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The following are the  hazardous effects of earthquake
i. They cause loss of human life due to collapse of buildings.

ii. Transport is affected due to disruption of railway and road systems.

iii. Infrastructure like buildings, dams and bridges develop cracks due to earthquakes.

iv. Earthquakes have economic effects like setback in trade and agriculture. Assets like houses and other buildings are also destroyed.

v. Problems arise due to shortage of electricity. At the same time, underlying cables are disturbed leading to disruption of communication systems.

vi. It becomes difficult to meet basic necessities of people like food and water.

vii. Water shortage also leads to rise of epidemics due to lack of proper sanitation.

The causes of plate movement are:

1. Thermal Convection: A. Holmes proposed that the sub-crustal convection currents invoke the mechanism of thermal convection. It acts as a driving force for the movement of plates.
2. Movement of Currents: Hot currents rise and then cool as they reach the surface. At the same time, cool currents sink down. The convectional movement moves the crustal plate.
3. Floating of Plates: The rigid plates of the lithosphere which floats on more mobile asthenosphere are in constant motion.
4. Hot Spots of Volcanic Activity: Small currents of past volcanic activity are often located far from any active plate boundary suggesting the effect of convection currents on the lithosphere. These are called the Hot Spots.
5. Volcanic Eruptions: The source of magma in the mantle remains fixed in position while the lithospheric plate above it moves steadily. In this way, volcanoes are formed over a hot spot but they become extinct. These extinct volcanic form a chain that is a record of plate motion.

oblate spheroid

"Geography is split into two main areas that make it easier to wrap your head around: Physical geography looks at the natural processes of the Earth, such as climate and plate tectonics. Human geography looks at the impact and behaviour of people and how they relate tothe physical world."

There is a great importance of India in the eastern world. It lies between West Asia and East Asia. The trans-oceanic routes connecting Africa, Europe, West Asia and South-East Asian countries pass through India. Sea has played an important role in India’s external relations particularly with West Asia and East Africa. The Indian and the Chinese cultures meet in Southeast Asia and they together mingle with local cultures to give rise to a new synthesis reflected in terms like Indo-China.

Following are the four dimensions of geographical study or simply geography, 

1-Regional Geography

2-Quantitative Revolution 

3-Environmental determinism

4-Critical Geography

Explanation:

1- Regional Revolution: This is the part in which there are discussions upon, how the world regional geography works, the description of the areas, how international trends work about in the world, what differentiation exists among various regions. 

2-Quantitative Revolution: 

These are the spatial dimensions which include mapping, movement and transportation, what is the distribution of areas, and spatial patterns, what are the boundaries along with what population is located where. This all is recorded through computerized systems. 

3-Environmental determinism: This takes a look at how human beings impact nature and the world and vice versa. This study looks at natural disasters, environmentalism, the environmental perception, etc. 

4-Critical Geography

It looks at the effects and how humanity has the potential to transform the environment

Geography as an integrated discipline because Geography is all about nature and environment. It covers whole physical areas in the planet, and holistic nature. 

Geography connects people with nature or environment. People can know about general knowledges from Geography. It connects people with the world. Earth, sky, lands you can know anything about world from Geography.

According to Wegener, all the continents formed a single continental mass, a mega ocean surrounded by the same. The super-continent was named Pangaea, which meant all earth.

Pangaea or Pangea was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It assembled from earlier continental units approximately 335 million years ago, and it began to break apart about 175 million years ago.In contrast to the present Earth and its distribution of continental mass, much of Pangaea was in the southern hemisphere and surrounded by a superocean, Panthalassa. Pangaea was the most recent supercontinent to have existed and the first to be reconstructed by geologists.

Body waves are the waves that can travel through the layers of the earth. They are the fastest waves and as a result, the first waves that seismographs can record. Body waves can move through all states of matter including rocks and molten lava.