Thirty oriented fresh block samples were collected from ten suitable sites of the outcropping andesite rock formation to study their Petrographical characteristics and Magnetic properties. The analysis of these rocks around Khairmalia shows that the magnetite crystals are fresh and are in perfect shape. These crystals are present in sufficient quantity i.e. measured as 10 to 20% in various rock...

Introduction: Although mafic components of dominantly intermediate to silicic ignimbrites are rather common, voluminous, dominantly mafic ignimbrites are rare (e.g., Smith, 1979; cf. Freundt and Schmincke, 1995). Volcán Villarrica, the most active composite volcano in South America, located in the Southern Andean Volcanic Zone (SAVZ, López-Escobar and Moreno, 1994a), has produced two such ignim...

New Zealand’s newest and most active volcano, Mt. Ngauruhoe in the Taupo Volcanic Zone, produced andesite fl ows in 1949 and 1954, and avalanche deposits in 1975. Potassium-argon “dating” of fi ve of these fl ows and deposits yielded K-Ar model “ages” from <0.27 Ma to 3.5±0.2 Ma. “Dates” could not be reproduced, even from splits of the same samples from the same fl ow, the explanation being var...

Hornblende occurs in some andesitic and basaltic rocks of calc-alkaline affini1y, where it is commonly associated with olivine. The texture, eruption history, and composition are interpreted to indicate that hornblende commonly forms as a product of reaction between olivine and basaltic and andesitic liquids. The natural hornblendes probably formed within the crust at temperatures between 960o ...

BWQC-1, a coarse-grained basaltic andesite, Westfield, MA. Each spectral channel has been normalized to the total emission intensity of its spectral region. LIBS ANALYSIS OF MINOR ELEMENTS IN GEOLOGIC SAMPLES. J. M. Tucker, M. D. Dyar, S. M. Clegg, M. W. Schaefer, R. C. Wiens, J. E. Barefield II. Department of Astronomy, Amherst College, Amherst, MA 01002, [email protected], Department of A...

In the present study, andesite basalt originated from deposit site ?Donje Jarinje?, Serbia, was examined as a potential raw material for high-density ceramics production. The production of included dry milling, homogenization, cold isostatic pressing and sintering in air. To determine optimal processing parameters conducted at 1040, 1050, 1060, 1070 1080?C, afterwards duration varied 30 to 240m...