Advertisements
Advertisements
Question
How are sedimentary rocks classified on the basis of their formation?
Advertisements
Solution
There are three types of this type of rocks :
- Mechanically formed rocks : Denudation of rocks by agents of change results in layers of sedimentary rocks by mechanism.
- Chemically formed rocks : These are formed by evaporation of calcarious water and accumulated along lake and lagoon beds, e.g. gypsum and rock salt.
- Organically formed rocks : These are formed by deposition of dead plants and animals e.g. limestone rock (or Calcareous rock) lignite, bituminous and anthracite coal are carbonaceous rocks formed by compression of vegetation under the layers of sedimentary rocks. In the same way petroleum in between the sedimentary rocks is the result of zurasic age dinosaurs e.g. shale rock, containing oil.
RELATED QUESTIONS
Differentiate between SIAL and SIMA.
How are rocks different from minerals?
With the help of your teacher, collect different types of rocks such as granite, sandstone, limestone, marble, slate, graphite, etc. and prepare a chart containing information about their colour, hardness, texture, and permeability.
Name two important landforms made by Igneous Rocks.
Which rocks are associated with fossil fuels?
State the types of rocks for the formation of which the following process is involved.
Formation of large crystals, coarse texture and slow cooling and compaction.
How are sedimentary rocks formed?
State the chief characteristics of metamorphic rocks.
Give one term for the following statement:
It has a definite chemical composition with its own chemical and physical properties.
Give reasons for the following
Extrusive rocks generally have small crystals.
Give reasons for the following
Silicates are the most common rock forming minerals.
Give reasons for the following
Rocks are of great economic significance.
Igneous rocks are found in the regions of volcanoes.
Parent Rock is converted to loose Rock by ______.
Statement (1): Sedimentary rocks consist of many layers.
Statement (2): Sedimentary rocks are formed by the sediments deposited at different points of time.
Match the following:
| Group 'A' | Group 'B' | ||
| A. | Granite | 1. | Bedrock |
| B. | Soil layer | 2. | Plutonic rock |
| C. | Barren island | 3. | Strip farming |
| D. | Soil conservation | 4. | Active Volcano |
Match the following.
| Group A | Group B | ||
| A. | Basalt | 1. | Anthracite |
| B. | Limestone | 2. | Extrusive igneous |
| C. | Coal | 3. | Metamorphic rock |
| D. | Gneiss | 4. | Sedimentary rock |
Match the following.
| A. | Granite | 1. | Bed rock |
| B. | Soil layer | 2. | Plutonic rock |
| C. |
Barren island |
3. | Strip farming |
| D. | Soil conservation | 4. | Active Volcano |
Statement (1): Sedimentary rocks consist of many layers.
Statement (2): Sedimentary rocks are formed by the sediments deposited at different points of time.
Statement (1): Sedimentary rocks consist of many layers.
Statement (2): Sedimentary rocks are formed by the sediments deposited at different points of time.
