- A
porphyroblast is a
large mineral crystal in a
metamorphic rock
which has
grown within the
finer grained matrix.
Porphyroblasts are
commonly euhedral...
- off from
either side of the
porphyroblast within the
strain shadows.[citation needed]
During shearing, the
porphyroblast may rotate, to form a characteristic...
-
forms a re-entrant as it is
absorbed by the
growth of the
andalusite porphyroblast. The
cycle of growth-****ation-growth then
repeats itself, creating...
-
followed by
exhumation (uplift). The
porphyroblast of
garnet was
formed during high
grade metamorphism while the
porphyroblast of
cordierite was
formed during...
- A
poikiloblast is a
porphyroblast mineral with
small inclusions of the
previous rock in it. From the
texture (if any)
shown in the inclusion, the deformation...
-
characterized by co****,
irregular grains,
including some
larger grains (
porphyroblasts.)
Sandstone has been used
since prehistoric times for construction,...
- may have been
phenocrysts or
porphyroblasts in the
original rock.
Porphyroclasts are
often confused with
porphyroblasts. The
latter are also
large crystals...
- marble,
charnockites and
other non-foliated
metamorphic rocks without porphyroblasts.
Characteristics defining granoblastic texture include:
grains visible...
-
metamorphic rock
characterized by an
abundance of
platy minerals. In this example, the rock has
prominent sillimanite porphyroblasts as
large as 3 cm (1.2 in)....
- megaphenocrysts. In
metamorphic rocks,
crystals similar to
phenocrysts are
called porphyroblasts.
Phenocrysts are more
often found in the
lighter (higher silica) igneous...
