Ch 7. Minerals and Rocks Flashcards
What is a mineral ?
Mineral is an inorganic element naturally occuring with an ordered atomic structure, definite chemical composition and physical properties
What is the study of minerals called ?
Mineralogy
What are six major mineral groups ?
Feldspar, Quartz, Pyroxene, Amphibole, Mica and Olivine
What are some examples of organic minerals ?
Natural gas, petroleum and coal
What are the major elements of the Earth’s crust by weight ?
Oxygen, Silicon, Aluminium, Iron, Calcium, Sodium, Potassium and Magnesium (in decreasing order)
What is a cleavage in minerals?
The tendency of a mineral to break in specific directions to create relatively flat surfaces
What is a fracture in minerals ?
The crystal can split in an irregular way, not along cleavage planes
What is lustre in minerals ?
Appearance of a material regardless of color ex: metallic, silky, glossy, etc
What is a streak in minerals ?
The color of a mineral’s powder
What is a sclerometer ?
It measures the absolute hardness of minerals.
Which ten minerals are used to measure the degree of hardness ?
Talc, Gypsum, Calcite, Fluorite, Apatite, Fledspar, Quartz, Topaz, Corundum and Diamond
Which major elements are found in Feldspar ?
Silicon and Oxygen
What are the common uses of Feldspar ?
Glass making and Ceramics
What are the major elements of Olivine ?
Magnesium, Iron and Silica (MIS)
What is the major source of Olivine
Mafic Igneous rock
What is the common use of Olivine ?
Most commonly used in jewellery
Quartz is mainly found in ?
Granite and Sand
What is the major element of Quartz ?
Silica
What are the main uses of Quartz ?
Mainly used in the manufacturing of radio, radar, etc
Which elements are found in Pyroxene ?
Aluminium, Calcium, Magnesium, Silicon and Iron (MACIS)
Which mineral is commonly found in meteorites ?
Pyroxene
Which major elements are found in Amphibole ?
Magnesium, Aluminium, Calcium, Iron and Silicon (MACIS)
What is the common use of Amphibole ?
Commonly used in the Asbestos industries
What is Hornblende ?
Another form of Amphiboles
Which elements constitute Mica ?
Magnesium, Aluminium, Potassium, Iron and Silicon
Mica is widely used in ?
Electronic instruments
What are different types of minerals ?
Metallic minerals - Ferrous, Non ferrous, Precious
Non metallic minerals
Energy minerals
What is a rock ?
A rock is an aggregate or physical mixture of many minerals
Name the common minerals that are found in many rocks
Quartz and Feldspar
What is Petrology ?
Study of rocks
What are the different types of rocks based on the mode of formation ?
Igneous rocks, Sedimentary rocks, Metamorphic rocks
How are Igneous rocks formed ?
The cooling of extremely fluid and hot liquid magma forms Igneous rocks
What type of rocks are also called as Primary rocks ?
Igneous rocks
What are Intrusive Igneous rocks ?
These are formed when magma cools and solidifies below the earth’s surface
What are Plutonic rocks ?
Deep seated intrusive igneous rocks are called Plutonic rocks
What are Hypabyssal rocks ? Give some examples
Shallow depth intrusive igneous rocks are called Hypabyssal rocks. Ex: Granite, Dolerite
What are Extrusive Igneous rocks ? Give two examples
These are formed on the earth’s surface by the cooling of the lava. Ex: Bassalt, Gabbro
What type of rocks are called as Volcanic rocks ?
Extrusive igneous rocks
What is Lithification ?
The process of successive deposition and formation of sedimentary rocks
Which rocks are called as Stratified rocks ?
Sedimentary rocks
What are the different types of sedimentary rocks (based on mode of formation) ?
- Mechanically formed / Classic sedimentary rocks
- Organically / Biologically formed sedimentary rocks
- Chemically formed sedimentary rocks
Give few examples of mechanically formed sedimentary rocks
Conglomerate, Braccia, Sandstone and Shale
Name few organically formed sedimentary rocks
Coal, limestone, chalk and chert
Mention few chemically formed sedimentary rocks
Halite, Potash and Limestone
How are metamorphic rocks formed ?
They are formed under the action of temperature, volume changes and pressure on original form of rocks. It is the process of recrystallization and reorganisation of materials within the original rocks
What is Dynamic metamorphism ?
When metamorphism occurs without any major chemical alterations, it is referred to as dynamic metamorphism
What is Thermal metamorphism ?
If the impact of heat induces metamorphism, it is referred to as Thermal metamorphism
What is Contact metamorphism ?
If the reorganisation of a rock happens when it comes in direct contact with the hot magma, it is called as contact metamorphism
What is Regional metamorphism ?
If the rocks are metamorphosed due to tremendous heat or pressure and formed due to tectonic shearing, it is called as regional metamorphism
What are Foliated and Non-Foliated metamorphic rocks ?
On the basis of presence or absence of bands of mineral grains metamorphic rocks can be classified into Foliated and Non-Foliated metamorphic rocks
Give some examples of Foliated and Non-Foliated metamorphic rocks ?
Foliated - Gneiss, Slate, Schist
Non-Foliated - Marble, Quarzite
What is a Rock Cycle ?
Rocks do not remain in their original form for a long time, but can undergo transformation. This continuous process by which old rocks are turned into new ones is called Rock Cycle
