Minerals in Volcanic Ash 1: Primary Minerals and Volcanic Glass

نویسندگان

  • MITSUHIRO NAKAGAWA
  • TSUKASA OHBA
چکیده

Volcanic ash is fragments of magma, and consists of minerals and volcanic glass. These materials in the ash can provide important information on the nature of the magma, because chemical compositions of magma usually show distinct features in each volcano, and because assemblages and compositions of minerals reflect their host melt. Using assemblages and chemical compositions of minerals and glass chemistry, it may be possible to correlate volcanic ash distributed over a wide area. In addition, we may identify the source volcano of the ash. We show several examples of correlating volcanic ash and determining source volcanoes. Moreover, it is possible to discuss magmatic and eruption processes recorded in volcanic ash. We also show several examples of discussing eruption sequences and magma mixing processes using analysis of volcanic ash.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Immersion freezing of supercooled water drops containing glassy volcanic ash particles

The freezing temperatures of hundreds of water drops with radii 20–50 lm containing known average concentrations of suspended, mostly micronto submicron-sized, volcanic ash particles composed of SiO2-rich glass were recorded using optical microscopy. As expected, the ash suppresses supercooling, and in contrast to earlier studies of much larger ash particles, the median freezing temperature cle...

متن کامل

20. Origin and Alteration of Volcanic Ash and Pelagic Brown Clay, Deep Sea Drilling Project Leg 62, North-central Pacific

Volcanic ash was recovered from lower Aptian to Albian deposits from DSDP Sites 463, 465, and 466; pelagic clay of the upper Pleistocene to Upper Cretaceous was recovered mainly from Site 464, with minor amounts at Sites 465 and 466 (Figs. 1 and 2). We present X-ray-mineralogy data on pelagic clay and altered volcanic ash recovered from the four Leg 62 sites (Table 1; Fig. 1). In addition, two ...

متن کامل

Refuting the evidence for an earlier birth of the Taklimakan Desert.

In a recent issue of PNAS, Zheng et al. (1) report a “Late Oligocene–Early Miocene age” of the Taklimakan Desert in northwest China. Their age was based on Ar/Ar dating of biotites and U–Pb dating of zircons from layers within the Xiyu Formation, which they interpreted as “volcanic ash.” This chronology effectively extends the formation of the Taklimakan Desert from ∼5 Ma, as recently reported ...

متن کامل

Absorption of copper (Cu2+) and nickel (Ni2+) from aqueous solutions by volcanic ash soil

Introduction: Natural volcanic ash soil is one of minerals whose major contents are metal oxides. In this study absorption of copper (Cu2+) and nickel (Ni2+) on natural volcanic ash soil has been investigated at 27±1c as a function of PH, metal concentration, contact time and the amount of sorbet, using batch experiments. Methods: The necessary samples of natural volcanic ashes were collected...

متن کامل

Is the Chemistry of the Bedrocks at Meridiani Planum Indicative of a Volcanic

Introduction: The Mars Exploration Rover Opportunity has obtained chemical and mineralogical data for exposed bedrocks at Meridiani Planum on Mars. In using these data to formulate a diagenetic model for the bedrocks, a clear distinction must be made between the primary inputs into the rocks and products of secondary processes. The chemical composition of the Meridiani bedrocks provides the mos...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2003