Volcanic ash, Redoubt A

Practical significance

Interpretation of remote sensing data. Analogues of other planets' atmospheric dust, and dust in comets, asteroids, and circumstellar shells.

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 constituent
68-76 wt% glass, plagioclase feldspar, hornblende, cps, opx, magnetite, ilmenite.
Color
Light gray
Particle size Fraunhofer: reff (μm)
4.1
Particle size Fraunhofer: veff
9.7
Size distribution plot:
Size Distribution Redoubt A
Size distribution table
size_redoubta.txt
Particle shape

Irregular

SEM/TEM images:
Redoubt A SEM Image 1
Redoubt A SEM Image 2
All SEM/TEM images (zip file)
sem_redoubt.zip
Scattering matrix (1) wavelength in nm
632.80 nm
Scattering matrix (1) table
matrix_redoubta_633nm.txt
Scattering matrix (1) plot:
Scattering matrix elements Redoubt A - 633 nm
Refractive index

Estimated to be in the range [1.48-1.56] + i0.0018.

Angle range (deg)
[3,173]
Reference/s
Muñoz et al., 2004