Andradite and andradite-grossular solid solutions in very low-grade regionally metamorphosed rocks in Southern New Zealand

  title={Andradite and andradite-grossular solid solutions in very low-grade regionally metamorphosed rocks in Southern New Zealand},
  author={Douglas S. Coombs and Yosuke Kawachi and Bruce F. Houghton and G. Hyden and Ian J. Pringle and J. G. Williams},
  journal={Contributions to Mineralogy and Petrology},
AbstractAlmost pure andradite and intermediate members of the andradite-grossular series (gros40–49, and 47–54, py0–3, alm0–3, spess0–2, hydrogarnet0–3), often framboidal in habit, are widespread in metabasites including lavas, minor intrusions, and volcanic sandstones and breccias metamorphosed under prehnite-pumpellyite and pumpellyite-actinolite facies conditions, possibly extending into the zeolite facies. Coexisting phases include iron-rich epidotes (100 Fe*/Fe*+Al=22–34), pumpellyite… Expand
Low-grade metamorphism of the Brook Street Volcanics, D'Urville Island, New Zealand
Abstract Basic lavas, pyroclastics, and labile sediments, together with ultramafic and gabbroic intrusives, comprising the Lower Permian volcanic arc sequence of the Brook Street Volcanics at westExpand
Non-mafic rocks in the greenschist, blueschist and eclogite facies
Abstract Mineral relations in pelitic rocks having undergone regional metamorphism in greenschist and amphibolite facies are reasonably well understood in terms of reactions in the felsic modelExpand
Low-grade metamorphism of the Takitimu Group, western Southland, New Zealand
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Secondary Ca-Al silicates as low-grade alteration products of granitoid biotite
Secondary Ca-Al silicates, including andradite-grossular garnet, epidote, pumpellyite, and prehnite are shown to be extremely widespread as low-grade alteration products of granitoid biotite. All mayExpand
Prehnite–pumpellyite to greenschist facies transition, Smartville Complex, near Auburn, California
The Smartville Complex is a late Jurassic, rifted volcanic arc in the northern Sierra Nevada, California. Near Auburn, California, it consists of a lower volcanic unit, dominated by basaltic flows,Expand
Epidote Group Minerals in Low-Medium Pressure Metamorphic Terranes
Epidote group minerals are common in metamorphosed mafic to intermediate igneous rocks, quartzofeldspathic sediments and calc-alumina silicate (marl) rocks of higher grade zeolite to medium gradeExpand
Conditions and Timing of Pumpellyite–Actinolite-facies Metamorphism in the Early Mesozoic Frontal Accretionary Prism of the Madre de Dios Archipelago (Latitude 50°20′S; Southern Chile)
The Madre de Dios Metamorphic Complex (MDMC) in southern Chile is a fossil frontal accretionary prism, which is mainly composed of metapsammopelitic rocks, intercalations of oceanic rocks (greenstoneExpand
Paleoproterozoic metamorphism of metaultramafic rocks in the Miyun area, northeastern North China Craton
Abstract The Miyun area is located in the northwestern border of the Eastern Block of the North China Craton, where the metaultramafic rocks occur as intrusive bodies, some of which display cumulateExpand
The geochemistry, origin, and tectonic significance of rodingites from the Dun Mountain Ultramafics, d'Urville island, New Zealand
Numerous rodingite dikes and rodingitised tectonic blocks occur within serpentinised harzburgite of the Dun Mountain Ultramafics, D’Urville Island, New Zealand. The rodingites formed duringExpand


Zonation of low grade regional metamorphic rocks, Nambucca slate belt, northeastern New South Wales
Abstract Crystallization of stilpnomelane and pumpellyite, disappearance of prehnite and development of assemblages containing the pair pumpellyite‐actinolite, and disappearance of pumpellyite,Expand
Zeolite and prehnite-pumpellyite facies in south central Puerto Rico
The intermediate lavas and pyroclastic rocks of south central Puerto Rico have been subjected to about four kilometers of burial. Despite shallow burial the mineralogy of these rocks hasExpand
Pumpellyite-actinolite and contiguous facies metamorphism in part of Upper Wakatipu District, South Island, New Zealand
Abstract Metamorphic minerals from pumpellyite-actinolite and contiguous facies in the Upper Wakatipu district, South Island, New Zealand, have been studied using optical and X-ray diffractionExpand
Clinopyroxenes in the tawhiroko tholeiitic dolerite at Moeraki, north-eastern Otago, New Zealand
Clinopyroxenes from various lithologic units in a single tholeiitic dolerite intrusion 50 m thick were analysed with the electron microprobe. Microphenocrysts of augite in the chilled marginal rockExpand
The Al-Fe(III)epidote miscibility gap in a metamorphic profile through the penninic series of the Tauern window, Austria
The compositional variations in epidotes, Ca2Al2(Fe3+, Al)-Si3O12(OH), from a prograde Mesozoic rock series in the Eastern Alps, Austria, are systematically related to metamorphic grade and theExpand
Petrological and Geochemical Study of Spilites and Associated Rocks from St. John, U.S. Virgin Islands
A continuous section of extrusive and intrusive rocks has been recovered through a drill core of about 2430 ft that was taken at St. John, Virgin Islands. This study is confined to the upper 1180 ftExpand
Comparison of the Mineralogy and Phase Relations of Blueschists from the North Cascades, Washington, and Greenschists from Otago, New Zealand
Blueschists of the Shuksan unit can be related to greenschists from Otago by the following general reaction: crossite + epidote = albite + actinolite + iron oxide + H 2 O Greenschists within theExpand
Phase relations of biotite and stilpnomelane in the greenschist facies
AbstractPhase relations of biotite and stilpnomelane and associated silicate minerals have been studied in rocks of the greenschist facies, chiefly from Otago, New Zealand and western Vermont, butExpand
The greenschist facies in part of eastern Otago, New Zealand
AbstractRocks of the greenschist facies in eastern Otago, New Zealand, have been investigated in an area some thirteen to sixteen kilometers wide and sixty-five kilometers long extendingExpand
Geology and petrochemistry of weakly metamorphosed rocks in the upper Wakatipu district, southern New Zealand
Abstract The area near the head of Lake Wakatipu lies between the Livingstone Fault to the west, and the Otago Schist terrane to the east. The area is divided into three major tectonic slices orExpand