Module 4, 5, 6 Flashcards
(51 cards)
These are igneous rocks formed at considerable depths generally between 7-10 km below the surface of the Earth.
Plutonic Rocks
These are rocks that have been formed from an originally hot molten material through the process of cooling and crystallization.
Igneous Rock
These are the important conditions for the original material to form igneous rocks, except?
Hot Surrounding
Options: B. Hot Surrounding, C. Molten state, D. None of these
Igneous rocks through intrusive formation are formed from?
Magma
Options: A. Magma, B. Lava, C. Both A & B, D. None of these
This term is used for the textures in which the minerals are perceivably crystallized but in extremely fine grain.
Microcrystalline
These are also termed phaneric.
Holocrystalline
It is when minerals are crystallized and others are of glassy character in the same rock.
Merocrystalline
It is when most of the crystals are of anhedral or irregular shapes.
Allotriomorphic
It is when all the component minerals are of approximately equal dimensions.
Equigranular
It is when the rock is micro granular, the grains being mostly microscopic crystals but these invariably show perfect outlines.
Felsitic texture
Because of its very slow rate of cooling, the rocks resulting are coarse grained.
Plutonic Rocks
These are the igneous rocks formed on the surface of the Earth by cooling and crystallization of lava erupted from volcanoes.
Volcanic Rocks
These rocks get exposed on the surface of the Earth as a consequence of erosion of the overlying strata.
Plutonic Rocks
The grain size of the crystals formed in these rocks is very fine, often microscopic.
Volcanic Rocks
It is defined as the mutual relationship of different mineralogical constituents in a rock.
Texture
It is when all the constituent minerals are distinctly crystallized.
Holocrystalline
These igneous rocks are formed at intermediate depths, generally up to 2 km below the surface of the Earth.
Hypabyssal Rocks
Options: A. Volcanic Rocks, B. Plutonic Rocks, C. Hypabyssal Rocks
It is when some minerals in the rock are exceptionally larger or smaller than the other.
Inequigranular
Options: A. Equigranular, B. Orthogranular, C. Inequigranular
It is when majority of the components are in fully developed shapes.
Panidiomorphic
Options: A. Panidiomorphic, B. Hypidiomorphic, C. Allotriomorphic
These are formed when the magma being injected is considerably viscous so that it is unable to flow and spread for greater distances.
Laccoliths
Options: A. Sills, B. Phacoliths, C. Laccoliths, D. Lopoliths
It is when the constituents are very fine in size and glassy or non-crystalline in nature.
Holohyaline
Options: A. Holocrystalline, B. Holohyaline, C. Merocrystalline
Defined as plutonic light-colored igneous rocks.
Granite
Options: A. Granite, B. Diorite, C. Andesite, D. Syenites
It is when the rock contains crystals of all categories: euhedral, subhedral or anhedral.
Hypidiomorphic
Options: A. Panidiomorphic, B. Hypidiomorphic, C. Allotriomorphic
These exhibit perfect or semi perfect parallelism of crystals or crystallites in the direction of the flow of magma.
Directive texture
Options: A. Directive texture, B. Trachytic texture, C. Trachytoid texture