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Aphanites (adj.
aphanitic; from
Ancient Gr**** αφανης (aphanḗs) 'invisible') are
igneous rocks that are so fine-grained that
their component mineral crystals...
- high in
silica and low in
alkali metal oxides. It has a fine-grained (
aphanitic) to
porphyritic texture and is
intermediate in
composition between andesite...
- silica-rich of
volcanic rocks. It is
generally gl****y or fine-grained (
aphanitic) in texture, but may be porphyritic,
containing larger mineral crystals...
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Felsite is a
petrologic field term used to
refer to very fine-grained or
aphanitic, light-colored
volcanic rocks which might be
later reclassified after...
- bomb
Lapilli Volcanic ash
Volcanic rocks are
usually fine-grained or
aphanitic to gl**** in texture. They
often contain clasts of
other rocks and phenocrysts...
- rock
composed mostly of
alkali feldspar. It is
usually light-colored and
aphanitic (fine-grained), with
minor amounts of
mafic minerals, and is
formed by...
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Basalt (UK: /ˈbæsɔːlt, -əlt/; US: /bəˈsɔːlt, ˈbeɪsɔːlt/) is an
aphanitic (fine-grained)
extrusive igneous rock
formed from the
rapid cooling of low-viscosity...
- main
types of
textures are phaneritic,
aphanitic, porphyritic, gl****y, pyroclastic, and pegmatitic.
Aphanitic (a = not,
phaner = visible) rocks, in contrast...
-
distinguished with the
unaided human eye. In contrast, the
crystals in an
aphanitic rock are too fine-grained to be identifiable.
Phaneritic texture forms...
-
volcanic eruptions,
rapidly solidifies.
Hence such
rocks are fine-grained (
aphanitic) or even gl****y.
Basalt is the most
common extrusive igneous rock and...
