-
common members of the
feldspar group are the
plagioclase (sodium-calcium)
feldspars and the
alkali (pot****ium-sodium)
feldspars.
Feldspars make up
about 60%...
-
anorthoclase (a type of
feldspar)
found in the
immediate area
surrounding Mount Erebus near
McMurdo Station, Antarctica. This type of
feldspar is rich in sodium...
- Trinitite, also
known as
atomsite or
Alamogordo gl****, is the
gl****y residue left on the
desert floor after the plutonium-based
Trinity nuclear bomb test...
-
Oligoclase is a rock-forming
mineral belonging to the
plagioclase feldspars. In
chemical composition and in its
crystallographic and
physical characters...
-
where plagioclase-group
feldspar is
oligoclase Tuff – Rock
consolidated from
volcanic ash Vitrophyre –
Gl****y volcanic rock -
Gl****y igneous rock with phenocrysts...
- əlaɪt/ RY-ə-lyte) is the most silica-rich of
volcanic rocks. It is
generally gl****y or fine-grained (aphanitic) in texture, but may be porphyritic, containing...
-
between andesite and rhyolite. It is
composed predominantly of
plagioclase feldspar and quartz.
Dacite is
relatively common,
occurring in many
tectonic settings...
-
poured out vast
floods of
black basalt,
containing feldspar, augite, olivine, and iron ores in a
black gl****y base. They are
highly liquid when discharged,...
-
spreading outwards through a fine
grained or
gl****y rock. In
variolites there are
straight or
feathery feldspar crystals (usually oligoclase)
forming pale-colored...
-
present in
spongy growths among the
feldspars of the groundm**** (as in the
trachyte of
Berkum on the Rhine).
Gl****y forms of
trachyte (obsidian) occur...
