Dynamic metamorphism is caused by high temperature.

Sedimentary rocks are the hardest ones.

Soils are classified on the basis of their formation colour, physical and chemical properties. Soil is classified into six major types. They are
1. Alluvial soil
2. Black soil
3. Red soil
4. Laterite soil
5. Mountain soil
6. Desert soil

1. The rocks are the solid mineral materials forming a part of the surface of the earth and other similar planets.
2. The earth's crust is composed of rocks.
3. A rock is an aggregate of one or more minerals.
4. Rock is an important natural resource and is found in solid state.
5. It may be hard or soft in nature.
6. They may occur either in the form of elements or compounds.

Classification of soils:
Soils are classified on the basis of their formation; colour, physical and chemical properties. Soil is classified into six types.
1. Alluvial soil:
(i) These soils are found in the regions of river valleys, food plains and coastal regions.
(ii) It is the most productive of all the soils. Suitable for cultivation of sugarcane, jute, rice, wheat and other food crops.
2. Black soils:
Formed by withering of igneous rocks: Black soil is clay in nature. it is retentive of moisture. It is ideal for growing cotton .
3. Red soils:
(i) Formed by weathering of metamorphic and crystalline rocks.
(ii) The presence of iron oxide makes this soil brown to red in colour.
(iii) Found in semi-arid regions. It is. not a fertile soil. It is suitable for millet cultivation.
4. Mountain soils:
(i) Found over the slopes of mountains.
(ii) Soils in these regions are thin and acidic.
(iii) However characteristic of soil differs from region to region based on the altitude.
5. Desert soils:
These are sandy soil found in the hot desert regions.
(i) These soils are porous and saline.
(ii) Since it is infertile, agriculture in these soils is not so successful.