ISCI Exam Three- Chapter 24/Earth's Surface- Land and Water

The salinity of seawater has remained about the same for millions of years- perhaps even a billion years. Why?

Salts are removed from seawater about as fast as they are deposited

Groundwater

Water that resides in a saturation zone.

Do you live in a watershed?

Yes, a watershed is the land that drains into a stream. The water where you live drains somewhere, so everyone lives in a watershed.

Aquifer

Zone of water-bearing rock through which groundwater can flow.

Identify and describe the three types of stress a rock may experience. Describe the three ways in which rock can respond to applied stresses.

a. Compressional stress is the pushing together of masses of rock, tensional stress is the pulling apart of rock, and shear stress is produced by rock blocks sliding past each other. b. Rock can break, deform elastically, or deform plastically

The ocean basin?

Is mostly flat but features mountains and trenches

Where are most of the world's volcanoes formed?

Most volcanoes are formed near plate boundaries. Volcanoes form where one plate subduct beneath another, triggering magma generation (convergent boundary), and where plates move away from one another (divergent boundaries).

Where are most of the volcanoes on earth located?

Most volcanoes are in the Ring of fire in the Pacific Ocean.

Divide

Imaginary line that is the highest ground separating two drainage basins.

What is earth's highest point? How high is it? What is earth's lowest point? How deep is it?

Mount Everest (8,848 meters or 29,028 ft above sea level) Mariana Trench (Depth of 11,033 m/ 36,198 ft)

Approximately what percentage of Earth's liquid water is fresh water?

50%

Upwarped mountain

A dome-shaped mountain produced by a broad arching of earth's crust.

Suppose huge blocks or crust drop down along normal faults. Between them, a block is left standing and over time it is uplifted to great heights. What kind of mountain is this?

A fault-block mountain

Stress

A force applied to rock

Fault

A fracture through a rock along which sections of the rock have moved.

Volcano

A hill or mountain formed by the extrusion of lava, ash, and rock fragments.

Fold

A layer or layers of bent (plastically) rock.

Glacier

A mass of dense ice that forms when snow on land is subjected to pressure from overlying snow, so that its compacted and recrystallized.

Folded mountain

A mountain that features extensive folding of rock layers.

Fault-block mountain

A mountain that forms from tension and that has at least one side bounded by a normal fault.

How do hot spots produce mountains?

A seamount is formed by lava (an undersea volcanic peak) and if the seamount gets big enough it will poke above the ocean as a volcanic island. -Plates move so that eventually a volcanic island loses its position over a hot spot. -Because of this the volcano will eventually lose its source of magma and become extinct. -Over time, a new volcanic island can grow over the hot spot, and if it does a series of mountainous volcanic islands develop.

Hot spot

A stationary, hot region deep in earths interior, usually originating near the mantle-core boundary.

Some people "fold" under stress. Other "crack up." How is this like what happens to rock?

A stress is an applied force. A rock "cracks up" (breaks) or folds when the stress is sufficient.

Infiltration

Absorption of water by the ground.

Seamount

An undersea volcanic peak

List five major landforms in the United States, and describe them in as much geologic detail as you can.

Answers will vary. Some major landforms are the Mississippi Delta, the Black Hills, San Andreas Fault, the Great Plains, the Appalachian Mountains and the Grand Canyon.

Fault-block mountains?

Arise from the stretching of Earth's crust

Name one biological water pollutant, one physical water pollutant, and one chemical water pollutant.

Biological:Pathogens in untreated sewage and animal feces washed into water, remains of plant material Chemical: Heavy metals; arsenic and mercury, paint thinner and motor oil Physical: Heat, soil, litter, fishing nets and plastic objects such as six-pack rings

When a rock deforms plastically, it?

Changes its size or shape permanently

Where would you expect to see more runoff- along a city street or in a prairie meadow? Why?

City streets, because the rain water turned to runoff depends on the type of soil and how wet or dry it is. As the pavement of city streets reduces the grounds ability to soak up water, the runoff is greater on city streets.

What percentage of the earth is covered with ocean?

Cover 70% of Earth

Residence time

The length of time water exists in a reservoir.

Why does a series of islands develop over a hot spot?

The motion of the plates carries crust over a hot spot so that, over time, a chin of volcanoes may develop there.

Porosity

The percentage of the volume of a rock or sediment that consists of open space.

Reservoir

Each of the places where water is stored as it moves through the water cycle

Which process in the water cycle requires enormous energy input from the sun?

Evaporation

Name four types of mountains, classified by common structural features. Give an example of each of the four types of mountains.

Folded mountains: The Appalachians, Rockies, and Himalayas. Upwarped mountains: Black Hills of South Dakota, and the Adirondack mountains. Fault block mountains: Tetons in Wyoming, and Sierra Nevada in California Volcanic mountains: Mauna Loa, Mt. Fuji, and Sunset Crater.

Underground water in the saturation zone is called?

Groundwater

A section of crust is compressed as its pushed upward by forces acting on it from below. If the rock bends and arches upward to from a dome in response to this stress, what type of mountain will result? What kind of mountain will result if the rock breaks and moves upward along fault lines?

-An upwarped mountain -A fault-block mountain

Where is most of earth's water? What percentage of it resides there? Where is most of earths fresh water?

-Most of earth's water (97.6%) is in the oceans. -Most of earth's freshwater is in ice caps and glaciers.

What is the difference between a plain and a plateau?

-Plateaus are flat areas elevated more than 600 m above sea level. -Plains are broad, flat areas that don't rise far about sea level.

Which surface features record tectonic compression acting on rock? Which features show tectonic tension?

-Tectonic pressures take place at convergent plate boundaries when the two tectonic plates are colliding into one another. -Tectonic tension is one form of stress. It occurs at diverging plate boundaries when the two tectonic plates pull away from each other.

Why are faults important?

-they are the usual locations of earthquakes -they control the movement of groundwater -they control the subsurface accumulations of fossil fuels

The ogallala Aquifer

-underlies several states -is being pumped at a high rate -is a source of fresh water

The soil under Samantha's home is rich in clay. The ground therefore has high porosity but low permeability. Would Samantha be able to build a good well in her backyard? Why or why not?

No, because the ground has high porosity and low permeability makes them poor acquirers. The aquifer with high porosity and high permeability are good sources of fresh groundwater. So the flow of water will be very slow for low permeability grounds.

What is the difference between point and non point pollution? Which is easier to control? Why?

Point pollution: Pollution due to a specific source. EX: Oil tanker that spills oil into ocean, or gas station that leaks chemicals into groundwater. Non point pollution: Does not come from a single source. EX: Comes from homes, farms, freeways, city streets. -Point pollution is easier to control because it comes from one specific location and not many different sources.

Runoff

Precipitation not absorbed by the ground that moves over earth's surface.

Snow becomes glacial ice when it is subjected to?

Pressure

Name three kinds of faults and distinguish among them.

Reverse fault: the hanging wall and footwall are pushed together resulting in the hanging wall being pushed above the footwall. In a normal fault: rocks in the hanging wall and footwall are pulled apart The rocks in the hanging wall drop down relative to to the rocks in the footwall. Strike-slip fault: rock masses have side to side motion with respect to one another with no vertical displacement.

What are the three different types of volcanoes?

Shield Volcanoes: Volcanoes built up from a steady supply of fluid basaltic lava. Cinder Cones: Volcanoes that are very steep but rarely rise higher than 300 meters above ground level. Composite Cone or Stratovolcano: Volcano with a high, steep-sided summit and gently sloping fanks built of alternating layers of lava, ash, and mud. EX: Mount St. Helens in Washington

The Sierra Nevada Range of California features fault-block mountains. Were these mountains produced by compressive or tensional forces?

Tensional Forces

Watershed

The area of land that drains into a stream.

Hydrologic cycle

The cycle of evaporation and precipitation that controls the distribution of earths water.

Ocean basin

The deep portion of the sea floor between continental margins and the mid ocean ridge.

Permeability

The ease with which fluids flow through the pore spaces in sediments and rocks

Abyssal plains

The flat regions of the ocean basin.

Describe the three parts of a passive continental margin. Describe the parts of an active continental margin.

The three parts of a passive continental margin are: 1. The continental shelf: an underwater extension of the continent. 2. The continental slope: a steep, narrow boundary between continental and oceanic crust. 3. Continental rise: a mound of sediment built up at the base of the continental slope. -An active continental margin consists of a continental slope and an accretionary wedge, a mass of continental crust donated to the overlying plate by the descending plate.

Water table

The upper boundary of the saturated zone.

What are the two different kinds of continental margins? How do they differ?

There are active and passive continental margins. -Active margins are sights of plate boundaries, and passive margins are located away from plate boundaries. Their structural features vary as well. -For example, the continental shelf along a passive margin typically has a gradual slope. An active margin often features an ocean trench with an accretionary wedge.

Continental margin

Transition zone between dry land and the deep ocean bottom.