Where is Rice grown ?

Rice provides more food for more people than any other cereal crops in the world. Its is
The basic food crop in much of southern and eastern Asia.

Rice needs hot weather and plenty of water. The water may come from heavy rain, such as the monsoon rains of Asia, or from irrigation. Rice needs flat land, because the water level in the fields must be carefully controlled. Many hillsides in Asia are terraced to get
Enough flat land.

Where are Deserts being Created .?

On the edges of some of the Earths Natural deserts, the environment is being upset by poor farming methods and mismanagement.

Semi – Desert areas have fragile soils and difficult climates.Several good years are often followed by several bad years. In the good years, farmers may extend the cultivated areas, or increase their flocks and herds and dig more wells . But ina series of dry years,
Crops fail, animals exhaust the pasture , the bare soil is roded and many wells dry up. Such problems created the dust bowl in the USA in the 1930 and extended the Sahara in the 1970s.

What is Artesian Water ?

Artesian water is underground water which rises to the surface under natural pressure.The name comes from Artois in France, where many wells have been dug to reach artesian water in the underlying chalk.

Rain falling o higher land can flow through the layers of porous rocks. Beneath the low land, the porous rocks are sandwiched between impervious layers. The water bearing layer is called an aquifer .The Great Artesian Basin Of Australia is the worlds largest.

What are the most common Rock-Forming Minerals ?

The majority of minerals found in the rocks of the Earth’s Crust are silicates.

The Earth’s crust is made up of different kind of rocks. Most sedimentary rocks from accumulations of minerals which were weathered out of igneous rocks. Most of these minerals will be silicates.Silicates are a large group of minerals , all of which contains silica and oxygen. The commonest silicate family is feldspar.

What is COAL ?

Coal is a rock which is burned as fuel. It is called a ‘fossil fuel’ because it formed from the remain of trees and plants millions of years ago. Imprints of these plants can be found on some lumps of coal.

Coal is usually found in layers, called seams, of different thickness sandwiched between other rocks which formed at the same time. The oldest known coal seams are about 360 million years old .

What are oil and Natural Gas ?

Oil and natural gas are fossil fuels. They formed from the remains of tiny plants and animals which one lived in tropical seas. They were changed by chemical processes into gases and liquids.

Oil and gas collect in porous rocks, which allow liquids to soak through. They are trapped between impervious rocks, which will not allow liquids to pas through. Some oil wells pump oil froma huge area, but other tap only a small area and soon run dry.

Where is Monument Valley ?

Monument Valley is part of the Colorado Plateau, in the dry south – west of the USA.
The towers , columns and castle – like masses of rock shown in the photograph are completely natural monuments. They are mainly sandstones and other sedimentary rocks

What would happen if all the world ice melted ?

If all the ice in the world melted, new land would be revealed in the Artic and the Antarctica and in some mountain. But large area of the world would be flooded as sea – level rose .

Sea- level has changed in the past during glacials and inter – glacial , so it may change in that future. If the world’s ice melted, sea – level would rise by at least 65 metres, Denmark would be flooded, and many great capitals such as London, Dublin, Paris, Rome, and Helsinki would be drowned.

Where is the largest LAKE ?

The world’s largest lake is the Caspian Sea , between Iran and the Russian Commonwealth. Although it is called a sea , it is not connected with the ocean, but is a very large inland lake . Its total area is 371800 square kilometers. It is in a desert so a lot of water evaporates , and the water is very salty.

The largest fresh water lake is Lake Superior, between the USA and Canada. It covers 82,500 square kilometers.The worlds highest lake is an unnamed glacial lake near Mount Everest. It is 5880 metres above sea level. Lake Titicaca is the highest navigable lake.

Which is the longest River ?

The three longest rivers in the world are the Nile in Africa: 6670 kilometres long ; the Amazon in South America : 6448 kilometres long: and the Mississippi – Missouri in North America: 5970 kilometres long.

The river Amazon is larger than the river Nile and contains for more water. Boats can travel much further upstream . The average discharge of the Nile is 3120 cubic metres per second, and the Amazon has an average discharge of 180, 000 cubic metres per second.

Where Does your tap water comes from ?

We break into the water cycle to obtain our water . Then we purify it and pipe it to our homes.

Rain water can be collected from the roof and stored in tanks. In some places water is pumped out of rivers or lakes and piped to homes. Elsewhere, the water we use comes from underground springs or boreholes .It is pumped up from permeable rocks such as chalk. But in most large cities, there is not enough surface water for everyone, and water may be stored nearby, in huge reservoirs.

Where is the deepest part of the ocean ?

The deepest part of the ocean was found in 1951 by the surveys ship Challenger. Echo-
Surroundings showed part of Mariana Trench , south of Japan, to be 10,900 metres deep.

In 1960 the US Navy bathyscaphe Trieste decended to the bottom of the Challenger Deep. The Mariana Trench is one of many deep trenches around the edges of the pacific Ocean. These V- Shaped trenches are parallel to a continent or line of islands.

What is an ATOLL ?

An atoll is coral reef which forms an almost complete circle around a lagoon.
The circular coral reefs of most atolls reach deep down in to water where no coral can grow. As the diagram shows, atolls may once have been reefs in shallow water surrounding a volcano. As the islands sinks, or the sea level changes , the coral continues to grow. The original island disappears far below the lagoon, and the reef forms an atoll.

Where is the Driest Place on Earth ?

Atacama Desert

In the Atacama Desert in Northern Chile, The first rain for 400 years fell in 1971. All Deserts are dry, but the Atacama is the driest.

Cairo, in the eastern Sahara, average 28 millimetres of rain a year, and Bahrain on the edge of Arabian Desert, has 81 millimetres. Not all the dry parts of the Earth are also hot – the Polaar lands are also very dry.

Where are the world’s hottest Places ?

The highest shade temperature on record is 58 C in September 1922 at Al ‘ Aziziyah in the Sahara Desert in Libiya. Nearly as hot was the 56.7 C recorded in Death Valley in USA in July 1913.

The eastern Sahara has more sunshine than anywhere else: sunshine has been recorded for 4300 hours in a year, which is an average of 11 hours 47 minutes per day.

Where are FIORDS found?

Fiords are long, narrow steep – sided inlets of the sea. They were made by glaciers Which depended the Valleys along which they flowed. After the glaciers disappeared,Their U shaped valleys were flooded by the sea to form fiords.

Fiords are found on mountainous coasts which have been eroded by glaciers. The fiords
Of Norway are famous and are among the longest in the world. Sogne Fird is 183 kilometres long , and its average width is 4.75 kilometres. It is 1245 metres deep. Fiords are also found along the coasts of Inceland, Greenland and New Zealand.

Where are the biggest Ice Berg Found ?

The iceberg with the biggest area are the tabular icebergs that break away from Antarctica . Te largest iceberg every seen was over 31,000 square kilometers (bigger than Belgium).

The tallest iceberg break away from Greenland .THE TALLEST one ever seen 167 meters above the water.Eight - ninth of the iceberg was below the sea.

Which are the world Biggest expanses of ICE ?

Just over 10 percnet of land surface of the world is permanently coverred by ice . Most of the worldsice (87 %) is in Antractica.The artic has 12.5 % ( mainly covering Greenland) and the rest is found in the glaciers which exist on every continent.

The longest glacier is the Lambert-Fisher Ice Passage in Antractica, which is 515 kilometers long .PetermannsGlacier in Greenland is the largest glacier in the northen hemisphere, 40, kilometres out to sea.

Where is the Pacific 'Ring of Fire' ?

Pacific 'Ring of Fire'

Seen on a map. the Pacific Ocean appears surrounded by a ring of fiery volcanic activity.
There are many active volcanoes, and some of the world's highest are in the Andes and the mountains of Central America .Others are found in the mountains of western USA and Alaska , in the Kamchatka peninsula and in Siberia, Japan,Papua New Guinea and New Zealand.

Where is the largest Active Volcano ?

The highest , active volcanoes on land are in the Andes , in South America. The highest of these is Ojos del Salada, which is 6885 metres high.But even larger volcanoes rise from the floor of the Pacific Ocean and from the islands of Hawai.

Mauna Loa , on Hawaii, is probably largest active volcano in the world .It rises 4170 metres above sea level, but its base is 5180 metres below sea level.This base is roughly oval in shape :119 kilometres long and 85 kilometres across . The lava from Hawaiian volcanoes is very liquid and flows for long distances.Mauna Lao erupts every 3.5 years. The nearby Kilauea Crater, south - east of the main volcano , is filled with red hot lava.

Where are diamonds and gold found ?

Diamond were formed deep underground in conditions of intense heat and pressure.Artificial diamonds can be made n factories .Pure carbon is baked under gret pressure to over 1400C . NAtural diamonds were probably found under similar conditions.

Diamonds are mined in South Africa ,Tanzania ,Siberia,Africa ,India,Indonesia, Brazil,Australia and the former Soviet republics..Gold is found in mineral veins in rocks , or in gravels which have been washed away from areas where gold -bearing rocks have been reoded.Prospectors may pan the gravel in streams for grains of gold.Half of the world's gold is mined in South Africa.

Where is the San Andreas Fault ?

The San Andreas fault

The San Andreas fault is in western California , near the Pacific coast the USA.
The San Andreas fault and the Fair-weather fault in Alaska from the boundary between the Pacific Plate and the North American Plate. The pacific Plate is slowly rotating anti -clockwise . West of the San Andreas fault ,the land is moving north-westwards. As a result, land along the fault is moving at five centimeters every year. Sometimes, however, the movement is more dramatic , leading to earthquakes.

Where is the great Rift Valley ?

The Great Rift Valley
This is a series of linked rift valleys which stretch for 6500 kilometers from the north of River Jordon, via the Dead Sea and the Red Sea , through Ethiopia and east Africa to the coast near the mouth of Zambezi River.

The Great Rift VAlley is between 30 and 60 kilometers wide and has steep scarps on each side for most of its lenght.Elsewhere there are long, narrow deep lakes such as Turkana, Mobutu, Tanganyaika and Malawi in East Africa the route of the Rift Valley splits into two branches.

What kind of soil is Fertile ?

A fertile soil is humus, bacteria and minerals .It also has enough water and a good texture.
The rock beneath the soil is important. Permeable rocks, such as sandstone , make the soil
light and dry.

Very limey (alkaline ) soils are bad for some plants .Broken- down rock fragments provide the
minerals which plants need. Climate and natural vegetation are also important. Plants need organic matter, called humus. This contains nutrients plants need for growth.

Why do Glaciers appear?

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Why do lakes Sometimes Disappear ?

Many lakes have vanished . Some have been filled up, the water of others has flowed away,
and other lakes in very hot countries have simply dried up.

Lakes can be filled up with material brought down by rivers. Deltas in a lake can eventually fill up the whole lake, which becomes an almost flat plain.Some lakes dry up because of evaporation, and some disappear and return, such as lake Eyre in Australia .It is Huge lake,but it disappears in dry weather.

Why do some rivers have Deltas ?

A Delta is shaped like a triangle , which is also the shape of the Greek letter D, called Delta.
A river delta is caused by deposits at the mouth of the river.This happens when the river
transports more slit to its mouth than can be removed by currents or tides.

The Mediterranean Sea has a very small tidal range , so big rivers like the Nile and the Rhone have very big deltas.deltas are less common rivers that flow to oceans and tidal seas.

What kinds of Clouds can we see ?

Clouds are made of millions of tiny water droplets or ice crystals suspended in the air. They
are named according to their shape and heaight.

Cirrostratus is a hin , almost transparent layer of cloud at a high level. Altostratus is a thicker layer of cloud at a higer level. Nimbostratus forms at a lower level, whicle stratus cluods are layers within 500 metres of the Earth's surface .'Puffy' clouds, known as cumulus clouds, are called altocumulus at a high level.When they join together they form stratocumulus.
Cumulonimbus are towering thunder clouds. A third type of cloud is cirrus, wisps of clouds
high in the sky.

What is the Atmosphere Made Of ?

The Atmosphere is the air which surrounds the planet Earth. The gases in the air allow plants,
animals and humans to live. The dampness ad movement of the air near the Earth causes our
weather.The atmosphere also sheilds us from the Sun's harmful rays and from falling meteroites.

Air is made up of many gases . The most common are nitrogen(78%) and oxygen (21%).
There are small amounts of other gases, including argon, water vapour and carbon dioxide.

Why do clouds Form ?

A cloud is made up of tiny droplets of water or ice. When cloud forms, the invisible vapour in the air condences in to visible droplets of water.

All air contains water vapour . Warm air can hold more waer vapour than cold air. if the air cools down, it cannot hold so much water vepour, and it turns into tiny droplets of water. Air coold down when it rises, because the higher in the atmostphere it goes, the cooler itgets, When it rains , tiny droplets in a cloud from bigger drops which fall to earth.

Why Do the Tides Rise And Fall ?

The water in the oceans is held close to the earth by gravity. But the Moon and Sun also have some 'pull' on the earth. The Moon's gravity affects water in the oceans.The sea is 'pulled' slightly towards the Moon, causing a bulge, or high tide. On the opposite side, the sea is pushed away, causing a second bulge.

High tided occur twice in about 25 hours.This is because at the same time as the earth is rotating on its axis , the Moon is travelling round the Earth(every 27 days).

Why do earthquakes occur only in some parts of the world?

The map shows where earthquakes have happened . These occur near the edges of the Rearth's Crustal plates.

The plates are slowly moving together or apart. For instance , one zone encircles the Pacific. Here , the floor of the Pasific is being pushed down under the continents, and this gradual movement of Pacific plates agaist the continental plates causes earthquakes. Other zones are in the Mediterranean and the Atlantic.

Where do Gysers occur ?

All geysers occur in areas of volcanic activity, but not all volcanic areas have geysers. They only occur where water can soak through cracks in the rocks and collect underground

Here the water is heated under pressure, and as it starts to bubble out there is a sudden gush of steam and hot water high in to the air.

Why do volcanoes erupt?

The lava of volcanoes is molten rock , called magma.Some magma rises straight from the Eart's
mantle to the surface .Some is stored in a magma chamber in the crust, where the gases collect
and help to drive the magma out.

The upper part of the mantle, under the Earth's crust, is nealry molten. Magma contains
several gases, and bubbles of this expand near the surface and drive the magma out as an eruption . Volcanice eruptions vary from place to place, mainly according to how fluid or gasous the lava is .

Why do the continents move about ?

The crust of the Earth is a relatively thin layer. Scientist beleive it is divided into huge sections called "plates". These are moved very slowly by convection currents inside the Earth.

The scientist Alfred Wegener suggested in 1915 that the continents might have moved. They had noticed that their shapes fit together like a jigsaw. His Theory was called"Continental Drift".

Why are Fossils important to geologists?

Fossils
Fossils help geogolists to put different kinds of rocks in the same age group. Fossils also give information about the conditions that existed when they were alive. and similar fossils in different places help in the study of continental drift.

The most useful fossils are of plant and animals which lived in a wide variety of places , but only for a short period of time .thsese are called index fossils.

Why did dianasaurs die out so suddenly?

Dinasaurs became extinct about 65 million years ago, at the end of Cretaceous times. They had existed for 130 million years. No one knows why they died out.

Many other types of animals died out at the same time as the dianasaurs, including flying and sea reptiles. but few reptiles did survive , including turtles, lizardsand snakes . there are many theories to explain why the dinasours died out ,including changes of climate and vegetation, cold winters, new parsites and diseases.

When did Sea Charts Come Into Use?

Sea Chart

The earliest record of a sea chart dates from 1270 when Louis IX of france studied a chart on
board a Genoese ship during the Eighth Crusade. The earliset navigators kept close to land or drifted with ocean currents.
Once the compass was used , ships could sail more directly from one port to another.The Chinese and Arabs may have used sea charts befor Europeans, but none survive From about 1200, compassed and rudders were used on european ships . Navigators used portolani, books which listed ports,landmarks, distances and navigational advice.

When did the old and new worlds seperate?

The continents of the old world (Europe, Asia and Africa ) and the New world The Americas have been slowly drifting on the surface of the Earth since our planet became solid . In the last 150 million years, the Atlantic has gradually opened up, seperating the Americas from Africa and Europe.
Alaska and Siberia were once joined , but at present Alaska and Siberiaare seperated by the Bering Strait.