Zobrazeno 1 - 10
of 12
pro vyhledávání: '"Jim Cole"'
Publikováno v:
Journal of Volcanology and Geothermal Research. :27-36
Hornblende, cummingtonite, and biotite δD values from rhyolitic and mingled/mixed mafic rocks from the Central Taupo Volcanic Zone were determined in an effort to characterize the isotopic composition of the dissolved fluid of magmas in this predomi
Publikováno v:
Journal of Petrology. 51:1477-1505
The ~140 Ma Halfmoon Pluton of Stewart Island, New Zealand, provides direct evidence for a number of physico-chemical processes that operate at depth within active arc settings. It is characterized by a sequence of mingled mafic sheets and enclaves t
Publikováno v:
Contributions to Mineralogy and Petrology. 161:129-151
The Matahina Ignimbrite (~160 km3 rhyolite magma, 330 ka) was deposited during a caldera-forming eruption from the Okataina Volcanic Centre, Taupo Volcanic Zone (TVZ), New Zealand. Juvenile clasts are divided into three groups: Group (1) the dominant
Publikováno v:
Contributions to Mineralogy and Petrology. 160:609-629
Slab-derived aqueous fluid components (Ba, Cl) correlate well with oxygen fugacity, and other well-defined characteristics of silicic magmas in the Taupo Volcanic Zone (TVZ) between a cold-wet-oxidizing magma type [R1: amphibole ± biotite; high Sr,
Publikováno v:
Journal of Petrology. 49:2245-2276
Rhyolites generated in the modern Taupo Volcanic Zone (TVZ), New Zealand, have previously been interpreted as having evolved by a combination of extensive fractional crystallization of mantle-derived mafic magmas and limited crustal assimilation (up
Publikováno v:
Chemical Geology. 148:21-41
Plutonic rock fragments occur as rare accessory lithics within some of the ignimbrites erupted from calderas and caldera complexes in central Taupo Volcanic Zone (TVZ), New Zealand. The two main suites of plutonic lithics are: (1) medium to fine-grai
Autor:
Jim Cole
Publikováno v:
New Zealand Journal of Geology and Geophysics. 21:143-153
The ‘Kiwitahi Volcanics’ form a chain on the west side of the Hauraki Depression. Individual cones and flows occur at Waiheke Island, Miranda, Pukekarnaka, Tahuna, Maungatapu, Kiwitahi, Maungakawa, and Te Tapui. Maungatautari is a volcanic comple
Autor:
Jim Cole
Publikováno v:
Journal of Volcanology and Geothermal Research. 3:121-153
The Tongariro volcanic centre comprises four major andesite massifs, Kakaramea, Pihanga, Tongariro and Ruapehu, and four smaller cones and flows, Maungakatote, Pukeonake, Hauhungatahi and Ohakune. Older lavas from Kakaramea, Pihanga and Tongariro wer
Publikováno v:
Chemical Geology. 38:255-274
Two types of basalt (a high-Al basalt associated with the rhyolitic centres north of Taupo and a “low-Al” basalt erupted from Red Crater, Tongariro Volcanic Centre) and five types of andesite (labradorite andesite, labradorite-pyroxene andesite,
Publikováno v:
New Zealand Journal of Geology and Geophysics. 11:793-828
In the three areas studied, the McMurdo volcanics have been subdivided into four formations: Melania (oldest, and predominantly basaltic); Aurora Trachyte; Nubian Basalt; and the Trachyte Hill Formation. Tentative correlations have been made among th