Facts and Figures

name of sample

Redoubt A

origin

Redoubt volcano, Cook Inlet, Alaska, USA, 283 km southwest of Anchorage.

The particles are from the 1989-1990 eruption and were collected 10 km from

the volcano. The coarse fraction was removed by sieving.

main constituents

68-76 wt % glass, plagioclase feldspar, hornblende, cps, opx, magnetite, ilmenite

particle size

distributions measured with laser diffraction

r_eff=4.1 micrometer, v_eff =9.7

particle shape

irregular (SEM image)

refractive index

estimated to be around:

1.48-1.56 -  i0.0018

color 

light grey powder

scattering matrix

from 3-174 degrees scattering angle

wavelength

632.8 nm (figure)

article

Scattering matrices of volcanic ash particles of Mnt. St. Helens, Redoubt, and Mount

Spurr volcanoes

Muñoz O, Volten H, Hovenier JW. Veihelmann B, van der Zande WJ, Waters LBFM, Rose WI

Journal of Geophysical Research, 109,10.1029/2004JD004684,2004