Metamorphic Petrology

Question 1

secondary rocks formed from pre-existing
igneous, sedimentary, and/or prior metamorphic rocks, which are
subjected to physicochemical conditions (P, T, and chemical active
fluids) higher than that at the earth’s surface.

Answer 1

metamorphic rock

Question 2

metamorphic rocks undergo partial
melting and a hybrid rock between igneous and metamorphic, known as ____________, could form

Answer 2

migmatites

Question 3

type of plate boundary between the Philippine plate and the Pacific plate

Answer 3

oceanic-oceanic convergence boundary

Question 3

the study of the subsolid
changes that a rock undergoes when exposed to
physicochemical conditions different from those
prevailing near the surface of the Earth.

Answer 3

metamorphic petrology

Question 4

defined by
characteristic mineral assemblages specific
to particular bulk-rock compositions

Answer 4

metamorphic facies

Question 5

types of metamorphism

Answer 5

contact and regional metamorphism

Question 6

high T, low P metamorphism

Answer 6

contact metamorphism

Question 7

high T, can be high P metamorphism

Answer 7

regional metamorphism

Question 7

types of deformation in metamorphic rocks

Answer 7

lineation and foliation

Question 7

refer to the transformation of
minerals into new mineral phases that are stable under the new metamorphic conditions

Answer 7

phase change

Question 8

deformation at any linear fabric elements

Answer 8

lineation

Question 9

deformation at any planar fabric element

Answer 9

foliation

Question 10

the property of a rock to split along a regular
set of sub-parallel, closely-spaced planes
– A more general concept adopted by some geologists is to consider this to be any type of foliation in which the aligned platy phyllosilicates are too fine grained to see
individually with the unaided eye
- secondary foliation related to fine grained rocks

Answer 10

cleavage

Question 11

A preferred orientation of inequant mineral grains or grain aggregates produced by metamorphic processes
– Aligned minerals are coarse grained enough to see with the unaided eye
– The orientation is generally planar, but linear orientations are not excluded
– Secondary foliation associated with coarser grained rocks

Answer 11

schistosity

Question 12

means that a metamorphic rock has one or
more metamorphic minerals that grew much larger than the
others.

Answer 12

porphyroblastic

Question 12

Either a poorly-developed schistosity or segregated into layers by metamorphic processes

Answer 12

gneissose structure

Question 12

a metamorphic rock composed
predominantly of calcite or dolomite. The protolith is
typically limestone or dolostone

Answer 12

marble

Question 12

a metamorphic rock composed
predominantly of quartz. The protolith is typically sandstone.

Answer 12

quartzite

Question 12

a comprehensive term for any isotropic rock (a
rock with no preferred orientation)

Answer 12

granofels

Question 13

a contact metamorphosed and silica
metasomatized carbonate rock containing calc-silicate minerals, such as grossular, epidote,
tremolite, vesuvianite, etc. Tactite is a synonym

Answer 13

skarn

Question 13

a type of granofels that is typically very fine-grained and compact, and occurs in contact aureoles.
these are tough, and tend to splinter when broken

Answer 13

hornfels

Question 14

a high grade rock of pelitic, mafic, or
quartzo-feldspathic parentage that is predominantly composed of OH-free minerals. Muscovite is absent and plagioclase and orthopyroxene are common.

Answer 14

granulite

Question 14

: a low-grade metamorphic rock that
typically contains chlorite, actinolite, epidote, and albite. Note that the first three minerals are green, which imparts the color to the rock. Such a rock is called _________ if foliated, and
___________ if not. The protolith is either a mafic igneous rock or graywacke

Answer 14

greenschist/greenstone

Question 15

a metamorphic rock dominated by hornblende + plagioclase. May be foliated or non-foliated. The protolith is either a mafic igneous rock or graywacke

Answer 15

amphibolite

Question 16

an ultramafic rock metamorphosed at low grade, so
that it contains mostly serpentine

Answer 16

serpentinite

Question 16

: a blue amphibole-bearing metamorphosed mafic
igneous rock or mafic graywacke. This term is so commonly applied
to such rocks that it is even applied to non-schistose rocks.

Answer 16

blueschist

Question 16

a green and red metamorphic rock that contains
clinopyroxene and garnet (omphacite + pyrope). The protolith is typically basaltic

Answer 16

eclogite

Question 16

Low temperatures and pressures relative to higher-grade metamorphism. Typically includes minerals like chlorite,
muscovite, biotite

Answer 16

low-grade metamorphism

Question 17

Moderate temperatures and pressures between
low-grade and high-grade metamorphism.
Common minerals include biotite, garnet, staurolite, andalusite, and in some cases, amphibole.

Answer 17

medium-grade metamorphism

Question 18

High temperatures and pressures, often associated with deep burial or tectonic processes such as mountain-building (orogeny).
Includes minerals like garnet, kyanite, sillimanite, staurolite, and sometimes orthopyroxene

Answer 18

high-grade metamorphism