Ch 6 NotesMapping Earth’s

Surface.

What are the three main types of landforms?

• Plain—a landform made up of nearly flat or gently rolling land with low relief.

• Mountain—a landform with high elevation and high relief. (Mountain range is a group of mountains closely related in shape, structure, and age)

• Plateau—a landform that has a high elevation and a level surface.

What is the Equator and Prime Meridian?

• Equator is and prime meridian are the baselines for measuring distances on Earth’s surface.

• Equator is an imaginary line that circles the Earth halfway between the North and South poles.

• Prime Meridian is an imaginary line that circles the Earth through the North and South Pole and passes through Greenwich, England.

Picture of Equator and Prime Meridian.

What are hemispheres?

• Hemisphere is one half of the sphere that makes up Earth’s surface.

• The equator divides the Earth into a northern and southern hemisphere.

• The prime meridian divides the Earth into an eastern and western hemisphere.

Picture of Hemispheres

• Northern & Southern • Eastern & Western

How do we locate points on Earth’s surface?

• The lines of latitude and longitude form a grid that can be used to find locations anywhere on Earth.

• Latitude is the distance in degrees north or south of the equator (thus the equator is the starting point for latitude).

• Longitude is the distance in degrees east or west of the prime meridian (thus the prime meridian is the starting point for longitude).

What are the three types of map projections?

• There are three types of map projections; mercator projection, equal-area projection, and conic projection.

• Mercator—all latitude and longitude lines appear as straight lines and form rectangles (size and shape of landmasses near equator are distorted and can not show poles).

• Equal-area—correctly shows the relative sizes of Earth’s landmasses (shapes of landmasses near the edge of map appear stretched and curved).

• Conic—lines of longitude appear as straight lines while lines of latitude are curved (little distortion on maps but can only be used for small areas).

Mercator Maps

Equal-Area Maps

Conic Maps

How are computers used in mapping?

• With computers, mapmakers can store, process, and display map data electronically.

• Satellite images are pictures of the Earth’s surface based on information collected by satellites.

• Global Positioning System (GPS) is a method of finding latitude, longitude, and elevation points on Earth’s surface using a network of satellites.

What are topographic maps?

• A topographic map is a map showing the surface features of an area.

• Topographic maps use contour lines to represent elevation, relief, and slop on topographic maps.

• Contour lines connect points of equal elevation.• Contour interval is the change in elevation from

contour line to contour line.• Index contours are labeled with elevations in

units; such as 1600 or 2000.

Picture of Topographic Map

What is weathering and erosion?

• Weathering and erosion work together continuously to wear down and carry away the rock’s at Earth’s surface.

• Mechanical weathering includes freezing and thawing, release of pressure, plant growth, action of animals, and abrasion.

• Chemical weathering includes the action of water, oxygen, carbon dioxide, living organisms, and acid rain.

What factor affect the rate of weathering?

• Several factors affect the rate of weathering.– Type of rock (permeability increases the

weathering rate)– Climate

• Temperature (higher temps result in faster weathering)

• Rainfall (weathering increases in wet climates)

Picture of weathered objects.

• Unweathered headstone.

• Weathered headstone.

How does soil form?

• Soil forms as rock is broken down by weathering and mixes with other materials on the surface. Soil is constantly being formed wherever bedrock is exposed.

• Soil is a mixture of rock particles, minerals, decayed organic matter (DOM or humus), water, and air.

What are the soil types?

• Scientists classify the different types of soil into major groups based on climate, plants, and soil composition.

• Soil types are;– Tundra soils −Southern forest

soils– Northern forest soils −Desert soils– Prairie soils −Tropical soils– Mountain soils

How are soil particles classified?

• Soil particles are classified based on their sizes.– Clay is less than 1/256 mm– Silt is between 1/256 and 1/16 mm– Sand is between 1/16 and 2 mm– Gravel is greater than 2 mm.