EARTH SYSTEMS 2 ND SEMESTER FINAL EXAM REVIEW

EARTH SYSTEMS 2 ND SEMESTER FINAL EXAM REVIEW GUIDE 2012 -2013

What events warn scientists that a volcanic eruption may occur?

1. ) changes in earthquake activity near or around the volcano such as an increase in the strength and frequency of the earthquakes 2. ) temperature changes in the rock and soil surrounding a volcano 3. ) the upward movement of magma beneath the surface may cause the surface of the volcano to bulge outward 4. ) changes in the amount and composition of the gases that the volcano emits

What are three primary topographical land tectonic settings?

1. ) convergent/divergent tectonic plates 2. ) subduction zones -trench -island arc 3. )mid-ocean ridge

What is the difference between a pluton and a batholith?

Magma that pushes up can cause fissures or fractures that can be skinny lines or huge fat formations. Magma that does not reach the Earth’s surface, then cools and solidifies is called a pluton. Small plutons are dikes, and large plutons are batholiths. What is an example of a batholith in Georgia?

What is an example of an exposed batholith?

Stone Mountain

Where is the most active site of volcano and tectonic activity on Earth?

Pacific Ring of Fire

What are the fragments of rock that are spit from a volcano and includes large and small pieces of volcanic ash, dust, lapilla, bombs, and blocks?

pyroclastic material

How are most volcanic islands formed?

Most island volcanoes are made or formed of mafic magma. Because of the magma’s low viscosity, they are the result of quiet eruptions. Mafic magma is magma rich in magnesium and iron and is commonly dark in color. Felsic magma is made of lightcolored silica materials. Mafic rock commonly makes up oceanic crust and felsic and mafic rock together usually make up continental crust.

What are the conditions that affect whether magma forms?

Magma forms when the temperature of the rock rises above the melting point of the minerals that compose it. Also, the pressure of the rock lessons or decreases faster than its temperature does. And, when it is mixed with fluids that decrease it’s melting point.

What happens when an ocean plate and a continental plate collide?

The oceanic plate is likely to subduct because it is more dense than the continental plate.

What causes rock in the lower mantle to remain below its melting point?

Both temperature and pressure increase as depth below Earth’s surface increases. This keeps rock at the core hot and liquid.

Explain how magma reaches Earth’s surface.

Both temperature and pressure increase as depth below Earth’s surface increases. This keeps rock at the core hot and liquid.

How does the amount of a rock’s surface area affect weathering?

The larger the area, the higher the rate of weathering.

Plant and animal activities cause what kind of weathering?

chemical and mechanical Weathering Chemical weathering is when rocks break down as a result of chemical reactions such as the formation of caves or iron rusting. Mechanical weathering is when rocks break down by physical means such as freezing and thawing and salt wedging.

Climates that have the fastest rate of weathering are what?

Alternating hot and cold temperatures

Topography with high mountains and steep slopes are especially vulnerable to what type of weathering?

mechanical weathering

Which landform is NOT the result of weathering and erosion?

wetlands

Which farming methods conserve or save soil?

• Contour plowing – plowing the land in contours or curves that follow the shape of the land preventing water from flowing down hill and causing gullies to form • Strip-cropping – alternating cover crops side by side with food crops preventing runoff • Terracing – constructing step-like ridges that follow the contours of the land preventing runoff • Crop rotation – the planting of different crops each year preventing the depletion of nutrients the soil needs to be healthy for plants Furrowing is does not help soil. It is the old fashioned way of using a tool like a plow to dig a trench.

What effect would you expect a drought to have on the capillary action in soil and, ultimately, on your supply of fresh groundwater?

Without rainwater to replenish aquifers, the capillary action will slow and then stop as the water table drops and then dries. The result is a dry well and no water. Conservation of groundwater is critical during times of drought in order to prevent total depletion of the water supply.

How does gravity affect the flow of groundwater?

Water flows downward in response to gravity. The rate at which it flows depends on the permeability of the rock and the gradient. The greater the permeability of the rock, the faster the water will flow. The velocity of the flow responds to gravity and increases as the gradient increases.

Rock becomes chemically weathered when what happens?

When carbonic acid, formed when water passes through soil, dissolves minerals in the rock, then rock becomes chemically weathered?

Which minerals make rocks especially vulnerable to chemical weathering?

calcite • The mineral calcite is composed of calcium, carbon, and oxygen. The chemical formula is Ca. CO 3.

A cavern is a natural cavity in rock that forms as a result of what?

the dissolution of minerals or minerals washed out from inside the Earth

How does a river form?

• Precipitation or rainfall exceeds evapotranspiration. • Soil soaks up as much water as it can hold. • Excess water erodes the land, and eventually a river valley forms.

What are two ways that fresh water supplies can be maintained?

• water conservation methods • alternative methods of obtaining fresh water

What is a watershed?

the area drained by a river system

What is a tributary?

a stream that feeds another stream or lake

Where does most evaporation and precipitation occur on Earth?

oceans

What are the stages of the water cycle?

The process by which liquid water changes into water vapor is called evaporation. Annually, about 500, 000 km 3 of water evaporates into the atmosphere. The total loss of water from the soil, water sources such as lakes, rivers, oceans, streams, plants, and organisms is called evapotranspiration. Then, when water changes states from a gas to a liquid and cools, condensation occurs and some of it becomes tiny water droplets and forms clouds. Finally, in the last stage of the water cycle called precipitation, water falls to Earth in the form of rain, snow, sleet, or hail and the process starts over. More than 75% of all precipitation falls on Earth’s oceans.

A massive sheet of ice that may cover millions of square kilometers is what?

continental glacier

What is an alpine glacier?

An alpine glacier is a narrow, wedge-shaped piece of ice that forms in mountainous regions and is confined to small areas by surrounding topography. Examples include valley glaciers, cirque glaciers, and piedmont glaciers.

Sediment carried and deposited by glaciers is called what?

Glacial drift

Explain the principle behind the Milankovitch theory?

Cyclical changes in Earth’s orbit and in the tilt of its axis cause climatic changes.

Which of the following is one theory that explains the cause of ice ages?

Ice ages may be caused by volcanic dust that blocks sunlight.

How does an alpine glacier form and where is it found?

It forms in the mountains and is confined by local topography.

How does an iceberg form?

Action of the tides causes a block of ice to break from an ice shelf.

What forms when small marine animals that live in warm, shallow seas grow?

coral reefs

A gentle slope that forms a smooth coastal plain with long, wide beaches is a feature of which of the following?

emergent coastline

An area where fresh water from rivers mixes with salt water from the ocean is known as what?

estuary

How are barrier islands formed?

Barrier islands are formed when sand spits separate from land after a storm. Sarasota, Florida

How can coastal lands be protected?

• Private owners and the government need to work together to form new protective laws • We need to vote for people who will work now to form guidelines to protect the coastlines. • We can encourage local governments to work to rebuild eroded beaches. • Local governments should be encouraged to slow or stop coastal development or putting up new buildings close to the beach.

Where are the flattest regions on Earth?

abyssal plains are large, flat, almost level areas of deep-ocean basins

How do sediments from rivers spread over the deepocean basins?

turbidity currents Turbidity currents are formed when earthquakes cause underwater landslides or when a large sediment load is shifted from other currents and runs down a continental slope.

The Mariana Trench is best known for its what?

The Mariana Trench is known as the deepest part of the ocean on Earth. The trench is about 2, 550 kilometers (1, 580 mi) long but has a mean width of only 69 kilometers (43 mi). It reaches a maximum-known depth of about 10. 91 kilometers (6. 78 mi) (35, 800 ft) at the Challenger Deep, a small slot-shaped valley in its floor, at its southern end, although some unrepeated measurements place the deepest portion at 11. 03 kilometers (6. 85 mi). James Cameron and his team is currently diving in the Mariana Trench.

What are ocean trenches and midocean ridges and how do the processes that form them differ?

Trenches are long, narrow depressions or holes in deep-ocean basins and form where one tectonic plate subducts under another tectonic plate.

Mid-ocean ridges are long undersea mountain chains with steep, narrow valleys and form as magma rises from the asthenosphere.

What are the two main processes that ocean water temperature depends on?

• The oceans’ temperature depends on the solar energy an area receives. • It also depends on the movement of water through the rotation of the Earth, through the pull of gravity from the Moon, and convection currents.

Volcanic eruptions, chemical weathering of rock on land, and chemical reactions between sea water and newly formed sea-floor rocks provide most of the raw elements that form this dissolved solid in the ocean.

sea salts Sea salts are made of about 75 dissolved chemical elements. The most abundant elements in ocean water consist of chlorine, sodium, magnesium, sulfur, calcium, and potassium. Gold, zinc, and phosphorus are some of the trace elements found in ocean water.

The ocean zone that receives the most solar energy and is home to the most diverse ocean life forms is what?

pelagic zone

Why are plankton the foundation of life in the ocean?

they form the base of the ocean food chain

The warming of the surface and lower atmosphere of Earth that occurs when carbon dioxide, water vapor, and other gases in the air absorb and reradiate infrared radiation is known as what?

greenhouse effect

Prevailing winds that blow throughout the contiguous United States are called what?

Westerlies

What’s the difference between an air mass and a weather front?

• An air mass is a body of air. It has similar characteristics to the land on top of which it forms. If there is a low pressure, there is most likely to be a storm. • Fronts are the boundaries in between two different, or same air masses. (e. g: a cold front is when a cold air mass hits a warm air mass and quickly pushes the warm air mass upward. )

Continental polar, maritime polar, continental tropical, and maritime tropical are types of what?

air masses Air masses are large bodies of air throughout which the temperature and moisture content are similar.

What is the weather effect that occurs when a moving air mass hits a mountain, rises, cools, and loses most of its moisture and precipitation?

Rainshadow Effect

What affects the angle at which the sun’s rays hit the Earth?

Latitude Lines of latitude run east and west. The only line of latitude that is a Great Circle is the equator.

What are the two main factors used to study climates?

Temperature and Precipitation

What happens when city buildings reradiate solar energy?

A heat island forms.

Does land or water hold the most heat and why?

Land holds more heat than water. Land is stationary. Water moves around.

How did the oceans become salty?

Solids dissolved on land ran into oceans.

Where is the majority of the matter from the solar nebula found?

The Sun

What are the planets in our solar system?

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (My very educated mother just served us nine pizzas. ) Pluto is considered a dwarf planet.

What are the major characteristics of the inner and outer planets?

The inner planets are made of solids and the outer planets are made of gas and are called gas giants.

What are Johannes Kepler’s laws of planetary motion?

Kepler’s first law is the law of ellipses that states each planet orbits the sun in an ellipse which is a closed curve with the focus point being the sun.

Kepler’s second law is the law of equal areas which describes the speed at which objects travel at different points in their orbits.

Kepler’s third law is the law of periods which describes the average distance of a planet from the sun and the orbital period of the planet. The orbital period is the time it takes for a body to complete a single orbit.

What is a solar nebula?

A solar nebula is a rotating cloud of gas and dust.

How did the atmosphere of Earth develop?

Scientists believe the atmosphere formed when volcanic eruptions released large amounts of gases in a process called outgassing.

What separates the inner and outer planets of our solar system?

The asteroid belt separates the inner and outer planets in our solar system.

ESSAY QUESTION: Explain what the five types of land degradation are and how they affect the Earth.

Land Degradation – when human activity and natural processes damage the land to the point where it no longer supports the local ecosystem which includes all the animals and plants · agriculture – the process where arable land is plowed, fertilize, irrigated, and all natural ecosystems are destroyed · urbanization – the movement of people from rural areas to cities causing urban sprawl when fertile, arable land is covered over with buildings and cement · cvergrazing – when more animals graze on a piece of land than the land can support which destroys all grasses and causes erosion · deforestation – the clear-cutting of all trees destroying all animals habitats · desertification – when an area becomes like a desert because all the plants are removed and the land is useless for farming or human habitation