1.GEOMORPHOLOGY

Geomorphology

This chapter can be divided as three parts for the purpose of convenience:

Part 1:
Origin and evolution of the earth's crust; 
Fundamentals of geomagnetism; 
Physical conditions of the earth's interior; 
Geosynclines; 
Continental drift; 
Isostasy; 
Plate tectonics; 
Recent views on mountain building; 
Vulcanicity; Earthquakes and Tsunamis; 

Part 2:
Factors controlling landform development; 
endogenetic and exogenetic forces; 
Concepts of geomorphic cycles and Landscape development ; 
Denudation chronology; 
Channel morphology; 
Erosion surfaces; 
Slope development ; 

Part 3:
Applied Geomorphology : Geohydrology, economic geology and environment.




VULCANITY

1.Fumaroles

what- Emission of gases +water vapour from vents

associated with volcanic erutions 

when-Takes place after volcanic eruption

why- due to cooling and contraction of magma after termination of eruption.

Fumaroles can be found along linear fracture or found along crater 

contents- gases- co2 , N,S,O2. Fumaroles dominated by S is called Solfatra 

example- Katmai volcano of Alaska- called a valley of ten thousand smokes

2.Geysers
Intermittent spouting of hot water and steam explosively from their craters.
Example- Old Faithful Geysers. Tellow stone national park USA, Iceland

3.Hotspring
A hot spring is a spring produced by the emergence of geothermally heated groundwater that rises from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth. While some of these springs contain water that is a safe temperature for bathing

Water issuing from a hot spring is heated geothermally, that is, with heat produced from the Earth's mantle. In general, the temperature of rocks within the earth increases with depth. The rate of temperature increase with depth is known as the geothermal gradient. If water percolates deeply enough into the crust, it will be heated as it comes into contact with hot rocks. The water from hot springs in non-volcanic areas is heated in this manner.

Q)Difference between Geyser and hotspring

5. Intrusive topography

Batholith- long iregular,dome shaped, deep within earth. ex- found in ranchi plateu as ranchi batholith
laccolith- intrusion between sedimentary layers.magma pushes the sedimentary layer of upper strata to arch up.
loppolith- into shallow concave basin
sills- thick beds between bedding planes of sedimentary layers
sheets- thin layers
dykes-perpendicular

6.Discuss extrusive topography
elevated forms- volcanic cones- cinder, composite, parasitic, acid, basic, lava plug, and lava domes
depressed forms- crater caldera

lava plateau and domes
lava plains

7.Crater
depression formed at the mouth of volcanic vent.
crater lake
craterlets- small sized crater witin extensive crater
adventive crater- in parasite cones

8.Caldera.
enlarged form of crater
two concept- 1.due to subsidence 2. due to violent eruption
nested or grouped caldera- smaller caldera housed in big caldera

9. World distribution of volcanoes
Circumpacific- erebus of antartica to mayon of philipines
Mid continental- etna, visuvious, stromboli
mid Atlantic-iceland ,azores and St.helena
Intra-plate- hawaai to kamchatk

10. Plate tectonics and vulcanity

That is a close relationship between plate boundaries and vulcanity

15%active at constructive player margin

80%at destructive plate boundary

Some intra plate -Hawaii, fault zone of east Africa

Plate boundaries and intensity of volcanic activity

1. Diverge divergent played boundaries associated with quite eruption that is fissure eruption the volcanic lava is tholeitte

2. Effective plate boundary in the circum Pacific associated with violent eruption they consist of aand andesite-dacite and rhyolite

3. Active plume - Hawai

Pelean type- Pelee volcano of Martinique island.Most violent and most explosive

Ejected lavas are most viscous and pasty

Great force and intensity and roaring noise

Visuvius-extremely violent expulsion of magma due to enormous volume of explosive gases

Fissure type-slow upwelling of magma and spread over ground surface. Example- Laki fissure eruption in Iceland