Stratigraphy and geochemistry of the Turoa area, with implications for andesite petrogenesis at Mt Ruapehu, Taupo Volcanic Zone, New Zealand

Abstract Detailed mapping and sampling on Turoa ski‐field and surrounding areas on Mt Ruapehu has enabled identification of individual flow packets that represent small scale eruptive events during the major cone‐building episodes previously identified on Ruapehu by Graham & Hackett. The area is dominated by plagioclase‐pyroxene‐phyric andesitic lavas of Mangawhero Formation, which are petrographically and geochemically typical of post‐120 ka Ruapehu lavas. Although the lavas are from a relatively small area of the volcano, geochemical and isotopic compositions show a range in variation similar to that observed for the entire volcano. Examination of geochemical variations between individual flow packets and also between sequential lava flows indicates complex processes of assimilation and influx of “new”, variably evolved and fractionated magmas into high level magma chambers. These chambers are most likely heterogeneous, and individual eruptions may also sample compositionally distinct regions of the sam...

[1]  R. Stewart,et al.  A fifty year perspective of magmatic evolution on Ruapehu Volcano, New Zealand: verification of open system behaviour in an arc volcano , 1999 .

[2]  V. Neall,et al.  The volcanic history of Ruapehu during the past 2 millennia based on the record of Tufa Trig tephras , 1997 .

[3]  K. Hirose,et al.  Geochemical Variations in Vanuatu Arc Lavas: the Role of Subducted Material and a Variable Mantle Wedge Composition , 1997 .

[4]  N. Mortimer,et al.  Basement geology of Taranaki and Wanganui Basins, New Zealand , 1997 .

[5]  D. Shelley,et al.  Field characteristics, petrography, and geochronology of the Hohonu Batholith and the adjacent Granite Hill Complex, North Westland, New Zealand , 1997 .

[6]  H. Keppler.  Constraints from partitioning experiments on the composition of subduction-zone fluids , 1996, Nature.

[7]  M. Drummond,et al.  Insights into the volcanic arc mantle wedge from magnesian lavas from the Kamchatka arc , 1996 .

[8]  R. Stewart,et al.  Magma mingling in an andesite pyroclastic flow of the Pourahu Member, Ruapehu volcano, New Zealand , 1995 .

[9]  J. Cole,et al.  Petrology and petrogenesis of volcanic rocks from the Taupo Volcanic Zone: a review , 1995 .

[10]  F. Ryerson,et al.  Mineral-aqueous fluid partitioning of trace elements at 900°C and 2.0 GPa: Constraints on the trace element chemistry of mantle and deep crustal fluids , 1995 .

[11]  J. Davidson,et al.  Petrology of Calc-Alkaline Lavas at Volc´n Ollagüe and the Origin of Compositional Diversity at Central Andean Stratovolcanoes , 1994 .

[12]  E. Ito,et al.  O, Sr, Nd and Pb isotopic composition of the Kasuga Cross-Chain in the Mariana Arc: A new perspective on the K-h relationship , 1993 .

[13]  H. Rollinson.  Using Geochemical Data: Evaluation, Presentation, Interpretation , 1993 .

[14]  S. Eggins,et al.  High field strength and transition element systematics in island arc and back-arc basin basalts: Evidence for multi-phase melt extraction and a depleted mantle wedge , 1993 .

[15]  B. Gulson,et al.  Petrogenesis of Late Cenozoic volcanic rocks from the Taupo Volcanic Zone, New Zealand, in the light of new lead isotope data , 1992 .

[16]  R. Stewart,et al.  Pb-Nd-Sr isotopic compositions and trace element characteristics of young volcanic rocks from Egmont Volcano and comparisons with basalts and andesites from the Taupo Volcanic Zone, New Zealand , 1992 .

[17]  A. Hofmann,et al.  Potassium, rubidium, and cesium in the Earth and Moon and the evolution of the mantle of the Earth , 1992 .

[18]  F. McDermott,et al.  Destructive margin magmatism and the contributions from the mantle wedge and subducted crust , 1991 .

[19]  M. Menzies,et al.  Evidence from Muriah, Indonesia, for the Interplay of Supra-Subduction Zone and Intraplate Processes in the Genesis of Potassic Alkaline Magmas , 1991 .

[20]  M. McCulloch,et al.  Geochemical and geodynamical constraints on subduction zone magmatism , 1991 .

[21]  M. McCulloch,et al.  Meta-igneous granulite xenoliths from Mount Ruapehu, New Zealand: Fragments of altered oceanic crust? , 1990 .

[22]  J. Cole,et al.  The petrology, phase relations and tectonic setting of basalts from the taupo volcanic zone, New Zealand and the Kermadec Island arc - havre trough, SW Pacific , 1990 .

[23]  J. Cole.  Structural control and origin of volcanism in the Taupo volcanic zone, New Zealand , 1990 .

[24]  V. Neall,et al.  The Murimotu Formation ― 9500 year old deposits of a debris avalanche and associated lahars, Mount Ruapehu, North Island, New Zealand , 1989 .

[25]  I. Graham,et al.  Buchitic metagreywacke xenoliths from Mount Ngauruhoe, Taupo Volcanic Zone, New Zealand , 1988 .

[26]  J. Woodhead.  The Origin of Geochemical Variations in Mariana Lavas: A General Model for Petrogenesis in Intra-Oceanic Island Arcs? , 1988 .

[27]  I. Graham.  Petrography and origin of metasedimentary xenoliths in lavas from Tongariro Volcanic Centre , 1987 .

[28]  C. Hawkesworth,et al.  The Pleistocene-Recent Tonga-Kermadec Arc Lavas: Interpretation of New Isotopic and Rare Earth Data in Terms of a Depleted Mantle Source Model , 1987 .

[29]  W. Hackett,et al.  Petrology of Calc-alkaline Lavas from Ruapehu Volcano and Related Vents, Taupo Volcanic Zone, New Zealand , 1987 .

[30]  Y. Tatsumi,et al.  Chemical characteristics of fluid phase released from a subducted lithosphere and origin of arc magmas: Evidence from high-pressure experiments and natural rocks , 1986 .

[31]  A. Tsuchiyama.  Dissolution kinetics of plagioclase in the melt of the system diopside-albite-anorthite, and origin of dusty plagioclase in andesites , 1985 .

[32]  J. Pearce.  Role of the sub-continental lithosphere in magma genesis at active continental margins , 1983 .

[33]  J. Foden.  The Petrology of The Calcalkaline Lavas of Rindjani Volcano, East Sunda Arc: a Model for Island Arc Petrogenesis , 1983 .

[34]  D. C. Gerlach,et al.  Origin of calc-alkaline series lavas at Medicine Lake Volcano by fractionation, assimilation and mixing , 1982 .

[35]  J. Gill.  Orogenic Andesites and Plate Tectonics , 1981 .

[36]  D. DePaolo.  Trace element and isotopic effects of combined wallrock assimilation and fractional crystallization , 1981 .

[37]  S. Taylor,et al.  Chemical characteristics of island-arc basalts: Implications for mantle sources , 1980 .

[38]  A. McBirney,et al.  Mixing and unmixing of magmas , 1980 .

[39]  A. Saunders,et al.  Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas , 1980 .

[40]  A. Mateen,et al.  An outline of the geology and geochemistry, and the possible petrogenetic evolution of the volcanic rocks of the Tonga-Kermadec-New Zealand island arc , 1977 .

[41]  J. Eichelberger.  Origin of andesite and dacite: Evidence of mixing at Glass Mountain in California and at other circum-Pacific volcanoes , 1975 .

[42]  R. Hamilton,et al.  Seismicity and structure of North Island, New Zealand , 1968 .

[43]  R. Stewart,et al.  Petrogenesis of High-K Arc Magmas: Evidence from Egmont Volcano, North Island, New Zealand , 1999 .

[44]  B. Hobden.  Modelling magmatic trends in time and space: Eruptive and magmatic history of Tongariro Volcanic Complex, New Zealand , 1997 .

[45]  C. M. Gray,et al.  Strontium isotopic and trace element heterogeneity in the plains basalts of the Newer Volcanic Province, Victoria, Australia , 1997 .

[46]  V. Neall,et al.  Tephrostratigraphic studies at Tongariro Volcanic Centre, New Zealand: An overview , 1996 .

[47]  D. Peate,et al.  Tectonic Implications of the Composition of Volcanic Arc Magmas , 1995 .

[48]  S. Eggins,et al.  Subduction zone magmatism , 1995 .

[49]  D. Lowe,et al.  A review of late Quaternary silicic and some other tephra formations from New Zealand: Their stratigraphy, nomenclature, distribution, volume, and age , 1990 .

[50]  B. Houghton,et al.  A facies model for a quaternary andesitic composite volcano: Ruapehu, New Zealand , 1989 .

[51]  R. W. Le Maitre,et al.  A Classification of igneous rocks and glossary of terms : recommendations of the International Union of Geological Sciences Subcommission on the Systematics of Igneous Rocks , 1989 .

[52]  C. Hawkesworth,et al.  Elemental and isotopic variations in subduction related basalts: evidence for a three component model , 1988 .

[53]  T. Grove,et al.  Petrogenesis of Andesites , 1986 .

[54]  W. Hackett.  Geology and Petrology of Ruapehu Volcano and Related Vents , 1985 .

[55]  P. Hamilton,et al.  Sm—Nd systematics of Lewisian gneisses: implications for the origin of granulites , 1979, Nature.

[56]  R. Adams,et al.  Subcrustal earthquakes beneath New Zealand; Locations determined with a laterally inhomogeneous velocity model , 1977 .