Chapter 16

Wind has the power to Move Turbines Move Sailboats Erode the land Dry land is eroded easily Moist land/heavier soil, more wind resistant

Sand 0.06mm to 2mm diameter Loose fragments of weathered rocks and minerals Quartz Mica Feldspar Magnetite Dust Less than 0.06mm diameter Microscopic fragments of rocks and minerals that come from soil and volcanic eruptions; plants animals and bacteria Fossil fuel burning and manufacturing processes produce dust.

Saltation – series of jumps and bounces; Sand moves in the direction the wind blows. Dust Can be carried high in the air, sometimes being suspended Volcanic dust can remain in the air for several years. Can create dust storms that cover many miles and block the sun for days.

Deflation – “to blow away” ; most common type of wind erosion Desert Pavement – remain gravel left behind forming surface of closely packed particles that help RESIST erosion

Deflation Hollow – Shallow depression remaining after the soil is gone

Ventifacts – Rocks that are smoothed by wind abrasion

Dunes – sand is blown to form mounds of sand

Fine dust deposited in layers Extremely fertile – great for growing grains Found in China Gobi Desert, Mongolia Central Europe Mid-Western States

Waves and currents are produced as WIND moves over the ocean and erodes the shorelines.

Boundary where the ocean and land meet Waves striking rock along the shoreline can produce seismic waves. Shorelines are temporary and unstable

Waves break off pieces of rock and throws them back against the shore. Abrasive action causes rock to become small pebbles and sand grains.

Salt Water and Air force into cracks of rock producing chemical reactions Large waves = Large amount of Erosion A SINGLE STORM Can drastically change the shoreline and the appearance.

Sea Cliffs Found where waves strike directly against rock. Waves slowly notch base of cliff, then cut under overhanging rock until it falls Gradually worn back and made steeper, some vertical Soft Rock – (sedimentary) erodes faster Hard Rock – (granite) erodes slowly Headland – resistant rock areas projecting out from shore. Bays are formed from an intermediate type rock

Sea cave – waves cut into rock that are weak and fractured causing a large hole or cave. Sea arch – enlarged sea cave that eventually cut completely through the headland. Sea stack – offshore columns of rock.

Wave-cut terrace – almost level platform left under water at the base of a sea cliff Wave-built terrace – eroded material is deposited a distance from shore that extends the wave-cut terrace Slow if in shallow water

Land feature from the deposit of sand or rock fragments. Form where the amount of sand/fragments moving toward the shore is greater than what is moving away. Type of sand – depends on the source of rock

Granite - lighter colored fragments of quartz and feldspar

Black Sand Oregon and Washington States have areas of black sand.

Contains shell and coral fragments

Berm – raised section of sand deposition on a beach most often used for recreation. Winter – large storm waves remove sand from the beach making it higher and steeper. Sand moved away is deposited off shore, forming long underwater ridge called a SANDBAR Summer – Sand is returned to widen the beach

The direction a wave approaches determines how it will move sand grains and other materials. Waves move at an angle to the shoreline Pushes water along shore Water moves Parallel to the shoreline

Long, narrow deposit of sand connected at one end to the shore May curve into a hook shape

Ridges of sand that connect an offshore island to the mainland.

Change in Sea Level Past Ice age caused sea levels to be ~140m LOWER Now Continental ice sheets have been melting and sea levels RISING ~1mm/yr If Antarctica and Greenland ice sheets melted sea levels would rise 60m. NY, Los Angeles, Miami, and Houston would be just a few of the cities endangered.

A coastline can be submerged or exposed. Lithosphere becoming lighter will cause it to rise, and sea levels to lower Lithosphere becoming heavier will cause it to sink, and sea levels to rise. Example: East coast is sinking (trailing edge of coastal plate) West coast is rising (N. California, Oregon, and Washington) in some areas and sinking in other areas (San Francisco Bay)

Formed when sea levels rise or the lithosphere sinks. (pg 308 in textbook) Beaches are short, narrow, and rocky May form offshore islands Irregular Coastlines (NE coast of the United States)

Mouth of a river valley submerged by ocean water. Becomes a wide shallow bay where salt water and fresh water mix. Important source of shrimp, crab, and oysters CHESAPEAKE BAY, VA

Flooded, U-shaped glacial valleys form narrow deep bays with steep walls. Coasts of Alaska, Chile, Greenland, Norway, and Western Canada.

When land rises or sea level falls Steep slope, exposed rapidly, erosion features (sea cliffs, narrow inlets, bays, & wave-cut terraces Most of West U.S. coast Much of Florida coast

Shoreline has moved inland as much as 150km Geologists believe has isolated former dunes from the old shoreline producing barrier islands. Long, narrow, offshore ridges of sand lying nearly parallel to shoreline. There are 300 barrier islands between Long Island, NY and Padre Island, TX

Draw these in your notebook.