المساعد الشخصي الرقمي

مشاهدة النسخة كاملة : طلب المساعدة في انجاز بحث


chaimaa32
2009-04-12, 19:14
الرجاء من طلاب السنة ثانوي العلوم التجريبية مساعدتي في انجاز بحث الانجليزية الصفحة 132

acil.acil4
2009-04-15, 08:01
مرحبا
الرجاء قولي ما هو موضوع البحث لأنه ليس لدي كتاب و ان شاء الله افيدك

chaimaa32
2009-04-16, 22:14
موضوع البحث عن الكوارث الطبيعية وشكرا

youyou17
2009-04-17, 12:06
A natural disaster is the effect of a natural hazard (http://en.wikipedia.org/wiki/Natural_hazard) (e.g. flood (http://en.wikipedia.org/wiki/Flood), volcanic eruption (http://en.wikipedia.org/wiki/Volcanic_eruption), earthquake (http://en.wikipedia.org/wiki/Earthquake), or landslide (http://en.wikipedia.org/wiki/Landslide)) that affects human activities. Human vulnerability, exacerbated by the lack of planning or appropriate emergency management (http://en.wikipedia.org/wiki/Emergency_management), leads to financial, environmental or human losses. The resulting loss depends on the capacity of the population to support or resist the disaster, and their resilience.[/URL] This understanding :) is concentrated in the formulation: "disasters occur when hazards meet vulnerability (http://en.wikipedia.org/wiki/Natural_disaster#cite_note-0)." A natural hazard will hence never result in a natural disaster in areas without vulnerability, e.g. strong earthquakes in uninhabited areas. The term natural has consequently been disputed because the events simply are not hazards or disasters without human involvement.
(http://en.wikipedia.org/wiki/Natural_disaster#cite_note-2)Earthquakes

An Earthquake is a sudden shaking or vibration of the Earth's crust.The vibrations may vary in magnitude. The earthquake has point of origin underground called the "focus". The point directly above the focus on the surface is called the"epicentre". Earthquakes by themselves rarely kill people or wildlife. It is usually the secondary events that they trigger, such as building collapse, fires, tsunamis and volcanoes, that are actually the human disaster. As many of these could be avoided by better construction, safety systems, early warning and evacuation planning, the term unnatural disaster is not unwarranted.
Earthquakes are caused by the discharge of stress accumulated along geologic faults.
Main article: List of earthquakes (http://en.wikipedia.org/wiki/List_of_earthquakes)
Some of the most significant earthquakes (http://en.wikipedia.org/wiki/Earthquake) in recent times include:


The 2004 Indian Ocean earthquake (http://en.wikipedia.org/wiki/2004_Indian_Ocean_earthquake), the second largest earthquake in recorded history, registering a moment magnitude (http://en.wikipedia.org/wiki/Moment_magnitude_scale) of 9.3. The huge tsunamis (http://en.wikipedia.org/wiki/Tsunami) triggered by this earthquake cost the lives of at least 229,000 people.
The 7.6-7.7 2005 Kashmir earthquake (http://en.wikipedia.org/wiki/2005_Kashmir_earthquake), which cost 79,000 lives in Pakistan (http://en.wikipedia.org/wiki/Pakistan).
The 7.7 magnitude July 2006 Java earthquake (http://en.wikipedia.org/wiki/July_2006_Java_earthquake), which also triggered tsunamis (http://en.wikipedia.org/wiki/Tsunami).

. Volcanic eruptions


(http://en.wikipedia.org/wiki/File:Puu_Oo_cropped.jpg)
(http://en.wikipedia.org/wiki/File:Puu_Oo_cropped.jpg)

(http://en.wikipedia.org/wiki/Pu%27u_%27%C5%8C%27%C5%8D)




An Eruption may in itself be a disaster due to the explosion of the volcano or the fall of rock but there are several effects that may happen after an eruption that are also hazardous to human life.
Lava (http://en.wikipedia.org/wiki/Lava) may be produced during the eruption of a volcano a material consisting of superheated rock. There are several different forms which may be either crumbly or gluey. Leaving the volcano this destroys any buildings and plants it encounters.
Volcanic ash (http://en.wikipedia.org/wiki/Volcanic_ash) - generally meaning the cooled ash - may form a cloud, and settle thickly in nearby ********s. When mixed with water this forms a concrete like material. In sufficient quantity ash may cause roofs to collapse under its weight but even small quantities will cause ill health if inhaled. Since the ash has the consistency of ground glass it causes abrasion damage to moving parts such as engines.
Supervolcanos (http://en.wikipedia.org/wiki/Supervolcano) : According to the Toba catastrophe theory (http://en.wikipedia.org/wiki/Toba_catastrophe_theory) 70 to 75 thousand years ago a super volcanic event at Lake Toba reduced the human population to 10,000 or even 1,000 breeding pairs creating a bottleneck in human evolution. The main danger from a supervolcano is the immense cloud of ash which has a disastrous global effect on climate and temperature for many years.
Pyroclastic flows (http://en.wikipedia.org/wiki/Pyroclastic_flows) consist of a cloud of hot volcanic ash which builds up in the air above a volcano until it collapses under its own weight and streams very rapidly from the mountain burning anything in its path. It is believed that Pompeii was destroyed by a pyroclastic flow.


[

:


The Huang He (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=9) (Yellow River) in China (http://en.wikipedia.org/wiki/China) floods particularly often. The Great Flood of 1931 (http://en.wikipedia.org/wiki/1931_Huang_He_flood) caused between 800,000 and 4,000,000 deaths.
The Great Flood of 1993 (http://en.wikipedia.org/wiki/Great_Flood_of_1993) was one of the most costly floods in United States (http://en.wikipedia.org/wiki/United_States) history.
The 1998 Yangtze River Floods (http://en.wikipedia.org/wiki/1998_Yangtze_River_Floods), also in China (http://en.wikipedia.org/wiki/China), left 14 million people homeless.
The 2000 Mozambique flood (http://en.wikipedia.org/wiki/2000_Mozambique_flood) covered much of the country for three weeks, resulting in thousands of deaths, and leaving the country devastated for years afterward.

Tropical cyclones (http://en.wikipedia.org/wiki/Tropical_cyclone) can result in extensive flooding and storm surge (http://en.wikipedia.org/wiki/Storm_surge), as happened with:


Bhola Cyclone (http://en.wikipedia.org/wiki/Bhola_Cyclone), striking East Pakistan (http://en.wikipedia.org/wiki/East_Pakistan) (now Bangladesh (http://en.wikipedia.org/wiki/Bangladesh)) in 1970,
Typhoon Nina (http://en.wikipedia.org/wiki/Typhoon_Nina_%281975%29), striking China (http://en.wikipedia.org/wiki/China) in 1975,
Tropical Storm Allison (http://en.wikipedia.org/wiki/Tropical_Storm_Allison), which struck Houston, Texas (http://en.wikipedia.org/wiki/Houston,_Texas) in 2001 and
Hurricane Katrina (http://en.wikipedia.org/wiki/Hurricane_Katrina), which left most of New Orleans (http://en.wikipedia.org/wiki/New_Orleans) under water in 2005. Much of the flooding was due to the failure of the city's levee system.

Limnic eruptions


(http://en.wikipedia.org/wiki/File:Cow_killed_by_Lake_Nyos_gasses.jpg)
(http://en.wikipedia.org/wiki/File:Cow_killed_by_Lake_Nyos_gasses.jpg)

(http://en.wikipedia.org/wiki/Limnic_eruption)


A limnic eruption (http://en.wikipedia.org/wiki/Limnic_eruption) occurs when CO2 (http://en.wikipedia.org/wiki/Carbon_dioxide) suddenly erupts from deep lake water, posing the threat of suffocating wildlife, livestock and humans. Such an eruption may also cause tsunamis (http://en.wikipedia.org/wiki/Tsunami) in the lake as the rising CO2landslides (http://en.wikipedia.org/wiki/Landslides), volcanic (http://en.wikipedia.org/wiki/Volcanic) activity, or explosions can trigger such an eruption.To date, only two limnic eruptions have been observed and recorded: displaces water. Scientists believe


In 1984, in Cameroon (http://en.wikipedia.org/wiki/Cameroon), a limnic eruption in Lake Monoun (http://en.wikipedia.org/wiki/Lake_Monoun) caused the deaths of 37 nearby residents
At nearby Lake Nyos (http://en.wikipedia.org/wiki/Lake_Nyos) in 1986 a much larger eruption killed between 1,700 and 1,800 people by asphyxiation (http://en.wikipedia.org/wiki/Asphyxiation).


[edit (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=12)] Tsunamis


(http://en.wikipedia.org/wiki/File:2004-tsunami.jpg)



Tsunami can be caused by undersea earthquakes as the one caused in Ao Nang (http://en.wikipedia.org/wiki/Ao_Nang), Thailand by the 2004 Indian Ocean Earthquake (http://en.wikipedia.org/wiki/2004_Indian_Ocean_Earthquake), or by landslides such as the one which occurred at Lituya Bay (http://en.wikipedia.org/wiki/Lituya_Bay), Alaska (http://en.wikipedia.org/wiki/Alaska) in.


Ao Nang (http://en.wikipedia.org/wiki/Ao_Nang), Thailand (2004). The 2004 Indian Ocean Earthquake (http://en.wikipedia.org/wiki/2004_Indian_Ocean_Earthquake) created the Boxing Day Tsunami (http://en.wikipedia.org/wiki/Boxing_Day_Tsunami) and disaster at this site.
Lituya Bay (http://en.wikipedia.org/wiki/Lituya_Bay), Alaska (1953). See paragraph three (3) of the entry. A mega-tsunami (http://en.wikipedia.org/wiki/Mega-tsunami) occurred here, the largest ever recorded.
This would also fit within Land movement category because it starts with an earthquake.



(http://en.wikipedia.org/wiki/Weather_disasters)





[Cyclonic storms

Main articles: tropical cyclone (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=15) and cyclone (http://en.wikipedia.org/wiki/Cyclone)
Cyclone, tropical cyclone, hurricane, and typhoon are different names for the same phenomenon a cyclonic storm system that forms over the oceans. The deadliest hurricane ever was the 1970 Bhola cyclone the deadliest Atlantic hurricane was the Great Hurricane of 1780 which devastated Martinique St. Eustatius and Barbados. Another notable hurricane is Hurricane Katrina which devastated the Gulf Coast of the United States in 2005.

[ Droughts

Well-known historical droughts (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=16) include:


1900 India killing between 250,000 and 3.25 million.
1921-22 Soviet Union in which over 5 million perished from starvation due to drought
1928-30 northwest China resulting in over 3 million deaths by famine.
1936 and 1941 Sichuan Province China resulting in 5 million and 2.5 million deaths respectively.
As of 2006 Western Australia New South Wales Victoria Australia Victoria and Queensland states of Australia have been under drought conditions for five to ten years. The drought is beginning to affect urban area populations for the first time.
In 2006 Sichuan Province China experienced its worst drought in modern times with nearly 8 million people and over 7 million cattle facing water shortages.




[ Fire

Main article: List of forest fires (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=20)
Wildfires (http://en.wikipedia.org/wiki/Wildfire) are an uncontrolled fire burning in wildland (http://en.wikipedia.org/wiki/Wildland) areas. Common causes include lightning (http://en.wikipedia.org/wiki/Lightning) and drought (http://en.wikipedia.org/wiki/Drought)arson (http://en.wikipedia.org/wiki/Arson). They can be a threat to those in rural areas and also wildlife (http://en.wikipedia.org/wiki/Wildlife). but wildfires may also be started by human negligence or


(http://en.wikipedia.org/wiki/List_of_epidemics)

(http://en.wikipedia.org/wiki/File:Colorized_transmission_electron_micrograph_of _Avian_influenza_A_H5N1_viruses.jpg)
(http://en.wikipedia.org/wiki/File:Colorized_transmission_electron_micrograph_of _Avian_influenza_A_H5N1_viruses.jpg)
Avian influenza (http://en.wikipedia.org/wiki/Avian_influenza)


An epidemic (http://en.wikipedia.org/wiki/Epidemic) is an outbreak of a contractible disease (http://en.wikipedia.org/wiki/Disease) that spreads at a rapid rate through a human population. A pandemic (http://en.wikipedia.org/wiki/Pandemic) is an epidemic whose spread is global. There have been many epidemics throughout history, such as Black Death (http://en.wikipedia.org/wiki/Black_Death). In the last hundred years, significant pandemics include:


The 1918 Spanish flu (http://en.wikipedia.org/wiki/Spanish_flu) pandemic, killing an estimated 50 million people worldwide
The 1957-58 Asian flu (http://en.wikipedia.org/wiki/Asian_flu) pandemic, which killed an estimated 1 million people
The 1968-69 Hong Kong flu (http://en.wikipedia.org/wiki/Hong_Kong_flu) pandemic
The 2002-3 SARS (http://en.wikipedia.org/wiki/SARS) pandemic
The AIDS (http://en.wikipedia.org/wiki/AIDS) epidemic, beginning in 1959

Other diseases that spread more slowly, but are still considered to be global health emergencies by the WHO (http://en.wikipedia.org/wiki/WHO) include:


XDR TB (http://en.wikipedia.org/wiki/XDR_TB), a strain of tuberculosis (http://en.wikipedia.org/wiki/Tuberculosis) that is extensively resistant to drug treatments
Malaria (http://en.wikipedia.org/wiki/Malaria), which kills an estimated 1.5 million people each year
Ebola hemorrhagic fever (http://en.wikipedia.org/wiki/Ebola_hemorrhagic_fever), which has claimed hundreds of victims in Africa (http://en.wikipedia.org/wiki/Africa) in several outbreaks (http://en.wikipedia.org/wiki/Outbreak)


[Famine

Main article: List of famines (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=23)
In modern times, famine has hit Sub-Saharan Africa (http://en.wikipedia.org/wiki/Sub-Saharan_Africa) the hardest, although the number of victims of modern famines is much smaller than the number of people killed by the Asian famines of the 20th century.

[


Main article: solar flare (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=24)
A solar flare (http://en.wikipedia.org/wiki/Solar_flare) is a phenomenon where the sun (http://en.wikipedia.org/wiki/Sun) suddenly releases a great amount of solar radiation (http://en.wikipedia.org/wiki/Solar_radiation), much more than normal. Some known solar flares include:


An X20 event on August 16 (http://en.wikipedia.org/wiki/August_16), 1989 (http://en.wikipedia.org/wiki/1989)
A similar flare on April 2 (http://en.wikipedia.org/wiki/April_2), 2001 (http://en.wikipedia.org/wiki/2001)
The most powerful flare ever recorded, on November 4 (http://en.wikipedia.org/wiki/November_4), 2003 (http://en.wikipedia.org/wiki/2003), estimated at between X40 and X45
The most powerful flare in the past 500 years is believed to have occurred in September 1859






(http://en.wikipedia.org/wiki/Hypernova)

[ Insurance

Natural disasters play a major role in the [URL="http://en.wikipedia.org/wiki/Insurance"]insurance (http://en.wikipedia.org/w/index.php?title=Natural_disaster&action=edit&section=29) industry, which pays for certain damages arising from hurricanes, wildfires, and other catastrophes. Large reinsurance (http://en.wikipedia.org/wiki/Reinsurance) companies are particularly involved.[ (http://en.wikipedia.org/wiki/Natural_disaster#cite_note-3)

acil.acil4
2009-04-17, 18:13
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Volcanoes considered the unique natural phenomena which has attracted the attention of the human foot, which plays a great role in the geological processes that affect the evolution of the history of the earth's crust and shape. This is because the most affected parts of the earth's crust and the processes Alandfaip subject to the contribution of the formation processes Alandfaip. According to a study to identify the volcanic centers of study of earthquakes and volcanoes branch of geology, which has become known as a stand-alone volcanology Volcanology. Volcanoes and associated minerals and raw materials are very important in economic terms.
The definition of the volcano:
The volcano is the place out or emitting materials, Alzirip hot with steam and gases associated with the depth of the earth's crust occurs during the vent or cracks. Accumulated magmatic flow, or by type of land forms are different conical hills or high volcanic mountains

Parts of volcanoes:
If you look at the form you will find that it consists of:

1 - Mount conic:
Itrkp of rocky debris, or LAVA rigid. It Iqzvha material from the volcano crater and all or some of them in the molten state.
2 - THE BRINK: It is a cavity almost round shape at the top of cone, the wider the range from a few thousand meters. And emerge from the crater at gas and the masses of rock and mortar and molten lava and materials (LAVA) may be of the volcano's crater more than a secondary part of the main crater at its summit as seen in the figure:
3 - chimney or township: the channel extends from the bottom of the crater to the bottom of a bakery, as they relate Alzir underground. And volcanic material, which is pushing to the crater. And sometimes the throat with the volcano.
In addition to the main chimney, it may be several chimneys of the volcano-related secondary Balfohat
file:///C:/DOCUME%7E1/HAMCHE%7E1/LOCALS%7E1/Temp/msohtmlclip1/01/clip_image002.jpg

Volcanic material:

Out of volcanic rock debris while Thoradtha solid and liquid materials.
1 - rock debris:

Derives the result of volcanic explosions rock the heart of the debris of various types and sizes are usually in the first period of volcanic eruptions. And rock debris derived from the rigid crust, which are extracted from the walls of the neck owing to the payment and materials Allava gas emanating from Alzir strongly Itrkp, violence and rock debris of the different sizes, including blocks in the rock, ****ls and pebbles, sand and volcanic dust.
2 - gases:
Graduated from the volcanic activity during the gas water vapor, which derives a great amount for the withdrawal of a huge mixed with dust and other gases. This is building steam, causing the heavy rain falling in the vicinity of the volcano. Accompanied by explosions and rainfall of an electric lighting friction arising from the ashes of volcanic grains together and as a result of air turbulence, the promise of high-temperature water vapor, breathing volcano, the most important multi-hydrogen gas, chlorine, sulfur, nitrogen, carbon and oxygen.
3 - Allava:
Are the masses of liquid Tlfezha volcanoes, with a temperature between 1000 and 1200. Allava stems from the crater, as the overflow through the cracks and fractures in the volcanic cone, those fractures created by the explosions, the pressure blocks Alzir, Allava The nature and appearance of the chemical composition of the blocks Alzir which emits two types namely:
A - the beginning of the Lava Light Color:
This is how much of the viscosity, and therefore a slow flow, as Allava which emanated from the volcano Bailey (Almrtnik Islands in the Caribbean) in 1902 was a sticky-intensive to the extent that it was not time to move, accumulate, and took up a tower to rise above the crater was about 300 m , and soon after the break and crash a result of explosions caused by the exit gases.
B - LAVA heavy dark color:
Ava is basaltic, and characterized as a liquid and moving to a large extent, the flow in the form of streams on the slopes of the volcano, and when these emerge through fractures Allava great extension, it spread over vast areas to a spacious plateaus, like Plateau Plateau Habasha Aldkin India and Columbia Heights in North America.
Forms of volcanoes:
1 - volcanic rock debris:
Different form of the volcanic cone, depending on the material Itrkp them. If the cone Itrkp School of rock debris, we found a very high slope for the area occupied by the base. Here we find the gradient of 30 degrees was up to 40 degrees Celsius, these forms arise and usually the result of volcanic eruptions. The Islands of Indonesia.
2 - Alhillip volcanoes:
And arise as a result of accumulation and exit Allava on the brink of a major and a few that seem to rise to the large area occupied by the rules. The peaks seem like a convex, translucent horny plates Bhiab Thdba easy, hence the name Alhillip volcanoes have arisen from the influx of these Cones Mshorat Allava high temperature and great liquidity, which has spread over large areas and this is the best representation of Alhillip volcanoes volcanoes in the Hawaiian Islands Kbarakan Monallowa-high in 4100, which seems like a spacious dome descending Hina easy.
3 - stratified volcanoes:
Stratified volcanic common type exist, they form the center of the former types of materials adapted Mkrotadtha rock debris flows Allava is dropping while the restless volcano eruptions.
Alloafez are emerging from the volcano during the successive layers of the explosions on each other, and some of them consisting of the rough and another section of the minutes, and between this and that Allava overlap in the tapes of a few fish. It is this type of stratified arise in the installation of a cone, and this form of Mayon volcano more active volcanoes of the Philippines at the present time.

The geographical distribution of volcanoes:
Volcanoes spread over long ranges shown on the surface of the Earth:
1 - The scale along the Pacific Ocean and is sometimes known as Ring of Fire, it extends on the east coast of the Pacific over the Andes to Central America and Mexico, and over the hills to the west of North America and the Aleutian Islands to the east coast of the continent of Asia to the islands of Japan, the Philippines and then to Islands of Indonesia and New Zealand.
2 - there are many volcanoes in the Pacific Ocean and some of the same resulted in a huge great room and appeared to stand above the water. Volcanoes, including the Hawaiian Islands, which were based bases in the Pacific at a depth of about 5000, and rise above the surface of water more than in 4000, bringing the total height from the bottom of the Atlantic Ocean to the peaks of about 9000
3 - South Europe, overlooking the Mediterranean Sea and its adjacent islands. The most famous active volcanoes here Vezov near Naples, Italy, and Sicily and Etna Islands Astro Mbuli (a beacon of the Mediterranean Sea) in the Islands unparalleled.
4 - Asia and the Western Highlands months and Ararat volcanoes Aliuzenz.
5 - ranging from eastern Africa and the Kilimanjaro Brkinh months.





The effects of volcanoes:
1 - in the formation of the Earth's surface:
We can see above that the effects of volcanoes in shaping the Earth's surface, it created the majestic mountains, vast plateaus. When extinguished, arising in the cavities of their pores lakes in those rainforests.
2 - in human activity:
Strange that no human habitation near the volcanoes plays in order to be safe from the dangers, as we find them living in the vicinity, but also on the slopes. Fberkan Vezov surrounded by villages and towns and covered with gardens and fruit orchards and vineyards spread over all of its aspects, even near the top. The agriculture is also on the slopes of a volcano (twelve) on the island of Sicily in 1200, even higher in the fertile soil is composed of black basalt, which flows over the region during historical times.
These volcanoes are ruthless when it arises from another and destroying the village or the other could rest along the main road on the lower slopes of the volcano and at the end of twelve flows Allava flowing eternal evidence indicates a danger that the threat to the region.
The famous island of Java Berakinh rebel and active volcanoes, in fact, more than all the volcanoes in the world and the amount of Alloafez rashes that have emerged since 1500, however, we find the island full of the population, are the most intensive agricultural regions of the world population for the area and is inhabited by about 75 million people due to the above, as fertility volcanic soil, which was established by the interest of the volcanoes and function prediction of volcanic eruptions and warn the population before the volcanic eruptions, which reduces the risk of their occurrence.

acil.acil4
2009-04-17, 18:16
Volcanoes considered the unique natural phenomena which has attracted the attention of the human foot, which plays a great role in the geological processes that affect the evolution of the history of the earth's crust and shape. This is because the most affected parts of the earth's crust and the processes Alandfaip subject to the contribution of the formation processes Alandfaip. According to a study to identify the volcanic centers of study of earthquakes and volcanoes branch of geology, which has become known as a stand-alone volcanology Volcanology. Volcanoes and associated minerals and raw materials are very important in economic terms.
The definition of the volcano:
The volcano is the place out or emitting materials, Alzirip hot with steam and gases associated with the depth of the earth's crust occurs during the vent or cracks. Accumulated magmatic flow, or by type of land forms are different conical hills or high volcanic mountains

Parts of volcanoes:
If you look at the form you will find that it consists of:

1 - Mount conic:
Itrkp of rocky debris, or LAVA rigid. It Iqzvha material from the volcano crater and all or some of them in the molten state.
2 - THE BRINK: It is a cavity almost round shape at the top of cone, the wider the range from a few thousand meters. And emerge from the crater at gas and the masses of rock and mortar and molten lava and materials (LAVA) may be of the volcano's crater more than a secondary part of the main crater at its summit as seen in the figure:
3 - chimney or township: the channel extends from the bottom of the crater to the bottom of a bakery, as they relate Alzir underground. And volcanic material, which is pushing to the crater. And sometimes the throat with the volcano.
In addition to the main chimney, it may be several chimneys of the volcano-related secondary Balfohat
file:///C:/DOCUME%7E1/HAMCHE%7E1/LOCALS%7E1/Temp/msohtmlclip1/01/clip_image002.jpg

Volcanic material:

Out of volcanic rock debris while Thoradtha solid and liquid materials.
1 - rock debris:

Derives the result of volcanic explosions rock the heart of the debris of various types and sizes are usually in the first period of volcanic eruptions. And rock debris derived from the rigid crust, which are extracted from the walls of the neck owing to the payment and materials Allava gas emanating from Alzir strongly Itrkp, violence and rock debris of the different sizes, including blocks in the rock, ****ls and pebbles, sand and volcanic dust.
2 - gases:
Graduated from the volcanic activity during the gas water vapor, which derives a great amount for the withdrawal of a huge mixed with dust and other gases. This is building steam, causing the heavy rain falling in the vicinity of the volcano. Accompanied by explosions and rainfall of an electric lighting friction arising from the ashes of volcanic grains together and as a result of air turbulence, the promise of high-temperature water vapor, breathing volcano, the most important multi-hydrogen gas, chlorine, sulfur, nitrogen, carbon and oxygen.
3 - Allava:
Are the masses of liquid Tlfezha volcanoes, with a temperature between 1000 and 1200. Allava stems from the crater, as the overflow through the cracks and fractures in the volcanic cone, those fractures created by the explosions, the pressure blocks Alzir, Allava The nature and appearance of the chemical composition of the blocks Alzir which emits two types namely:
A - the beginning of the Lava Light Color:
This is how much of the viscosity, and therefore a slow flow, as Allava which emanated from the volcano Bailey (Almrtnik Islands in the Caribbean) in 1902 was a sticky-intensive to the extent that it was not time to move, accumulate, and took up a tower to rise above the crater was about 300 m , and soon after the break and crash a result of explosions caused by the exit gases.
B - LAVA heavy dark color:
Ava is basaltic, and characterized as a liquid and moving to a large extent, the flow in the form of streams on the slopes of the volcano, and when these emerge through fractures Allava great extension, it spread over vast areas to a spacious plateaus, like Plateau Plateau Habasha Aldkin India and Columbia Heights in North America.
Forms of volcanoes:
1 - volcanic rock debris:
Different form of the volcanic cone, depending on the material Itrkp them. If the cone Itrkp School of rock debris, we found a very high slope for the area occupied by the base. Here we find the gradient of 30 degrees was up to 40 degrees Celsius, these forms arise and usually the result of volcanic eruptions. The Islands of Indonesia.
2 - Alhillip volcanoes:
And arise as a result of accumulation and exit Allava on the brink of a major and a few that seem to rise to the large area occupied by the rules. The peaks seem like a convex, translucent horny plates Bhiab Thdba easy, hence the name Alhillip volcanoes have arisen from the influx of these Cones Mshorat Allava high temperature and great liquidity, which has spread over large areas and this is the best representation of Alhillip volcanoes volcanoes in the Hawaiian Islands Kbarakan Monallowa-high in 4100, which seems like a spacious dome descending Hina easy.
3 - stratified volcanoes:
Stratified volcanic common type exist, they form the center of the former types of materials adapted Mkrotadtha rock debris flows Allava is dropping while the restless volcano eruptions.
Alloafez are emerging from the volcano during the successive layers of the explosions on each other, and some of them consisting of the rough and another section of the minutes, and between this and that Allava overlap in the tapes of a few fish. It is this type of stratified arise in the installation of a cone, and this form of Mayon volcano more active volcanoes of the Philippines at the present time.

The geographical distribution of volcanoes:
Volcanoes spread over long ranges shown on the surface of the Earth:
1 - The scale along the Pacific Ocean and is sometimes known as Ring of Fire, it extends on the east coast of the Pacific over the Andes to Central America and Mexico, and over the hills to the west of North America and the Aleutian Islands to the east coast of the continent of Asia to the islands of Japan, the Philippines and then to Islands of Indonesia and New Zealand.
2 - there are many volcanoes in the Pacific Ocean and some of the same resulted in a huge great room and appeared to stand above the water. Volcanoes, including the Hawaiian Islands, which were based bases in the Pacific at a depth of about 5000, and rise above the surface of water more than in 4000, bringing the total height from the bottom of the Atlantic Ocean to the peaks of about 9000
3 - South Europe, overlooking the Mediterranean Sea and its adjacent islands. The most famous active volcanoes here Vezov near Naples, Italy, and Sicily and Etna Islands Astro Mbuli (a beacon of the Mediterranean Sea) in the Islands unparalleled.
4 - Asia and the Western Highlands months and Ararat volcanoes Aliuzenz.
5 - ranging from eastern Africa and the Kilimanjaro Brkinh months.





The effects of volcanoes:
1 - in the formation of the Earth's surface:
We can see above that the effects of volcanoes in shaping the Earth's surface, it created the majestic mountains, vast plateaus. When extinguished, arising in the cavities of their pores lakes in those rainforests.
2 - in human activity:
Strange that no human habitation near the volcanoes plays in order to be safe from the dangers, as we find them living in the vicinity, but also on the slopes. Fberkan Vezov surrounded by villages and towns and covered with gardens and fruit orchards and vineyards spread over all of its aspects, even near the top. The agriculture is also on the slopes of a volcano (twelve) on the island of Sicily in 1200, even higher in the fertile soil is composed of black basalt, which flows over the region during historical times.
These volcanoes are ruthless when it arises from another and destroying the village or the other could rest along the main road on the lower slopes of the volcano and at the end of twelve flows Allava flowing eternal evidence indicates a danger that the threat to the region.
The famous island of Java Berakinh rebel and active volcanoes, in fact, more than all the volcanoes in the world and the amount of Alloafez rashes that have emerged since 1500, however, we find the island full of the population, are the most intensive agricultural regions of the world population for the area and is inhabited by about 75 million people due to the above, as fertility volcanic soil, which was established by the interest of the volcanoes and function prediction of volcanic eruptions and warn the population before the volcanic eruptions, which reduces the risk of their occurrence.

zidane_b
2009-04-17, 19:20
ارجوا انه تم افادتك من الاعضاء السابقين

chaimaa32
2009-04-23, 17:47
شكرا لكم جميعا وجزاكم الله كل خيرا

hiba27
2009-04-24, 14:44
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سر السعادة
2009-04-25, 10:59
يا رب اجد ضالتي هنا انا بالثانية ثانوي وحبيت من يساعدني في البحث عن تجربة علمية

islaminkov
2009-04-28, 13:37
merci a3lokom vous etes de champion alah inajahkom ou inejahna ga3e.
goulou amine

Boby Brars
2009-04-29, 18:16
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sonia22
2009-04-29, 19:06
merci infiniment
moi aussi j'ai besoin de ce projet

Rababe_Gh
2009-05-04, 15:27
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