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Porphyry (/ˈpɔːrfəri/ POR-fə-ree) is any of
various granites or
igneous rocks with co****-grained
crystals such as
feldspar or
quartz dis****d in a fine-grained...
- are
mostly very-co**** grained,
ranging in type from
microgranites to
porphyroid granites. The m****if is
tilted in a north-westerly
direction and was cut...
- and
geochemistry of the
pyroclastics of the
Lower Ems/Lower
Devonian (
porphyroids) in the
southern Rhenish Slate Mountains. (=
Geological treatises Hessen...
- thick, made up of
quartz porphyroids and tuff,
mainly in the west (Hohe Salve,
Hahnenkamm and Wildseeloder). Over the
porphyroids lie
various horizontal...
- bottom): Génis
greenschist Génis
sericite schist Puy-de-Cornut
arkose Génis
porphyroid The Génis
greenschist is the
youngest formation of the Génis Unit. The...
- type
foothills Type of rock Tri****ic carbonate, quartzite/quartz conglomerate,
arkose slate-breccia-
porphyroid-series (Wechsel slate,
Alpine verrucano)...
- developed. One
common form of
aggrading neomorphism is
called porphyroid neomorphism.
Porphyroid neomorphism occurs when a
small number of
large crystals form...
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igneous origin for the rock. Such porphyry-schists have been
called porphyroids or
porphyroid-schists, and in the
United States the name
aporhyolite has been...
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Proterozoic rocks are
better defined and
include phyllite, schist, quartzite,
porphyroids, porphyritoids,
marble and jaspellite,
intruded by 1.8 billion year old...
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possible affinity to the
Ordovician Grès
armoricain from
Brittany Génis
Porphyroids,
metaignimbrites from the Cambrian/Ordovician
boundary Excideuil Sericite...
