Aca - Departamento de Física - Universidad Técnica Federico Santa ...

∗
V Encuentro Sud Americano de Colisiones Inelásticas en la Materia
Needles
Counts (a.u)
10000
8000
6000
4000
2000
∗
∗
∗
∗
∗
∗ ∗
∗ ∗ ∗
∗ ∗
∗
∗
∗
∗
∗
∗ SiO 2
∗ Al 2 O 3
∗ K 2 O
∗ Na 2 O
∗
∗
∗
0
20 40 60 80
2θ (degree)
Figure 2. Secondary electron (SE) SEM micrograph
of the first eruption ash.
Figure 4. x-ray diffraction of first eruption ash.
Pores
25000
20000
∗
∗ SiO 2
∗ Al 2 O 3
∗ Na 2 O
Counts (a.u)
15000
10000
Rough
Surface
5000
0
∗
∗
∗
∗
∗
∗
∗
∗
20 40 60 80
2θ (degree)
Figure 3. Backscattered electron (BSE) SEM micrograph
of the second eruption ash.
The element contents were similar for both sets
of the ashes' specimens. The main concentrations
referred to are SiO 2 and Al 2 O 3 , while
Na 2 O, K 2 O, FeO, CaO and MgO were found in
small quantities. No significant amounts of Arsenic
were found.
Figures 4 and 5 present XRD patterns acquired
from the first and the second eruptions' typical
ash specimens, respectively. Reflections of SiO 2 ,
Al 2 O 3, K 2 O and Na 2 O confirm the presence of
the phases that were found using EDS.
Figure 5. x-ray diffraction of second eruption ash.
References
[1] J Horwell, C.J., Michnowicz, S., Le Blond,
J., 2008. Report on the mineralogical and geochemical
characterisation of Chaitén ash for the
assessment of respiratory health hazard. International
Volcanic Health Hazard Network(IVHNN)
report(available from
www.ivhhn.org).
[2] Watt, S.F.L.; et al., (2009). Fallout and distribution
of volcanic ash over Argentina following
the May 2008 explosive eruption of Chaiten,
Chile. 114. Journal of Geophysical Research.
101 Valparaíso, Chile