Chapter 3Section 1- Finding Locations on EarthSection 2- Mapping Earth’s SurfaceSection 3- Types of Maps

Section 1- Finding Locations on EarthObjectives:1. Distinguish between latitude and longitude.2. Explain how latitude and longitude can be used to

locate places on Earth.3. Explain how a magnetic compass can be used to find

directions on Earth’s surface.

Introduction Earth is not a perfect sphere Earth has an axis

Latitude What is latitude? What are Parallels?

Latitude- Degrees of Latitude Measured in Degrees Actual Distance of 1° latitude is 111km The equator is designated 0° latitude The distance between the equator to either pole is ¼ of a circle Circle

360° Parallels North of the Equator are labeled:

N (North) Parallels South of the Equator are labeled:

S (South)

Latitude- Minutes and Seconds Each degree of latitude consists of 60 equal parts

Called minutes Each minute can be divided into 60 equal parts

Called seconds This allows for a more precise location

Longitude What is Longitude? What is Meridian?

Longitude- Degree of Longitude Circle 360°

Prime Meridian is at 0° Passes through Greenwich, England

Meridian opposite of the Prime Meridian is 180° Locations East of the Prime Meridian are labeled:

E (East) Locations West of the Prime Meridian are labeled:

W (West)

Longitude- Distance Between Meridians Measured in Degrees The actual distance between two longitudes is 111km All Meridians meet at the Poles

The distance measured by a degree of longitude ↓as you move from the equator toward the poles

Great Circles Often used for navigation A great circle is any circle that divides the globe in

halves, or marks the circumference of the globe

Finding Direction Magnetic Compass Geomagnetic Poles

Located in a different place than the geographical poles

Finding Direction- Magnetic Declination The angle between the direction of the geographic pole

and the direction in which the compass needle points Has been determined for points all over Earth Because the Earth’s magnetic field is constantly

changing, the magnetic declination around the globe also changes constantly

Locating geographic north is important in navigation and in mapmaking

Finding Direction- The Global Positioning GPS First GPS was launched in 1978 It calculates

Latitude Longitude Altitude

Section 2- Mapping Earth’s Surface Objectives:

1. Explain two ways that scientist get data to make maps.2. Describe the characteristics and uses of three types of

map projections.3. Summarize how to use keys, legends, and scales to read

maps.

Introduction What is the purpose of a globe? Why do we have types of maps?

How Scientist Make Maps Cartography (Cartographers)

Field surveys Take measurements of an area

Remote sensing

Map Projections A map is a flat representation of Earth’s curved surface

Distortion Size Shape Distance Direction

Map Projection A flat map that represent the three-dimensional curved

surface of a globe

Map Projections Cylindrical Projection Azimuthal Projection Conic Projection

Cylindrical Projection

Azimuthal Projection

Conic Projection

Reading a Map Direction on a Map Symbols Map Scales Isograms

Reading a Map- Map Legend

Reading a Map- Map Scale

Section 3- Types of Maps Objectives

1. Explain how elevation and topography are shown on a map

2. Describe three types of information shown in geologic maps

3. Identify two uses of soil maps

Introduction Earth scientists use a wide variety of maps that show

many distinct characteristic of an area. Some of these characteristics include:

Types of rocks Differences in air pressure Varying depths of groundwater in a region

Scientist also use maps to show: Locations Elevations Surface features of Earth.

Topographic Maps Most widely used Show the surface features

Natural features Rivers and hills

Constructed features Buildings and roads

Shows the elevation Height about sea level

Topographic Maps- Advantages Provides more detailed information about the surface Shows

Size Shape Elevation

Topographic Maps- Elevation Contour Lines

Show elevation Each contour line is an isogram that connects points that have the same

elevation The shape of the contour lines reflects the shape of the land

Contour Interval The difference in elevation between one contour line and the next

Relief The difference in elevation between the highest and lowest points of the area

being mapped Index Contours

Bold lines that are labeled by elevation

Topographic Maps- Landforms Contour lines spaced widely apart

Indicate the change in elevation is gradual Contour lines spaced closely together

Indicate the change in elevation is rapid and that the slope is steep Contour line that is a “V” shape

Indicates a valley If a river or stream flows through the valley the “v” will point upstream The width of the “v” indicates the width of the valley

Contour lines that form a closed loop indicates a hilltop or a depression

Topographic Maps- Map Symbols Color

The type of feature Constructed features are black

Buildings, boundaries, road or railroads Major highways are red Bodies of water are blue Forested areas are green Contour lines are black or brown Areas not verified are purple

Topographic Maps

Geologic Maps Designed to show the distribution of geologic features Created on top of another map this called a Base Map

Geologic Maps- Rock Units and Other Structures Geologic Unit

A volume of rock of a given age range and rock type Distinguished by color

Units of similar ages are generally assigned colors in the same color family Different shades of blue

Other Markings Contact lines- indicates places at which two geological

units meet called contacts

Soil Maps- Soil Surveys and Uses Used to classify, map, and describe soils Soil Surveys

Consists of 3 main parts Text, maps, and tables

Use of Soil Maps Valuable tools for agriculture and land management

Other Types of Maps Earth scientist also use maps to show the location and

flow of both water and air These maps are commonly constructed by plotting

data from various points around a region and then using isograms to connect the points whose data are identical

Questions

?’s