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- W2500514892 abstract "Detailed mapping and geochronological investigations of edifice-forming materials reconstruct the growth history of Tongariro volcano, New Zealand, and subdivide the edifice into thirty six distinct units which are organised into twelve formations and constituent members. Twenty nine new 40Ar/39Ar age determinations, along with published K/Ar ages combined with volume estimates, petrographic observations and rock chemistry provide an integrated history of the volcano's growth through edifice-forming lavas and pyroclastic deposits. The oldest lava (512 ± 59 ka, 2 s.d.) is a small inlier of basaltic-andesite on Tongariro's NW sector that may reflect a nearly buried independent volcano. The next oldest material that can be confidently attributed to a Tongariro source is 304 ± 11 ka andesite, incorporated as boulders in late Pleistocene ejecta from the Tama Lakes area. In-situ lavas at Tongariro date from 230 ka to present, including numerous flows erupted during glacial periods and building the edifice unevenly due to emplacement against valley-filling ice bodies. Tongariro has a total edifice volume of ~90 km3, 19 km3 of which is represented by exposed map units, with glacial deposits amounting to <1 km3. The ring plain volume immediately adjacent to the volcano contains ~60 km3 of material. Sequential eruptive records, from 230 ka to present, reveal an irregular cyclicity in MgO concentrations over ~10–70 kyr intervals. During these cycles, rapid (≤10 kyr) increases in MgO concentrations to ≥5–9 wt% are inferred to reflect episodes of enhanced mafic magma replenishment, with maxima at ~230, ~160, ~117, ~88, ~56, ~35, ~17.5 ka and during the Holocene, which are each followed by gradual declines to ~2–5 wt%. Field evidence, including extensive moraines and U-shaped valleys, and lava textures, implies repeated occupation of valleys on Tongariro by major glaciers and possibly ice caps. During periods of major ice coverage, which generally correlate with global cold climate/glacial Marine Isotope Stages, edifice-building rates on Tongariro were only 17–26% of those during warmer climatic periods. Because the changes in edifice-building rates do not coincide with changes in the magmatic system, these contrasts are inferred to reflect a preservation bias whereby materials erupted onto ice were contemporaneously (or subsequently, as ice masses melted) conveyed to the ring plain as debris rather than building the edifice. Although the Tongariro edifice is smaller than that of neighbouring Ruapehu (~150 km3), the exposed edifice materials on Tongariro record a longer and more complex growth history. The wider geographic distribution of <50 ka vent locations at Tongariro reflects greater rifting rates than at Ruapehu." @default.
- W2500514892 created "2016-08-23" @default.
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- W2500514892 date "2020-10-01" @default.
- W2500514892 modified "2023-09-26" @default.
- W2500514892 title "A high resolution 40Ar/39Ar lava chronology and edifice construction history for Tongariro volcano, New Zealand" @default.
- W2500514892 cites W1500787922 @default.
- W2500514892 cites W1567059037 @default.
- W2500514892 cites W161627192 @default.
- W2500514892 cites W1616577258 @default.
- W2500514892 cites W1675451487 @default.
- W2500514892 cites W182155117 @default.
- W2500514892 cites W1896687249 @default.
- W2500514892 cites W1965240661 @default.
- W2500514892 cites W1969193331 @default.
- W2500514892 cites W1969859799 @default.
- W2500514892 cites W1974399179 @default.
- W2500514892 cites W1976879065 @default.
- W2500514892 cites W1980908182 @default.
- W2500514892 cites W1991456370 @default.
- W2500514892 cites W1991580224 @default.
- W2500514892 cites W1993916058 @default.
- W2500514892 cites W1997158601 @default.
- W2500514892 cites W2004169722 @default.
- W2500514892 cites W2004973269 @default.
- W2500514892 cites W2007539566 @default.
- W2500514892 cites W2009958419 @default.
- W2500514892 cites W2010943359 @default.
- W2500514892 cites W2017154153 @default.
- W2500514892 cites W2017372183 @default.
- W2500514892 cites W2022821957 @default.
- W2500514892 cites W2023221508 @default.
- W2500514892 cites W2024089485 @default.
- W2500514892 cites W2026602338 @default.
- W2500514892 cites W2038072959 @default.
- W2500514892 cites W2038234229 @default.
- W2500514892 cites W2038641152 @default.
- W2500514892 cites W2040922130 @default.
- W2500514892 cites W2044812716 @default.
- W2500514892 cites W2045845416 @default.
- W2500514892 cites W2050453011 @default.
- W2500514892 cites W2056087521 @default.
- W2500514892 cites W2060234235 @default.
- W2500514892 cites W2061646834 @default.
- W2500514892 cites W2068873158 @default.
- W2500514892 cites W2068894410 @default.
- W2500514892 cites W2078816475 @default.
- W2500514892 cites W2078838424 @default.
- W2500514892 cites W2079317589 @default.
- W2500514892 cites W2082973736 @default.
- W2500514892 cites W2083565302 @default.
- W2500514892 cites W2086423957 @default.
- W2500514892 cites W2086804162 @default.
- W2500514892 cites W2090578063 @default.
- W2500514892 cites W2095175055 @default.
- W2500514892 cites W2097430011 @default.
- W2500514892 cites W2104736554 @default.
- W2500514892 cites W2106563361 @default.
- W2500514892 cites W2118153886 @default.
- W2500514892 cites W2123803462 @default.
- W2500514892 cites W2128390854 @default.
- W2500514892 cites W2129221669 @default.
- W2500514892 cites W2145496138 @default.
- W2500514892 cites W2153326760 @default.
- W2500514892 cites W2166515343 @default.
- W2500514892 cites W2173794629 @default.
- W2500514892 cites W2243799563 @default.
- W2500514892 cites W2287139546 @default.
- W2500514892 cites W2302132648 @default.
- W2500514892 cites W2317182645 @default.
- W2500514892 cites W2339161270 @default.
- W2500514892 cites W2340197136 @default.
- W2500514892 cites W2346306933 @default.
- W2500514892 cites W2418468025 @default.
- W2500514892 cites W2463730677 @default.
- W2500514892 cites W2495925216 @default.
- W2500514892 cites W2607173620 @default.
- W2500514892 cites W2607483962 @default.
- W2500514892 cites W2752500783 @default.
- W2500514892 cites W2762505430 @default.
- W2500514892 cites W2773217588 @default.
- W2500514892 cites W2800361010 @default.
- W2500514892 cites W2804322489 @default.
- W2500514892 cites W2886216967 @default.
- W2500514892 cites W2890276689 @default.
- W2500514892 cites W2960046396 @default.
- W2500514892 cites W2998805375 @default.
- W2500514892 cites W3010280621 @default.
- W2500514892 cites W4211131589 @default.
- W2500514892 cites W2020558382 @default.