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Showing posts from March 24, 2010

geography short notes -10

WADI
It is traditionally a valley. In some cases it can refer to a dry river bed that contain water only during times of heavy rain. The wadi is very widely found in arabic to ponyms were streams in a desert environment & generally are dry year round except after rain. The deposition of wadi is rapid because of the sudden loss of the velocity & absorption of the water into the ground.

Why was the Prime Meridian established at Greenwich

In 1675, the Royal Observatory at Greewich, outside of London was created to study the determination of longitude (a vital comonent to oceanic navigation). The United Kingdom and, by association, the United States, used Greenwich as the reference point for longitude.
Thus, by the time of an international conference in 1884 to establish fixed degrees of longitude on the planet, many countries had been using Greenwich as the Prime Meridian for decades so the tradition became internationally accepted



World Largest Coral Reef! GREAT BARRIER REEF - WORL…

geography short notes -9

STACK
It is a geological land form consisting of a steep & often vertical column / columns of rocks in the sea near coast.

Stacks are formed when a part of a headland is eroded leaving small island. They are also form when natural arch collapses due to sub-aerial processes & gravity.

A stack may collapse / be eroded leaving a stums. Stacks forms most commonly on chalk cliffs, beacause of the medium resistance to erosion.

Cliffs with weaker rock such as clay tend to stump & erode too quickly to form stacks, while harder rocks such as granite erode in different ways. stacks are often important sites for nesting seabird.

It is also famous for rock climbing.



States and Rivers

1.Rivers flowing into Bay of Bengal

* Karnaphuli River from Mizoram and Bangladesh
* Meghna River from India and Bangladesh
o Titas River in Tripura
+ Haora River in Agartala

Brahmaputra River Basin

* Brahmaputra River
o Lohit River
o Burhidihing River
o Dihing River
o Kameng River
o Manas River
o Sankosh

geography short notes -8

PLAGIOCLASE

it is very important series of tectosilicate minerals within the fields par family. rather than referring to a particular mineral with a specific chemical composition, plagioclase is a solid solution series, more properly known as plagioclase feldspar series from greek word "oblique fractor" in reference to its two cleverage angles. the series range from arbite to anorthite endmembers where sodium & calcium atoms can substitue for each other in the mineral crystal lattice structure. plagioclase is a hand samples is often by its polysynthetic twinning or 'record-froove' effect. plagioclase is major constituent mineral in earth's crust. & is consequently an important diagnostic tool in petrology for identifying composition, origin & evolution of igneous rocks.

PLAGIOCLASE MINERALS & THEIR COMPOSITIONS
NAME = %NaAlSi3O8(%Ab) = % CaAl2Si2O8(%An)

- albite = 100-90 = 0-10

- oligoclase = 90-70 = 10-30

- andesine = 70-50 = 30-50

- labradorite …

geography short notes -7

Names of Tropical Cyclones

North Atlantic & North Pacific - Hurricane
Western North Pacific - Typhoons
Australia - Wily Wily
Indian Ocean - Cyclones
Phillipine Islands - Baguio
Japan - Nowaki ( in olden days)
Taifu (Recent Name)
Rest of the World - Tropical Cyclone

National Parks in India Bandhavgarh National Park This park is some of the left out preserved wild pockets of Madhya Pradesh of what were once splendid forests that extended across the whole of Central India.
Ranthambore national Park A nearby attraction of Sawai Madhopur, in the state of Rajasthan, Ranthambore National Park is an outstanding example of Project Tiger's efforts at conservation in the India.
Kaziranga National Park Assam The land of Rhino is counted among the two major wild pockets, the only surviving habitats of this prehistoric survivor in India.
Kanha National Park In the state of Madhya Pardesh,this place is called a wild hideout taken straight from the famous "Jungle Book".
Sundarbans National Par…

geography short notes -7

KYANITE

the name derived from the greek word kyanos, meaning blue. it is typicaly blue siliacte mineral, comonly found in aluminium-rich metamorphic pegmatites & sedimentary rocks. it is strongly anisotrophic , in that its hardness varies depending on its crystallographic direction. this is used primarily in refractory & ceramic products, including porcelain plumbing fixtures & dinnerware. it is also used in electrical insulators & abrasives. it undergoea an irreverssible expansion when fired at high temperature. this is also been used as gemstone.

ASSOCIATED MINERALS OF KYANITE :
andalusite Ai2SiO5
sillimanite Al2SiO5
Quertz SiO2
staurolite Fe2Al9Si4Onn(OH)2
micas AB2-3(X1Si)4 O10(O, F, OH)2
garnete A3B2(SiO4)3


LAHAR

it is a type of mudflow composed of pyroclastic material & water that flows down from a volcano, typically along a river valley, the term lahar originated in the Javanese language of Indonesia. lahars have the consistency of concrete. fluid where moving …

geography short notes -6

India India
IntroductionIndiaBackground: The Indus Valley civilization, one of the oldest in the world, dates back at least 5,000 years. Aryan tribes from the northwest invaded about 1500 B.C.; their merger with the earlier Dravidian inhabitants created the classical Indian culture. Arab incursions starting in the 8th century and Turkish in the 12th were followed by those of European traders, beginning in the late 15th century. By the 19th century, Britain had assumed political control of virtually all Indian lands. Indian armed forces in the British army played a vital role in both World Wars. Nonviolent resistance to British colonialism led by Mohandas GANDHI and Jawaharlal NEHRU brought independence in 1947. The subcontinent was divided into the secular state of India and the smaller Muslim state of Pakistan. A third war between the two countries in 1971 resulted in East Pakistan becoming the separate nation of Bangladesh. Despite impressive gains in economic investment and output, In…