Earth Science

A:

The Snowy Mountains in the Australian Alps started forming about 860 million years ago by different marine sediments when southeast Australia was covered by the sea, according to Swirk. Natural forces up folded and lifted these rocks, then were later flattened by erosion leaving the sharp edge plateaux seen today. The valleys were formed by river water erosion.

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  • What is the coldest layer of the Earth's Atmosphere?

    Q: What is the coldest layer of the Earth's Atmosphere?

    A: Temperatures can reach lows of -90 degrees Celsius in the mesosphere, making it the coldest layer of the earth's atmosphere. The mesosphere extends above the stratosphere and ranges from 50 km to 87 km above the surface.
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  • Why is the Mississippi River important?

    Q: Why is the Mississippi River important?

    A: The Mississippi River is important due to its necessity in American commerce. Cities such as New Orleans, St. Louis and Minneapolis all get water from the river.
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  • How do glaciers cause erosion?

    Q: How do glaciers cause erosion?

    A: Glaciers erode the land in three primary ways: plucking, abrasion and freeze-thaw. All three manners of erosion combine to make glaciers one of the world’s most powerful agents of erosion.
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  • How do glaciers change the landscape?

    Q: How do glaciers change the landscape?

    A: Glaciers alter the landscape through erosion of the soil and rocks over which they pass. This erosion process leaves a vertical-walled valley similar to an amphitheater at the glacier's sources, according to Reference.com. As they travel through V-shaped valleys, glaciers transform the valley into a U-shape, grinding away cliffs and the bases of slopes. If the ocean fills these valleys, they become fjords.
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  • What is the average temperature of a swamp?

    Q: What is the average temperature of a swamp?

    A: The average temperature range of the world's swamps is between 15 C and 35 C. Swamps fall into two categories: swamp forests and shrub swamps. Bogs are not true swamps because they are not forested, but they are often mislabeled as such.
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  • How do humans affect the ecosystem?

    Q: How do humans affect the ecosystem?

    A: Human activity affects ecosystems in a wide variety of ways, but it primarily does so through agriculture, habitat destruction, water use and fishing. Whenever humans enter a habitat, they tend to reshape it to fit their own needs, destroying the resources that other animals use, which drives them out. The overuse of water drains natural aquifers and alters the local water table, and pollution can negatively affect wildlife populations.
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  • How are striations formed?

    Q: How are striations formed?

    A: Striations are a common feature of rocks that have once been overlain by a moving glacier. The scratches on the rock face are generally straight and all are oriented in the same direction, matching the downhill flow of the ice.
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  • What is collection in the water cycle?

    Q: What is collection in the water cycle?

    A: Collection refers to the process by which water gathers back into bodies of water such as rivers, lakes and oceans. This begins with precipitation, when water falls from the clouds in the form of rain, snow, sleet or hail. A lot of the time, precipitation falls directly into a body of water, but at other times, it soaks into the ground, where plants, people and animals end up drinking it as ground water. Most of the water will end up leaching back into bodies of water through the soil.
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  • Why do natural disasters happen?

    Q: Why do natural disasters happen?

    A: There are many different causes for natural disasters; seismic activity, air pressure, ocean currents and soil erosion are the main causes. A natural disaster can cause damage to property, loss of life and effect the economy of the local area.
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  • Why is a pothole called a pothole?

    Q: Why is a pothole called a pothole?

    A: The word "pothole" can be split into two distinct morphemes. The first part being "pot," a word derived from Middle English that means "a deep hole," and the second part being "hole," which maintains the same meaning today, that is, a hollowness in the ground.
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  • What are the parts of a wave?

    Q: What are the parts of a wave?

    A: Transverse waves have two parts: a crest, which is the highest point of the wave, and the trough, which is the lowest part of the wave. Longitudinal waves also have two parts: compression, which are areas of high molecular density, and rarefactions, which are areas of low molecular density.
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  • Where is most of the freshwater found on earth?

    Q: Where is most of the freshwater found on earth?

    A: The majority of freshwater on earth is found in frozen glaciers and ice caps. This frozen water accounts for 68.7 percent of earth's freshwater, with 30.1 percent found in groundwater. Only 1.2 percent of fresh water is exposed to the surface of the planet.
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  • What are the two main types of glaciers?

    Q: What are the two main types of glaciers?

    A: The two main types of glaciers are continental glaciers and alpine glaciers. Continental glaciers are also known as ice sheets because their form and flow are not significantly affected by underlying geographic formations. Alpine glaciers form on mountains and flow down mountain valleys.
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  • What is deforestation?

    Q: What is deforestation?

    A: Deforestation is clearing away woodlands to use the cleared land for other uses. Deforestation happens to all types of woodland, including jungle and rain forest. The land is often used for farming or urban development.
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  • What is ecological balance?

    Q: What is ecological balance?

    A: Ecological balance is a theory stipulating that natural conditions, including numbers of various animal and plant species, remain stable on their own through variations over time. The theory, also known as balance of nature, also holds that natural equilibrium can be changed significantly by new species entering an ecosystem, the disappearance of some species, man-made changes to the environment or natural disasters.
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  • What are the main causes of flooding?

    Q: What are the main causes of flooding?

    A: Heavy, consistent and prolonged rainfall coupled with the overflowing of rivers and other water channels is one of the main causes of flooding. As rainwater reaches and fills the river channels, the water spreads on the floodplain or the land next to the river and causes flooding.
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  • What are types of natural calamities?

    Q: What are types of natural calamities?

    A: Types of natural calamities include hurricanes, earthquakes and tsunamis. Often, these calamities are connected such that one sets off another, as with earthquakes and tsunamis. Natural calamities are differentiated from human-made calamities, such as industrial accidents.
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  • Why are deserts hot in the day and cold at night?

    Q: Why are deserts hot in the day and cold at night?

    A: The heat that radiates from the sun and heats up the land begins to heat up the air and then escapes into the atmosphere due to the lack of clouds and humidity. This is the main reason that deserts can be hot during the day but cold during the night.
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  • What are some interesting facts about the Hubbard Glacier?

    Q: What are some interesting facts about the Hubbard Glacier?

    A: The Hubbard Glacier is the largest tidewater glacier in North America. A tidewater glacier is one that flows into the ocean. The glacier is approximately 7 miles wide at its foot and 76 miles long. These measurements are constantly changing as the Hubbard Glacier continues to grow and move forward.
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  • Why does a compass always point north?

    Q: Why does a compass always point north?

    A: The earth's magnetic field causes a compass to point north, as compasses are powered by magnets. The magnets inside compasses are drawn to the magnetic North Pole, which is about 1,000 miles south of the actual North Pole. Therefore, even though a compass always points north, it does not always point toward the true north.
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  • What is the composition of air?

    Q: What is the composition of air?

    A: Air is a gaseous substance that is composed primarily of nitrogen, oxygen and argon. The air in the atmosphere that surrounds the Earth is approximately 78 percent nitrogen, 21 percent oxygen and 1 percent argon, with the remainder made up of various other gases including neon, helium and hydrogen.
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