scholarly journals Cretaceous and Cenozoic Basin Evolution Based on Decompacted Sediment Thickness from Petroleum Wells around New Zealand

2021 ◽  
Author(s):  
◽  
Louise Jane Christie
Keyword(s):  
New Zealand ◽  
Sedimentary Basins ◽  
Mantle Flow ◽  
Basin Evolution ◽  
Alpine Fault ◽  
Basin Subsidence ◽  
Tasman Sea ◽  
Petroleum Wells ◽  
Almost All ◽  
Conjugate Margins

<p>Decompacted sedimentary data from 33 New Zealand exploration wells is used to investigate basin evolution and tectonics from around New Zealand. This analysis is directed to both a comparison of basin behaviour and a search for common subsidence signatures. Common to almost all New Zealand basin subsidence curves is a sedimentary signature associated with rifting of the Gondwana super-continent (80-65 Ma). In the Great South Basin a second rifting event is inferred at 51 [plus or minus] 2 Ma, illustrated by a rapid increase in subsidence rates (with a maximum rate of 190 m.Myr-1 at Pakaha-1). Coinciding with the cessation of Tasman Sea rifting ([approximately] 53 Ma), and with the onset of rifting in the Emerald Basin ([approximately] 50 Ma), it is assumed that the event is related to the tectonic plate reorganization. An increase in sedimentation is noted at [approximately] 20 Ma in most South Island wells. Convergence on the Alpine Fault, leading to increased erosion is cited as a mechanism for this period of basin growth, consistent with the Cande and Stock (2004) model of plate motions. A second increase in sedimentation occurs at [approximately] 6 Ma in almost all wells around New Zealand. Climate-driven erosion resulting in isostatic uplift is thought to contribute to this event. Hiatuses in the sedimentary record for the Canterbury, Great South and Western Southland Basins during the late Oligocene are interpreted as the Marshall Paraconformity. It appears that the break in sedimentation located within a regional transgressional mega-sequence was caused by mid Oligocene glacio-eustatic fall and related oceanic current processes. Loading by the Northland Allochthon, in conjunction with paleobathymetry and subsidence data, is used to demonstrate the mechanical properties of the lithosphere. A lithospheric rigidity of 1.5 x [10 to the power of 22] Nm is estimated, with an elastic thickness of 12 km. Considerably lower than elastic thickness values previously calculated for the Plio-Pleistocene loading of the Taranaki Platform. It is noted that the Northland value represents a younger, hotter crust at the time of load emplacment. With the exception of the central Taranaki and Great South Basins, stretching factors ([Beta]) for the sedimentary basins surrounding New Zealand are below 2. This suggests crustal thickness prior to rifting was between 35 and 50 km, consistent with data from conjugate margins of Australia and Antarctica. An increase in water depth in the Taranaki Basin at 25 [plus or minus] 3 Ma is confirmed by this study. This coincides with a similar signature on the West Coast of the South Island at 26 [plus or minus] 2 Ma. It is suggested that a mantle flow caused by the initiation of the subduction zone at [approximately] 25 Ma extends over a broader region (>750 km) than previously thought.</p>

scholarly journals Cretaceous and Cenozoic Basin Evolution Based on Decompacted Sediment Thickness from Petroleum Wells around New Zealand

2021 ◽  
Author(s):  
◽  
Louise Jane Christie
Keyword(s):  
New Zealand ◽  
Sedimentary Basins ◽  
Mantle Flow ◽  
Basin Evolution ◽  
Alpine Fault ◽  
Basin Subsidence ◽  
Tasman Sea ◽  
Petroleum Wells ◽  
Almost All ◽  
Conjugate Margins

<p>Decompacted sedimentary data from 33 New Zealand exploration wells is used to investigate basin evolution and tectonics from around New Zealand. This analysis is directed to both a comparison of basin behaviour and a search for common subsidence signatures. Common to almost all New Zealand basin subsidence curves is a sedimentary signature associated with rifting of the Gondwana super-continent (80-65 Ma). In the Great South Basin a second rifting event is inferred at 51 [plus or minus] 2 Ma, illustrated by a rapid increase in subsidence rates (with a maximum rate of 190 m.Myr-1 at Pakaha-1). Coinciding with the cessation of Tasman Sea rifting ([approximately] 53 Ma), and with the onset of rifting in the Emerald Basin ([approximately] 50 Ma), it is assumed that the event is related to the tectonic plate reorganization. An increase in sedimentation is noted at [approximately] 20 Ma in most South Island wells. Convergence on the Alpine Fault, leading to increased erosion is cited as a mechanism for this period of basin growth, consistent with the Cande and Stock (2004) model of plate motions. A second increase in sedimentation occurs at [approximately] 6 Ma in almost all wells around New Zealand. Climate-driven erosion resulting in isostatic uplift is thought to contribute to this event. Hiatuses in the sedimentary record for the Canterbury, Great South and Western Southland Basins during the late Oligocene are interpreted as the Marshall Paraconformity. It appears that the break in sedimentation located within a regional transgressional mega-sequence was caused by mid Oligocene glacio-eustatic fall and related oceanic current processes. Loading by the Northland Allochthon, in conjunction with paleobathymetry and subsidence data, is used to demonstrate the mechanical properties of the lithosphere. A lithospheric rigidity of 1.5 x [10 to the power of 22] Nm is estimated, with an elastic thickness of 12 km. Considerably lower than elastic thickness values previously calculated for the Plio-Pleistocene loading of the Taranaki Platform. It is noted that the Northland value represents a younger, hotter crust at the time of load emplacment. With the exception of the central Taranaki and Great South Basins, stretching factors ([Beta]) for the sedimentary basins surrounding New Zealand are below 2. This suggests crustal thickness prior to rifting was between 35 and 50 km, consistent with data from conjugate margins of Australia and Antarctica. An increase in water depth in the Taranaki Basin at 25 [plus or minus] 3 Ma is confirmed by this study. This coincides with a similar signature on the West Coast of the South Island at 26 [plus or minus] 2 Ma. It is suggested that a mantle flow caused by the initiation of the subduction zone at [approximately] 25 Ma extends over a broader region (>750 km) than previously thought.</p>

Strike-slip structure and sedimentary basins of the southern Alpine Fault, Fiordland, New Zealand

2005 ◽  
Vol 117 (3) ◽  
pp. 411 ◽  
Author(s):  
Philip M. Barnes ◽  
Rupert Sutherland ◽  
Jean Delteil
Keyword(s):  
New Zealand ◽  
Sedimentary Basins ◽  
Strike Slip ◽  
Alpine Fault

scholarly journals An investigation of long-distance dispersal based on species native to both Tasmania and New Zealand

2001 ◽  
Vol 49 (3) ◽  
pp. 333 ◽  
Author(s):  
Gregory J. Jordan
Keyword(s):  
New Zealand ◽  
Molecular Clock ◽  
Common Species ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Dioecious Species ◽  
Tasman Sea ◽  
Different Types ◽  
Crude Approximation ◽  
Almost All

Some 200 species of plants are currently recognised as being native to both Tasmania and New Zealand. It is argued that dispersal across the 1500–2000-km Tasman Sea has occurred in all of these species. Almost all (187) are herbs and constitute over 20% of the herbaceous flora of Tasmania. Common species, non-dioecious species, species with very small seeds, species from aquatic, coastal or wet habitats and possibly species with hooked fruit are all over-represented among the disjunct species of herbs. The incidence of disjunct species also varies significantly among families. In contrast, fleshy fruited species, or species with plumes or very hairy disseminules, are not over-represented among the herbaceous disjunct species. These data are used to model the probability that a species (past or present) with given traits would show a within-species trans-Tasman disjunction, and it is inferred that this can be used to give a crude approximation of the rates of long-distance dispersal for different types of species. The model can be tested by using molecular clock methods and could be made more robust by incorporating equivalent data from other disjunct regions.

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.

Determining hydrological and soil mechanical parameters from multichannel surface-wave analysis across the Alpine Fault at Inchbonnie, New Zealand

2013 ◽  
Vol 11 (4) ◽  
pp. 435-448 ◽  
Author(s):  
L.A. Konstantaki ◽  
S. Carpentier ◽  
F. Garofalo ◽  
P. Bergamo ◽  
L.V. Socco
Keyword(s):  
New Zealand ◽  
Surface Wave ◽  
Mechanical Parameters ◽  
Wave Analysis ◽  
Alpine Fault

scholarly journals The fluid budget of a continental plate boundary fault: Quantification from the Alpine Fault, New Zealand

2016 ◽  
Vol 445 ◽  
pp. 125-135 ◽  
Author(s):  
Catriona D. Menzies ◽  
Damon A.H. Teagle ◽  
Samuel Niedermann ◽  
Simon C. Cox ◽  
Dave Craw ◽  
...  
Keyword(s):  
New Zealand ◽  
Plate Boundary ◽  
Boundary Fault ◽  
Continental Plate ◽  
Alpine Fault

Erosion rates of the New Zealand Southern Alps reflect long-term tectonics and transient climate

2021 ◽  
Author(s):  
Duna Roda-Boluda ◽  
Taylor Schildgen ◽  
Hella Wittmann-Oelze ◽  
Stefanie Tofelde ◽  
Aaron Bufe ◽  
...  
Keyword(s):  
New Zealand ◽  
Strike Slip ◽  
Southern Alps ◽  
Fault System ◽  
Tectonic Deformation ◽  
Seismic Cycle ◽  
Erosion Rates ◽  
Alpine Fault ◽  
Oblique Convergence

&lt;p&gt;The Southern Alps of New Zealand are the expression of the oblique convergence between the Pacific and Australian plates, which move at a relative velocity of nearly 40 mm/yr. This convergence is accommodated by the range-bounding Alpine Fault, with a strike-slip component of ~30-40 mm/yr, and a shortening component normal to the fault of ~8-10 mm/yr. While strike-slip rates seem to be fairly constant along the Alpine Fault, throw rates appear to vary considerably, and whether the locus of maximum exhumation is located near the fault, at the main drainage divide, or part-way between, is still debated. These uncertainties stem from very limited data characterizing vertical deformation rates along and across the Southern Alps. Thermochronology has constrained the Southern Alps exhumation history since the Miocene, but Quaternary exhumation is hard to resolve precisely due to the very high exhumation rates. Likewise, GPS surveys estimate a vertical uplift of ~5 mm/yr, but integrate only over ~10 yr timescales and are restricted to one transect across the range.&lt;/p&gt;&lt;p&gt;To obtain insights into the Quaternary distribution and rates of exhumation of the western Southern Alps, we use new &lt;sup&gt;10&lt;/sup&gt;Be catchment-averaged erosion rates from 20 catchments along the western side of the range. Catchment-averaged erosion rates span an order of magnitude, between ~0.8 and &gt;10 mm/yr, but we find that erosion rates of &gt;10 mm/yr, a value often quoted in the literature as representative for the entire range, are very localized. Moreover, erosion rates decrease sharply north of the intersection with the Marlborough Fault System, suggesting substantial slip partitioning. These &lt;sup&gt;10&lt;/sup&gt;Be catchment-averaged erosion rates integrate, on average, over the last ~300 yrs. Considering that the last earthquake on the Alpine Fault was in 1717, these rates are representative of inter-seismic erosion. Lake sedimentation rates and coseismic landslide modelling suggest that long-term (~10&lt;sup&gt;3&lt;/sup&gt; yrs) erosion rates over a full seismic cycle could be ~40% greater than our inter-seismic erosion rates. If we assume steady state topography, such a scaling of our &lt;sup&gt;10&lt;/sup&gt;Be erosion rate estimates can be used to estimate rock uplift rates in the Southern Alps. Finally, we find that erosion, and hence potentially exhumation, does not seem to be localized at a particular distance from the fault, as some tectonic and provenance studies have suggested. Instead, we find that superimposed on the primary tectonic control, there is an elevation/temperature control on erosion rates, which is probably transient and related to frost-cracking and glacial retreat.&lt;/p&gt;&lt;p&gt;Our results highlight the potential for &lt;sup&gt;10&lt;/sup&gt;Be catchment-averaged erosion rates to provide insights into the magnitude and distribution of tectonic deformation rates, and the limitations that arise from transient erosion controls related to the seismic cycle and climate-modulated surface processes.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

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