interglacial timescales. Despite their significance in the global carbon cycle, our understanding of millennial-scale changes in the strength and latitudinal position of the westerlies during the Holocene (especially since 5000 yr BP) is limited by a scarcity of paleoclimate records from comparable latitudes. Here, we reconstruct middle to late Holocene variability in the SHWW using a fjord sediment core collected from the subantarctic Auckland Islands (51° S, 166° E), located in the modern centre of the westerly wind belt. Drainage basin response to variability in the strength of the SHWW at this latitude is reconstructed from downcore variations in magnetic susceptibility (MS) and bulk organic δ13C and atomic C/N, which monitor influxes of lithogenous and terrestrial vs marine organic matter, respectively. The hydrographic response to SHWW variability is reconstructed using benthic foraminifer δ18O and δ13C, both of which are influenced by the isotopic composition of shelf water masses entering the fjord. Using these data, we provide marine and terrestrial-based evidence for increased wind strength from ~ 1600–900 yr BP at subantarctic latitudes that is broadly consistent with previous studies of vegetation response to climate at the Auckland Islands. Comparison with a SHWW reconstruction using similar proxies from Fiordland suggests a northward migration of the SHWW over New Zealand at the beginning of the Little Ice Age (LIA). Comparison with paleoclimate and paleoceanographic records from southern South America and the western Antarctic Peninsula indicates a late Holocene strengthening of the SHWW after ~ 1600 yr BP that appears to be broadly symmetrical across the Pacific basin, although our reconstruction suggests that this symmetry breaks down during the LIA. Contemporaneous increases in SHWW at localities either side of the Pacific in the late Holocene are likely controlled atmospheric teleconnections between the low and high latitudes and by variability in the Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO).

scholarly journals Detection of Large Holocene Earthquakes in the Sedimentary Record of Wellington, New Zealand, Using Diatom Analysis

2021 ◽  
Author(s):  
◽  
Ursula Alyson Cochran
Keyword(s):  
New Zealand ◽  
Late Holocene ◽  
Weighted Averaging ◽  
Diatom Analysis ◽  
Sedimentary Record ◽  
Sedimentary Sequences ◽  
Quantitative Estimates ◽  
Modern Analogue ◽  
Environmental Transitions ◽  
Large Earthquakes

<p>New Zealand is situated on the boundary between the Pacific and Australian tectonic plates. The Wellington region lies near the southern end of the Hikurangi subduction zone and within a zone of major, active strike-slip faults. Wellington's paleoseismic and historic records indicate that large surface rupture earthquakes have occurred on these faults in the past. Development of a complete record of past large earthquakes is a high priority for the region because of the risk posed by occurrence of large earthquakes in the future. The existing paleoseismic record has been derived predominantly from studies of fault trench stratigraphy, raised beach ridges and offset river terraces. The sedimentary record of lakes and coastal waterbodies is a source of information that has not been used specifically for paleoseismic purposes in the region. Therefore investigation of Wellington's sedimentary record is used in this thesis to make a contribution to the paleoseismic record. Holocene sedimentary sequences are studied from three small, low elevation, coastal waterbodies: Taupo Swamp, Okupe Lagoon and Lake Kohangapiripiri. Sequences of between 200 and 650 cm depth were collected using a hand-operated coring device. Sedimentology and diatom microfossil content were analysed and interpreted to enable reconstruction of paleoenvironment at each site. Radiocarbon dating was used to provide chronologies for the sequences that are aged between 5000 and 7500 calibrated years before present (cal. years BP). Diatom analysis is the main tool used to reconstruct paleoenvironment and detect evidence for occurrence of past large earthquakes. To aid reconstruction of sedimentary sequences used in this project, as well as coastal sequences in New Zealand in general, a coastal diatom calibration set was constructed using 50 sites around New Zealand. Modern diatom distribution and abundance, and associated environmental variables are analysed using ordination and weighted averaging techniques. Detrended correspondence analysis arranges species according to salinity preferences and divides sites clearly into waterbody types along a coastal gradient. This analysis enables reconstruction of waterbody type from fossil samples by passive placement onto ordination diagrams. Weighted averaging regression of calibration set samples results in a high correlation (r2jack=0.84) between observed and diatom inferred salinity, and enables salinity preferences and tolerances to be derived for 100 species. This confirms for the first time that species' preferences derived in the Northern Hemisphere are generally applicable to diatoms living in the coastal zone of New Zealand. Weighted averaging calibration and the modern analogue technique are used to generate quantitative estimates of paleosalinity for fossil samples. Paleoenvironmental reconstructions of Taupo Swamp, Okupe Lagoon and Lake Kohangapiripiri indicate that each waterbody has been isolated from the sea during the late Holocene. Isolation has been achieved through interplay of sediment accumulation causing growth of barrier beaches, and coseismic uplift. Ten distinct transitions between different paleoenvironments are recognised from the three sequences. These transitions involve changes in relative sea level or water table level often in association with catchment disturbance or marine influx events. All transitions occur suddenly and are laterally extensive and synchronous within each waterbody. Quantitative estimates of paleosalinity and waterbody type are used to differentiate between large and small magnitude changes in paleoenvironment. Five transitions involve large amounts of paleoenvironmental change and provide evidence for earthquakes occurring at approximately 5200, approximately 3200, and approximately 2300 cal. years BP. Five other transitions are consistent with the effects of large earthquakes occurring at approximately 6800, 2200, approximately 1000, approximately 500 cal. years BP and 1855 AD but do not provide independent evidence of the events. Environmental transitions at Lake Kohangapiripiri clarify the timing of rupture of the Wairarapa Fault by bracketing incompatible age estimates derived from two different sites on the fault. The oldest environmental transitions recognised at Taupo Swamp and Okupe Lagoon both occur at approximately 3200 cal. years BP indicating that western Wellington was uplifted at this time. Environmental transitions are recorded at all three study sites at approximately 2300 cal. years BP indicating that the entire western and central Wellington region experienced coseismic uplift at this time. Because of the distance between sites this apparent synchroneity implies that several faults in the region ruptured at a similar time. Investigation of sedimentary sequences contributes to the existing paleoseismic record by providing additional estimates of timing for past large earthquakes, enabling estimation of the areal extent of the effects of past earthquakes, and by highlighting periods of fault rupture activity in the late Holocene.</p>

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