scholarly journals Late Cenozoic Erosion in New Zealand

2021 ◽  
Author(s):  
◽  
John Edward Adams
Keyword(s):  
Steady State ◽  
New Zealand ◽  
Normal Load ◽  
Suspended Load ◽  
Southern Alps ◽  
Tectonic Uplift ◽  
Minor Importance ◽  
Oblique Collision ◽  
The Individual ◽  
Almost All

<p>Uplift and erosion are roughly equal in the Southern Alps of New Zealand and the following rates have been determined: tectonic uplift 620 +/- 20 Mt y^-1, river load 700 +/- 200 Mt y^-1, offshore deposition 580 +/- 110 Mt y^-1. The tectonic uplift is the result of oblique collision between the Indian and Pacific plates, with the edge of the Pacific plate being upturned and uplifted as the Southern Alps, crustal narrowing of 22 mm y^-1 being converted to uplift along a curved fault plane. Almost all rock eroded from the Southern Alps is carried as suspended load by rivers. River bedload is of minor importance, and its abrasion adds to the suspended load. The estimated suspended load amounts to 265 Mt y^-1, but with a single exception only normal load have been sampled, and the additional abnormal load from earthquake-caused landslips is estimated to double the normal load. The river load estimate is confirmed in part by spot checks from sediment accumulated in onshore traps. A model proposed for the growth of the Southern Alps from a peneplain shows that the range attained steady state about 1.5 My after uplift started. With uplift initial non steady state, flat topped mountains like those that remain in Otago, become steady state spiky mountains. The range as a whole is in steady state, though the individual mountains change. The offshore deposition rates agree with the river load and tectonic uplift estimates and thus provide substantial confirmation for the steady state model.</p>

scholarly journals Late Cenozoic Erosion in New Zealand

2021 ◽  
Author(s):  
◽  
John Edward Adams
Keyword(s):  
Steady State ◽  
New Zealand ◽  
Normal Load ◽  
Suspended Load ◽  
Southern Alps ◽  
Tectonic Uplift ◽  
Minor Importance ◽  
Oblique Collision ◽  
The Individual ◽  
Almost All

<p>Uplift and erosion are roughly equal in the Southern Alps of New Zealand and the following rates have been determined: tectonic uplift 620 +/- 20 Mt y^-1, river load 700 +/- 200 Mt y^-1, offshore deposition 580 +/- 110 Mt y^-1. The tectonic uplift is the result of oblique collision between the Indian and Pacific plates, with the edge of the Pacific plate being upturned and uplifted as the Southern Alps, crustal narrowing of 22 mm y^-1 being converted to uplift along a curved fault plane. Almost all rock eroded from the Southern Alps is carried as suspended load by rivers. River bedload is of minor importance, and its abrasion adds to the suspended load. The estimated suspended load amounts to 265 Mt y^-1, but with a single exception only normal load have been sampled, and the additional abnormal load from earthquake-caused landslips is estimated to double the normal load. The river load estimate is confirmed in part by spot checks from sediment accumulated in onshore traps. A model proposed for the growth of the Southern Alps from a peneplain shows that the range attained steady state about 1.5 My after uplift started. With uplift initial non steady state, flat topped mountains like those that remain in Otago, become steady state spiky mountains. The range as a whole is in steady state, though the individual mountains change. The offshore deposition rates agree with the river load and tectonic uplift estimates and thus provide substantial confirmation for the steady state model.</p>

Potential of detailed geomorphological mapping for the study of Holocene glacier chronologies: Mueller Glacier, Southern Alps/New Zealand

2020 ◽  
Author(s):  
Stefan Winkler
Keyword(s):  
New Zealand ◽  
High Resolution ◽  
Southern Alps ◽  
Genetic Origin ◽  
Geomorphological Mapping ◽  
Glacier Foreland ◽  
Geomorphological Map ◽  
Study Sites ◽  
The Individual ◽  
Almost All

&lt;p&gt;The investigation of Holocene glacier chronologies has been recognised as a key element of research on mountain glaciations in the light of current global change. They can be utilised as high-resolution palaeoclimatic archives for the immediate and more distant geological past. During the past few decades considerable progress has been achieved, in particular due to substantial improvements of the ability to accurately date glacial landforms such as terminal moraines essential for reconstructing past glacier margins and subsequent analysis in the context of glacier advance/retreat periods. The Southern Alps of New Zealand are among the few suitable study sites for the investigation of Holocene glacier chronologies in the mid-latitudinal Southern Hemisphere that consequently have drawn attention.&lt;/p&gt;&lt;p&gt;Since early studies of Holocene glacier chronologies in the mid-20th century, mapping of the investigated glacier forelands has been an integrated part of almost all scientific approaches regardless of the individual dating methods that may have been applied. These mapping attempts serve the identification and positioning of certain glacial or glaciofluvial landforms subsequently allowing the reconstruction of former glacier margins. They frequently also provide information about the location of sample sites for the various dating techniques applied. If detailed geomorphological mapping schemes are in use, such maps additionally support the interpretation of any chronological data by identifying the genetic origin of any landform investigated, thus enabling to link the latter to different dynamic stages of the glacier. Additionally, such maps may highlight related uncertainties such as postdepositional disturbance or potentially unclear morphodynamic relationships to the glacier's behaviour.&lt;/p&gt;&lt;p&gt;Reviewing recent publications it seems, however, that some appraisal of such detailed geomorphological mapping is often traded-off against the impressive progress with up-to-date dating techniques and high-resolution digital elevation models or satellite/aerial imagery. Unfortunately, the latter do neither qualify as geomorphological maps &lt;em&gt;per se&lt;/em&gt; or fully serve the abovementioned purposes. The widespread applied common GIS software has, furthermore, limitations with respect to its graphic capabilities and unintentionally entails negligence of established and well-suited signatures or mapping schemes.&lt;/p&gt;&lt;p&gt;A detailed geomorphological map of the glacier foreland of Mueller Glacier, Southern Alps/New Zealand is presented as a case study. It follows an established geomorphological mapping scheme (&quot;GMK 25&quot;) that has been adequately modified to fit both purpose and selected scale. Despite several glacier chronological studies have been conducted on this glacier foreland and the site is considered as a regional key site for related research, this map constitutes the first of its kind. The detailed geomorphological map is utilised to assess discrepancies among existing chronologies by reviewing the morphometric properties and genetic origin of those landforms that have been dated. It reveals that potential postdepositional modification of some landforms investigated had not been appropriately considered with certain previous studies. As a result, the evidence of few glacier advances needs to be classified as weak.&amp;#160;&amp;#160;&lt;/p&gt;&lt;p&gt;Summarising, detailed geomorphological mapping is still essential for the study of Holocene glacier chronologies and should not lose its prominent position or even disappear.&lt;/p&gt;

scholarly journals Review of the New Zealand Theileria orientalis Ikeda Type Epidemic and Epidemiological Research since 2012

Pathogens ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1346
Author(s):  
Kevin Lawrence ◽  
Kristene Gedye ◽  
Andrew McFadden ◽  
David Pulford ◽  
Allen Heath ◽  
...  
Keyword(s):  
New Zealand ◽  
New Disease ◽  
Epidemiological Investigation ◽  
Epidemiological Research ◽  
Theileria Orientalis ◽  
Production Animals ◽  
The Individual ◽  
Cattle Systems ◽  
Almost All ◽  
Type Infection

This article sets out to document and summarise the New Zealand epidemic and the epidemiological research conducted on the epizootic of bovine anaemia associated with Theileria orientalis Ikeda-type infection, which began in New Zealand in August 2012. As New Zealand has no other pathogenic tick-borne cattle haemoparasites, the effects of the T. orientalis Ikeda-type infection observed in affected herds and individual animals were not confounded by other concurrent haemoparasite infections, as was possibly the case in other countries. This has resulted in an unbiased perspective of a new disease. In addition, as both New Zealand’s beef and dairy cattle systems are seasonally based, this has led to a different epidemiological presentation than that reported by almost all other affected countries. Having verified the establishment of a new disease and identified the associated pathogen, the remaining key requirements of an epidemiological investigation, for a disease affecting production animals, are to describe how the disease spreads, describe the likely impacts of that disease at the individual and herd level and explore methods of disease control or mitigation.

Greenhouses, hot water bottles, cycles and the future of New Zealand climate

2009 ◽  
pp. 61-67
Author(s):  
W.P. De Lange
Keyword(s):  
New Zealand ◽  
Thermal Energy ◽  
Infrared Radiation ◽  
Little Ice Age ◽  
Hot Water ◽  
Ice Age ◽  
The Sun ◽  
Weather Patterns ◽  
Time Periods ◽  
Almost All

The Greenhouse Effect acts to slow the escape of infrared radiation to space, and hence warms the atmosphere. The oceans derive almost all of their thermal energy from the sun, and none from infrared radiation in the atmosphere. The thermal energy stored by the oceans is transported globally and released after a range of different time periods. The release of thermal energy from the oceans modifies the behaviour of atmospheric circulation, and hence varies climate. Based on ocean behaviour, New Zealand can expect weather patterns similar to those from 1890-1922 and another Little Ice Age may develop this century.

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