Foliation is a common texture in many metamorphic rocks. What is foliation? the
ID: 118129 • Letter: F
Question
Foliation is a common texture in many metamorphic rocks. What is foliation?
the compaction and resultant decrease in volume of a rock during metamorphism
the transformation of unstable minerals into stable forms during metamorphism
the preferred allignment of elongate or platy minerals, or the banding of mafic and felsic minerals
the removal of all fine-grained minerals from a rock during intense metamorphism
a.the compaction and resultant decrease in volume of a rock during metamorphism
b.the transformation of unstable minerals into stable forms during metamorphism
c.the preferred allignment of elongate or platy minerals, or the banding of mafic and felsic minerals
d.the removal of all fine-grained minerals from a rock during intense metamorphism
Explanation / Answer
Foliation is caused by shearing forces (pressures pushing different sections of the rock in different directions), or differential pressure (higher pressure from one direction than in others). The layers form parallel to the direction of the shear, or perpendicular to the direction of higher pressure.foliation is any penetrative planar fabric present in metamorphic rocks.
Examples include the bands in gneiss(gneissic banding), a preferred orientation of planar large mica flakes in schist (Schistocity), the preferred orientation of small mica flakes in phyllite.
The answer is option c.