Engineering Geology Assessment Questions and Answers on “Structures of Metamorphic Rocks – 02”.
1. What are the rocks showing granulose structure called?
a) Granolites
b) Granulites
c) Granilites
d) Granites
Answer: b
Clarification: The individual grains may be irregular in outline but are interlocking. Foliation is absent or negligible. Rocks with granular structure are termed as granulites.
2. The cleavage also called slaty cleavage is __________
a) Flow cleavage
b) Fracture cleavage
c) Fine cleavage
d) Medium cleavage
Answer: a
Clarification: Flow cleavage is also called flow cleavage because of its development in slates. This cleavage is developed during metamorphism by parallel arrangement of highly cleavable flaky and platy minerals.
3. The cleavage involving microfractures is __________
a) Flow cleavage
b) Fracture cleavage
c) Fine cleavage
d) Medium cleavage
Answer: b
Clarification: Fracture cleavage is developed due to parallel orientation of very fine structures, often called microfractures, that may be developed in minerals of a rock undergoing dynamic metamorphism.
4. It is easy to distinguish two types of cleavages in hand specimen.
a) True
b) False
Answer: b
Clarification: It is often difficult to distinguish between two types of cleavage in hand specimen. The cleavage structure is of great importance in field mapping of metamorphic rocks as it provides very useful information about structural feature like folding.
5. Slaty cleavage is result of which metamorphism of clays and shales?
a) Thermal
b) Dynamic
c) Thermodynamic
d) Barometric
Answer: b
Clarification: Traces of bedding planes may be found as relict structures in some slates. The slaty cleavage is the result of severe type of dynamic metamorphism of clays and shales.
6. Schistose is resulted due to __________
a) Recrystallization
b) Reforming
c) Reorientation
d) Recrystallization and reorientation
Answer: d
Clarification: Schistose results due to combines effect of heat and pressure during metamorphism involving both recrystallization and reorientation of platy minerals as irregular layers or bands.
7. The term including both cleavage and schistosity is __________
a) Foliation
b) Fracture
c) Parting
d) Reverbrance
Answer: a
Clarification: Foliation is a broader term explaining layered structure in metamorphic rocks and is often understood to include cleavage and schistosity. However, foliation in particular expresses segregation of minerals in an alternating manner.
8. Foliation generally results due to which metamorphism?
a) Dynamic
b) Thermal
c) Thermodynamic
d) Barometric
Answer: c
Clarification: Foliation generally results due to thermodynamic metamorphism in coarse-grained igneous rocks like granites and sandstones and metamorphic rocks like schists.
Engineering Geology Assessment Questions,