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Valencia” is a
chondrite (silicate-rich stony meteorite) and
forms part of the rock collection of the
Department of Geology of the University of
Valencia, Spain. References do exist regarding
falls on Spain’s east coast: Oliva-Gandía in 1520,
Valencia in 1603, and Peñíscola in 1916.
Unfortunately, no specimens are known to exist.
Thus, the meteorite Valencia cannot be clearly
assigned to a specific event.
Valencia is a parallelepiped-shaped specimen
measuring 37 by 24.5 by 19.5 centimeters, weighing
33.5 kilograms, and having an average density of
3.7 grams per cubic centimeter. Externally, it
displays a 1-millimeter-thick, dark-fusion crust
and numerous imprints of atmospheric flight
(regmaglypts and friction striae).
Transmitted and reflected light microscopy and
X-ray diffraction studies, as well as electron
microprobe analyses, indicate that Valencia is
composed of silicates (forsterite, clinoenstatite,
and minor albite), iron-nickel alloys (kamacite,
taenite), sulphides (troilite), oxides (periclase,
hercynite) and sulphates (yavapaiite).
Geochemically, Valencia matches the ordinary
H5-type chondrite.
Estimated exposition ages for Valencia, based
on isotopes of helium, neon, and argon, indicate
an average exposition age of 6.9 Ma, with a
possible loss of helium. Ages of gas retention,
based on isotopes of helium and argon, suggest
that the loss of helium was greater than that of
argon. Researchers are still investigating whether
this loss was conditioned by a subsequent impact,
after the individualization impact of Valencia
from the parent body, or resulted from other
processes.
From
Muñoz-Sanz et al.
(1999) |
Muñoz Sanz J. (1997) Caracterizacion
petrológica y geoquímica del meteorito "Valenciano".
Graduation thesis, Universidad Complutense, Madrid,
Spain. 96 p.
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