کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
4714966 1638462 2007 26 صفحه PDF سفارش دهید دانلود رایگان
عنوان انگلیسی مقاله ISI
Multiple rhyolite magmas and basalt injection in the 17.7 ka Rerewhakaaitu eruption episode from Tarawera volcanic complex, New Zealand
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
سفارش ترجمه تخصصی
با تضمین قیمت و کیفیت
خدمات تولید محتوا

این مقاله ISI می تواند منبع ارزشمندی برای تولید محتوا باشد.

  • تولید محتوا برای سایت و وبلاگ
  • تولید محتوا برای کتاب
  • تولید محتوا برای نشریات و روزنامه ها
  • و...

پایگاه «دانشیاری» آمادگی دارد با همکاری مجموعه «شهر محتوا» با استفاده از این مقاله علمی، برای شما به زبان فارسی، تولید محتوا نماید.

تولید محتوا
با 10 درصد تخفیف ویژه دانشیاری
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
پیش نمایش صفحه اول مقاله
Multiple rhyolite magmas and basalt injection in the 17.7 ka Rerewhakaaitu eruption episode from Tarawera volcanic complex, New Zealand
چکیده انگلیسی

The 17.7 ka Rerewhakaaitu eruption episode (volume ∼ 5 km3 DRE rhyolite magma) was the second of five major episodes that have built the Tarawera volcanic complex in the Okataina Volcanic Centre over the past 22 kyr. The Rerewhakaaitu episode produced a widespread tephra fall deposit, associated proximal pyroclastic flow deposits, and voluminous rhyolite lava extrusions. Two different rhyolite magmas (T1 and T2) were simultaneously erupted from the main vent area throughout much of the eruption episode. T1 magma was a crystal-poor orthopyroxene-hornblende rhyolite that is highly evolved (whole rock SiO2 = 77 wt.%), with a moderate temperature (∼ 760 °C, based on Fe–Ti oxides). T2 is a crystal-rich biotite-hornblende rhyolite that is less evolved (SiO2 = 75 wt.%), with a Fe–Ti oxide temperature of ∼ 700 °C. Ejecta from the simultaneous and sequential eruption of these two magmas include some pumice clasts with mixed (hybrid) and mingled glass compositions and crystal populations. A third rhyolite magma (T3) was extruded from another vent 3 km distant to form an apparently contemporaneous lava dome. T3 was the least evolved (SiO2 = 74 wt.%) and hottest (∼ 820 °C) of the three magmas. Saturation pressures calculated using dissolved H2O and CO2 contents of melt inclusions in quartz crystals indicate that T2 magma stagnated and crystallised at about 12 km depth, while small quartz crystals in T1 magma grew during ascent through ∼ 8 km depths.Some T1 and T2 rhyolite clasts contain vesicular brown blebs with widely variable (andesite to rhyolite) glass compositions, accompanied by olivine, clinopyroxene and calcic plagioclase crystals that are interpreted as xenocrysts derived from injected basalt. Temperatures over 1000 °C estimated from pyroxene phase equilibria in these clasts reflect intrusion of the more mafic magma, which is now identified as the priming and triggering mechanism for three of the four post-22 ka Tarawera rhyolite eruption episodes. However, the rhyolite magma bodies and conduits modelled for each episode have considerable differences in characteristics and geometry. Our preferred model for the Rerewhakaaitu episode is that eruptions occurred from three laterally and vertically isolated rhyolite magma bodies that were initially primed and triggered by basalt intrusion during a regional rifting event. The ascending hotter and less viscous T1 rhyolite magma intersected and further invigorated a stagnant pond of cooler, denser and more viscous T2 magma, and lubricated its transport to the surface.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Volcanology and Geothermal Research - Volume 164, Issues 1–2, 1 July 2007, Pages 1–26
نویسندگان
, , , , , , ,
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
سفارش ترجمه تخصصی
با تضمین قیمت و کیفیت