The Island Arc Setting of a New Zealand Cambrian Volcano-Sedimentary Sequence: Implications for the Evolution of the SW Pacific Gondwana Fragments

1995 ◽  
Vol 103 (6) ◽  
pp. 687-700 ◽  
Author(s):  
Carsten Münker ◽  
Roger A. Cooper
Keyword(s):  
New Zealand ◽  
Island Arc ◽  
Sedimentary Sequence ◽  
Sw Pacific ◽  
Arc Setting

scholarly journals Inverted Basins by Africa–Eurasia Convergence at the Southern Back-Arc Tyrrhenian Basin

Geosciences ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 117
Author(s):  
Maria Filomena Loreto ◽  
Camilla Palmiotto ◽  
Filippo Muccini ◽  
Valentina Ferrante ◽  
Nevio Zitellini
Keyword(s):  
Seismic Reflection ◽  
Magnetic Data ◽  
Normal Faults ◽  
Sedimentary Sequence ◽  
Initiation Zone ◽  
Arc Setting ◽  
Seismic Reflection Profiles ◽  
Back Arc ◽  
Flower Structures ◽  
Tyrrhenian Basin

The southern part of Tyrrhenian back-arc basin (NW Sicily), formed due to the rifting and spreading processes in back-arc setting, is currently undergoing contractional tectonics. The analysis of seismic reflection profiles integrated with bathymetry, magnetic data and seismicity allowed us to map a widespread contractional tectonics structures, such as positive flower structures, anticlines and inverted normal faults, which deform the sedimentary sequence of the intra-slope basins. Two main tectonic phases have been recognised: (i) a Pliocene extensional phase, active during the opening of the Vavilov Basin, which was responsible for the formation of elongated basins bounded by faulted continental blocks and controlled by the tear of subducting lithosphere; (ii) a contractional phase related to the Africa-Eurasia convergence coeval with the opening of the Marsili Basin during the Quaternary time. The lithospheric tear occurred along the Drepano paleo-STEP (Subduction-Transform-Edge-Propagator) fault, where the upwelling of mantle, intruding the continental crust, formed a ridge. Since Pliocene, most of the contractional deformation has been focused along this ridge, becoming a good candidate for a future subduction initiation zone.

scholarly journals Climate and Environmental Change in the SW-Pacific of the Last ~14, 000 Years Using Lipid Biomarkers in Sediments of a New Zealand Lake

2020 ◽  
Author(s):  
Sebastian Naeher ◽  
Thorsten Bauersachs ◽  
Valerie K. Stucker ◽  
Jonathan Puddick ◽  
Susanna A. Wood ◽  
...  
Keyword(s):  
New Zealand ◽  
Environmental Change ◽  
Lipid Biomarkers ◽  
Climate And Environmental Change ◽  
Sw Pacific

scholarly journals Petroleum resources in the Japanese island-arc setting

Episodes ◽  
1991 ◽  
Vol 14 (3) ◽  
pp. 236-241 ◽  
Author(s):  
Yoshiro Kikuchi ◽  
Satoshi Tono ◽  
Masaaki Funayama
Keyword(s):  
Island Arc ◽  
Japanese Island ◽  
Petroleum Resources ◽  
Arc Setting

An Archaeomagnetic Study of Hangi Stones in New Zealand

2021 ◽  
Author(s):  
◽  
Rimpy Kinger
Keyword(s):  
New Zealand ◽  
Radiocarbon Dating ◽  
Principal Component ◽  
Blocking Temperature ◽  
Radiocarbon Dates ◽  
The North ◽  
Sw Pacific ◽  
Archaeomagnetic Dating ◽  
Show Evidence ◽  
Temperature Spectra

<p>Burnt or fired archaeological artefacts often retain a record of the magnetic field in which they were last heated and cooled. Over the past four years we have collected oriented hangi stones from 10 archaeological sites spread across the North and South Islands of New Zealand. The stones vary in lithology from andesites, originating from the central North Island volcanoes, favoured by Maori for their durability and with remanent magnetization up to 30 A/m, to sandstones and schists from the main axial ranges, with magnetizations as weak as 10-4 A/m. Radiocarbon dating of charcoal fragments retrieved from amongst the stones indicates that the sites span from ca. 1400 AD to the present.  In all cases, we have independently oriented and retrieved several stones, and we have made several samples from each stone, either by drilling (standard cylindrical samples) or sawing (pseudo-cubes) in the laboratory. We have calculated site mean palaeomagnetic directions (Dec between 1.5o and 19.6o and Inc between -52.2o and -68.3o) from principal component analysis of thermal demagnetization and alternating field demagnetization data, discarding the data of stones that show evidence of disturbance after cooling. The directions are in good agreement with recently published palaeosecular variation records from lake sediments. We have carried out palaeointensity experiments using the Coe/Thellier method with pTRM and tail checks, and with selection criteria modified to the situation. Palaeointensities range from 50μT to 77μT. Rock magnetic experiments contribute to our understanding of the mineralogy, domain state and blocking temperature spectra.  We compare our data with predictions of the global field models ARCH3k and gufm1, and suggest that the addition of our new data will improve these models for the SW Pacific region for the most recent time period. Archaeomagnetic measurements are also used to date hangi sites by matching the palaeo-direction to an established archaeomagnetic dating model, NZPSV1k. Archaeomagnetic dating is used to resolve ambiguities in the calibration of radiocarbon dates, and shows up inconsistencies due to unreliable source material for radiocarbon dating. Archaeomagnetic dating and radiocarbon dating results are combined to give the best estimates of the best age of the hangi sites.</p>

Geochemistry of Archean carbonaceous cherts deposited at immature island-arc setting in the Pilbara Block, Western Australia

2002 ◽  
Vol 151 (1-2) ◽  
pp. 45-66 ◽  
Author(s):  
Kenichiro Sugitani ◽  
Koshi Yamamoto ◽  
Hideki Wada ◽  
S.S Binu-Lal ◽  
Masakazu Yoneshige
Keyword(s):  
Western Australia ◽  
Island Arc ◽  
Arc Setting

scholarly journals Evolution of Magmatism in the New Hebrides Island Arc and in Initial Back‐Arc Rifting, SW Pacific

2020 ◽  
Vol 21 (9) ◽  
Author(s):  
K. M. Haase ◽  
M. U. Gress ◽  
S. M. Lima ◽  
M. Regelous ◽  
C. Beier ◽  
...  
Keyword(s):  
Island Arc ◽  
Sw Pacific ◽  
New Hebrides ◽  
Back Arc

Gyrothyris williamsi sp. nov. and inter-relationships of some taxa from waters around New Zealand and the southern oceans (Rhynchonelliformea: Terebratelloidea)

2007 ◽  
Vol 98 (3-4) ◽  
pp. 425-435 ◽  
Author(s):  
Maria Aleksandra Bitner ◽  
Bernard L. Cohen ◽  
Sarah. L. Long ◽  
Bertrand Richer de Forges ◽  
Michiko Saito
Keyword(s):  
New Zealand ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Phylogenetic Reconstruction ◽  
Sister Group ◽  
Last Common Ancestor ◽  
Rdna Sequences ◽  
Sw Pacific ◽  
Rates Of Evolution ◽  
The Antarctic

ABSTRACTThis paper describes a terebratelloid articulate brachiopod, Gyrothyris williamsi sp. nov., based on 95 specimens from seamounts on the Lord Howe Rise, Coral Sea, SW Pacific Ocean. The new species is attributed to Gyrothyris on the basis of (a) morphological and growth trajectory similarities; (b) phylogenetic analyses of an alignment of DNA sequence (∼2900-sites) obtained from nuclear-encoded small- and large-subunit ribosomal RNA genes (SSU and LSU); and (c) the presence of a distinctive, two-part deletion in the LSU gene. It is distinguished morphologically from Gyrothyris mawsoni and its subspecies by both internal and external morphology and by its isolated geographical distribution, which extends the patchy, known range of this genus to an area some 2000 km north of its previous northern limit around New Zealand. Phylogenetic analyses of the rDNAs and of mitochondrial cox1 gene sequences (663 sites) confirm previous indications that the New Zealand endemic terebratelloid genera form a clade (Neothyris (Calloria, Gyrothyris, Terebratella), but the position of Terebratella with respect to Calloria and Gyrothyris remains weakly established. These sequences disagree inexplicably about the closeness of the relationship between Neothyris parva and N. lenticularis. Analyses of the first sequences from Calloria variegata, a species restricted to the Hauraki Gulf, New Zealand, are consistent with the possibility that it originated locally, and recently, from C. inconspicua. Magellania venosa from S. America/Falklands joins with Antarctic Magellania fragilis and M. joubini to form an rDNA clade that excludes Terebratalia as the putative sister-group of the New Zealand terebratelloid clade. The cox1 (but not the rDNA) sequences of the New Zealand clade pass a test for clock-like rates of evolution, and maximum likelihood pairwise distances suggest that if genetic isolation between the ancestor of Antarctic Magellania and the last common ancestor of the New Zealand terebratelloid clade was initiated by separation of the Antarctic and New Zealand plates ∼90 Mya, isolation from M. venosa was initiated earlier, perhaps ∼145 Mya. However, in the simple phylogenetic reconstruction presented here from cox1 sequences, S. American and Antarctic Magellania spp. do not yield a well-supported clade, perhaps because of differences in base composition.

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