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Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation TransparenciesStandardized Test Prep Visual Concepts Resources Brain Food Video Quiz
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Models of the Earth Chapter 3 Table of Contents Section 1 Finding Locations on Earth Section 2 Mapping Earth’s Surface Section 3 Types of Maps
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Objectives Distinguish between latitude and longitude. Explain how latitude and longitude can be used to locate places on Earth’s surface. Explain how a magnetic compass can be used to find directions on Earth’s surface.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Latitude The points at which Earth’s axis of rotation intersects Earth’s surface are used as reference points for defining direction. These points are the geographic North Pole and South Pole. Halfway between the poles, a circle called the equator divides Earth into the North and Southern Hemispheres. A reference grid that is made up of additional circles is used to locate places on Earth‘s surface.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Latitude, continued One set of circles describes positions north and south of the equator. These circles are known as parallels, and they express latitude. parallel any circle that runs east and west around Earth and tat is parallel to the equator; a line of latitude latitude the angular distance north or south from the equator; expressed in degrees
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Latitude, continued The diagram below shows Earth’s parallels.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Latitude, continued Degrees of Latitude Latitude is measured in degrees, and the equator is 0° latitude. The latitude of both the North Pole and the South Pole is 90°. In actual distance, 1° latitude equals about 111 km. Minutes and Seconds Each degree of latitude consists of 60 equal parts, called minutes. One minute (symbol: °) of latitude equals 1.85 km. In turn, each minute is divided into 60 equal parts, called seconds (symbol: °).
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Longitude, continued East-west locations are established by using meridians. meridian any semicircle that runs north and south around Earth from the geographic North Pole to the geographic South Pole; a line of longitude longitude the angular distance east or west from the prime meridian; expressed in degrees
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Longitude, continued The diagram below shows Earth’s meridians.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Longitude, continued Degrees of Longitude The meridian that passes through Greenwich, England is called the prime meridian. This meridian represents 0° longitude. The meridian opposite the prime meridian, halfway around the world, is labeled 180°, and is called the International Date Line. Distance Between Meridians The distance covered by a degree of longitude depends on where the degree is measured. The distance measured by a degree of longitude decreases as you move from the equator toward the poles.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 3 Comparing Latitude and Longitude Section 1 Finding Locations on Earth
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Great Circles A great circle is any circle that divides the globe into halves, or marks the circumference of the globe. Any circle formed by two meridians of longitude that are directly across the globe from each other is a great circle. The equator is the only line of latitude that is a great circle. The route along a great circle is the shortest distance between two points on a sphere. As a result, great circles are commonly used in navigation, such as for air and sea routes.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Great Circles, continued The diagram below shows what a great circle is.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Great Circles, continued Reading Check Why is the equator the only parallel that is a great circle?
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Great Circles, continued Reading Check Why is the equator the only parallel that is a great circle? because the equator is the only parallel that divides Earth into halves
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Finding Direction One way to find direction on Earth is to use a magnetic compass. A magnetic compass can indicate direction because Earth has magnetic properties as if a powerful bar-shaped magnet were buried at Earth’s center at an angle to Earth’s axis of rotation. The areas on Earth’s surface just above where the poles of the imaginary magnet would be are called the geomagnetic poles. The geomagnetic poles and the geographic poles are located in different places.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Finding Direction, continued Magnetic Declination The angle between the direction of the geographic pole and the direction in which the compass needle points is called magnetic declination. In the Northern Hemisphere, magnetic declination is measured in degrees east or west of the geographic North Pole. Because Earth’s magnetic field is constantly changing, the magnetic declinations of locations around the globe also change constantly. By using magnetic declination, a person can use a compass to determine geographic north for any place on Earth.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Finding Direction, continued The diagram below shows the magnetic declination of the United States.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Finding Locations on Earth Chapter 3 Finding Direction, continued The Global Positioning System Another way people can find their location on Earth is by using the global positioning system, or GPS. GPS is a satellite navigation system that is based on a global network of 24 satellites that transmit radio signals to Earth’s surface. A GPS receiver held by a person on the ground receives signals from three satellites to calculate the latitude, longitude, and altitude of the receiver on Earth.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Objectives Explain two ways that scientists get data to make maps. Describe the characteristics and uses of three types of map projections. Summarize how to use keys, legends, and scales to read maps.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 How Scientists Make Maps Because most globes are too small to show details of Earth’s surface, such as streams and highways, a great variety of maps have been developed for studying and displaying detailed information about Earth. The science of making maps is called cartography. Scientists who make maps are called cartographers. Cartographers use data from a variety of sources, such as from field surveys and remote sensing. remote sensing the process of gathering and analyzing information about an object without physically being in touch with the object
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections A map is a flat representation of Earth’s curved surface. Transferring a curved surface to a flat map results in a distorted image of the curved surface. An area shown on a map may be distorted in size, shape, distance, or direction. Over the years, cartographers have developed several ways to transfer the curved surface of Earth onto flat maps. These methods are called map projections. map projection a flat map that represents a spherical surface No map projection is entirely accurate, but each kind of projection has advantages and disadvantages.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued Cylindrical Projections If you wrapped a cylinder of paper around a lighted globe and traced the outlines of continents, oceans, parallels, and meridians, a cylindrical projection would result. A cylindrical projection is accurate near the equator but distorts distances and sizes near the poles. One advantage to cylindrical projections is that parallels and meridians form a grid, which makes locating positions easier. On a cylindrical projection, shapes of small areas are usually well preserved.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued The diagram below shows a cylindrical projection.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued Reading Check Why do meridians and parallels appear as a grid when shown on a cylindrical projection?
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued Reading Check Why do meridians and parallels appear as a grid when shown on a cylindrical projection? Because both the parallels and the meridians are equally spaced straight lines on a cylindrical projection, the parallels and meridians form a grid.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued Azimuthal Projections A projection made by placing a sheet of paper against a globe such that the paper touches the globe at only one point is called an azimuthal projection. On an azimuthal projection, little distortion occurs at a the point of contact, but the unequal spacing between parallels causes a distortion in both direction and distance that increases as distance from the point of contact increases. One advantage of azimuthal projections is that on these maps, great circles appear as straight lines. Thus, azimuthal projections are useful for plotting navigational paths.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued The diagram below shows an azimuthal projection.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued Conic Projections A projection made by placing a paper cone over a lighted globe so that the axis of the cone aligns with the axis of the globe is known as a conic projection. Areas near the parallel where the cone and the globe are in contact are distorted least. A series of conic projections can be used to increase accuracy by mapping a number of neighboring areas and fitting the adjoining areas together to make a polyconic projection. On a polyconic projection, the relative sizes and shapes of small areas on the map are nearly the same as those on the globe.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Map Projections, continued The diagram below shows a conic projection.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map Maps provide information through the use of symbols. Direction on a Map Maps are commonly drawn with north at the top, east at the right, west at the left, and south at the bottom. Some maps use parallels of latitude and meridians of longitude to indicate direction and location. Many maps also include a compass rose, which is a symbol that indicates the cardinal directions (north, east, south, and west), or an arrow that indicates north.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map, continued Symbols Symbols are commonly used on maps to represent features such as cities, highways, rivers, and other points of interest. Symbols may resemble the features that they represent, or they may be more abstract. Symbols are commonly explained in a legend. legend a list of map symbols and their meanings
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 3 Information on Maps Section 2 Mapping Earth’s Surface
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map, continued Map Scales scale the relationship between the distance shown on a map and the actual distance Map scales are commonly expressed as graphic scales, fractional scales, or verbal scales. A graphic scale is a printed line that has markings that represent units of measure, such as meters or kilometers. A fractional scale is a ratio that indicates how distance on Earth relates to distance on the map. A verbal scale expresses scale in sentence form.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map, continued Reading Check Name three ways to express scale on a map.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map, continued Reading Check Name three ways to express scale on a map. by using a graphic scale, or a printed line divided into proportional parts that represent units of measure; a fractional scale, in which a ratio shows how distance on Earth relates to distance on a map; or a verbal scale, which expresses scale in sentence form
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Mapping Earth’s Surface Chapter 3 Reading a Map, continued Isograms isogram a line on a map that represents a constant or equal value of a given quantity The second part of the word, -gram, can be changed to describe the measurement being graphed. For example, when the line connects points of equal temperature the line is called an isotherm. When the line connects points of equal atmospheric pressure, the line is called an isobar. Isograms can be used to plot many types of data, such as atmospheric pressure, temperature, precipitation, gravity, magnetism, density, elevation, chemical composition, and many others.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Objectives Explain how elevation and topography are shown on a map. Describe three types of information shown in geologic maps. Identify two uses of soil maps.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps One of the most widely used maps is called a topographic map, which shows the surface features of Earth. topography the size and shape of the land surface features of a region elevation the height of an object above sea level Advantages of Topographic Maps Topographic maps provide more detailed information about the surface of Earth than either drawins or.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Elevation on Topographic Maps On topographic maps, elevation is shown by using contour lines. contour line a line that connects points of equal elevation on a map The difference in elevation between one contour line and the next is called the contour interval. The contour interval is selected based on the relief of the area being mapped. relief the difference between the highest and lowest elevations in a given area Every fifth contour line is darker than the four lines one either side of it. This index contour makes reading elevation easier.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Landforms on Topographic Maps The spacing and direction of contour lines indicate the shapes of the landforms represented on a topographic map. Closely spaced contour lines indicate that the slope is steep. Widely spaced contour lines indicate that the land is relatively level.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Landforms on Topographic Maps, continued A contour line that bends to form a V shape indicates a valley. The bend in the V points toward the higher end of the valley; this V points upstream, or in the direction from which the water flows, if there is a stream. Contour lines that form closed loops indicate a hilltop or a depression. Closed loops that have short straight lines perpendicular to the inside of the loop indicate a depression.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued The diagram below shows how topographic maps represent landforms.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 3 Topographic Maps and Contour Lines Section 3 Types of Maps
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Reading Check Why do V-shaped contour lines along a river point upstream?
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Reading Check Why do V-shaped contour lines along a river point upstream? Water moves from areas of higher elevation to areas of lower elevation. Because the V shape points toward higher elevation, it points upstream.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Topographic Maps, continued Topographic Map Symbols Symbols are used to show certain features on topographic maps. Symbol color indicates the type of feature. Constructed features, such as buildings, are shown in black. Highways are shown in red. Bodies of water are colored blue, and forested areas are colored green. Contour lines are brown or black.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 3 Index Contour, Contour Interval, and Relief Section 3 Types of Maps
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Geologic Maps Geologic maps are designed to show the distribution of geologic features, such as the types of rocks found an a given area and the locations of faults, folds, and other structures. Rock Units on Geologic Maps On geologic maps, geologic units are distinguished by color. Units of similar ages are generally assigned colors in the same color family, such as different shades of blue. In addition to assigning a color, geologists assign a set of letters to each rock unit. This set of letters symbolizes the age of the rock and the name of the unit or the type of rock.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Geologic Maps, continued Other Structures on Geologic Maps Other markings on geologic maps are contact lines. A contact line indicates places at which two geologic units meet, called contacts. The two main types of contacts are faults and depositional contacts. Geologic maps also indicate the strike and slip of rock beds. Strike indicates the direction in which the beds run, and dip indicates the angle at which the beds tilt.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Soil Maps Scientists construct soil maps to classify, map, and describe soils, based on surveys of soils in a given area. Soil Surveys A soil survey consists of three main parts: text, maps, and tables. The text includes general information about the geology, topography, and climate of the area. The tables describe the types and volumes of soils in the area. The maps show the approximate locations and types of the different soils.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Soil Maps, continued Reading Check Why do scientists create soil maps?
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Soil Maps, continued Reading Check Why do scientists create soil maps? Scientists create soil maps to classify, map, and describe soils.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Soil Maps, continued Uses of Soil Maps Soil maps are valuable tools for agriculture and land management. Soil maps are used by farmers, agricultural engineers, and government agencies. The information in soil maps and soil surveys helps developers and agencies identify ways to conserve and use soil and plan sites for future development.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Types of Maps Chapter 3 Other Types of Maps Maps are useful to every branch of Earth science. Maps that show topography and rock and soil types are only one useful type of map. Some Earth scientists use maps to show the location and flow of both water and air. Other types of Earth scientists use maps to study changes in Earth’s surface over time.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Maps in Action Chapter 3 Maps in Action Topographic Map of the Desolation Watershed
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Models of the Earth Chapter 3 Brain Food Video Quiz
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice 1.How can you determine whether the contours on a topographic map show a gradual slope? A. Look for V-shaped contour lines. B. Look for widely spaced contour lines. C. Look for short, straight lines inside the loop. D. Look for tightly spaced, circular contour lines. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 1.How can you determine whether the contours on a topographic map show a gradual slope? A. Look for V-shaped contour lines. B. Look for widely spaced contour lines. C. Look for short, straight lines inside the loop. D. Look for tightly spaced, circular contour lines. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 2. How far apart would two successive index contours be on a map with a contour interval of 5 meters? F. 5 meters G. 10 meters H. 20 meters I. 25 meters Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 2. How far apart would two successive index contours be on a map with a contour interval of 5 meters? F. 5 meters G. 10 meters H. 20 meters I. 25 meters Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 3. What part of a road map would you use in order to measure the distance from your current location to your destination? A. latitude lines B. map scale C. longitude lines D. map legend Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 3. What part of a road map would you use in order to measure the distance from your current location to your destination? A. latitude lines B. map scale C. longitude lines D. map legend Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 4. Meteorologists use isobars on a weather map in order to? F. show changes in atmospheric air pressure. G. connect points of equal temperature. H. plot local precipitation data. I. show elevation above or below sea level. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 4. Meteorologists use isobars on a weather map in order to? F. show changes in atmospheric air pressure. G. connect points of equal temperature. H. plot local precipitation data. I. show elevation above or below sea level. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. What is the angular distance, measured in degrees, east or west of the prime meridian? A. latitude B. longitude C. isogram D. relief Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. What is the angular distance, measured in degrees, east or west of the prime meridian? A. latitude B. longitude C. isogram D. relief Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response Standardized Test Prep Chapter 3 6. At what location on Earth does each new day begin at midnight?
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response, continued 6. At what location on Earth does each new day begin at midnight? International Date Line Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response, continued 7. What is the latitude of the North Pole? Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response, continued 7. What is the latitude of the North Pole? 90°N Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills Read the passage below. Then, answer questions 9–11. Map Projections Earth is a sphere, and thus its surface is curved. When a curved surface is transferred to a flat map, distortions in size, shape, distance, and direction occur. To limit these distortions, cartographers have developed many ways of transferring a three-dimensional curved surface to a flat map. On Mercator projections, meridians and parallels appear as straight lines. These lines cross each other at 90° angles and form a grid. On gnomonic projections, there is little distortion at one contact point on the map, which is often one of the poles. But distortion in direction and distance increases as distance from the point of contact increases. On conic projections, the map is accurate along one parallel of latitude. Areas near this parallel are distorted the least. However, none of these maps is an entirely accurate representation of Earth’s surface. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 9. Which of the following appears as a straight line on a gnomonic projection, where the point of contact is the North Pole? A. great circles B. parallels C. the equator D. coastlines Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 9. Which of the following appears as a straight line on a gnomonic projection, where the point of contact is the North Pole? A. great circles B. parallels C. the equator D. coastlines Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 10. Which of the following statements about Mercator projections is true? F. Because latitude and longitude form a grid, plotting great circles can be done by using a straight-edged ruler. G. Because latitude and longitude form a grid, finding specific locations is easy on a Mercator map projection. H. Mercator maps often show the greatest distortion where the projection touched the globe. I. Mercator maps often show polar regions as being much smaller than they actually are. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 10. Which of the following statements about Mercator projections is true? F. Because latitude and longitude form a grid, plotting great circles can be done by using a straight-edged ruler. G. Because latitude and longitude form a grid, finding specific locations is easy on a Mercator map projection. H. Mercator maps often show the greatest distortion where the projection touched the globe. I. Mercator maps often show polar regions as being much smaller than they actually are. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 11. Why does each map described display some sort of distortion? Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 11. Why does each map described display some sort of distortion? Any time a curved surface is mapped on a flat surface, distortion occurs. This distortion can take different forms and each map type produces different amounts of distortion. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics Use the figure below to answer questions 12–13. The figure shows the topography of the an area surrounding the Orr River. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 12. What location on the map has the steepest gradient? A. location A B. location B C. location C D. location D Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 12. What location on the map has the steepest gradient? A. location A B. location B C. location C D. location D Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 13. In which direction is the river in the topographic map flowing? What information on the map helped you determine your answer? Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 13. In which direction is the river in the topographic map flowing? What information on the map helped you determine your answer? Answers should include the following: The river is flowing from northwest to southeast; the contour lines near the river form V shapes, and the tips of the Vs point upstream; the Vs in the map point to the northwest. Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued Standardized Test Prep Chapter 3 Use the figure below to answer questions 14–15. The figure shows Earth’s system of latitude and longitude lines. Lines are shown in 30° increments.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 14. Which point is located at 30°N, 60°E? F. point E G. point F H. point G I. point H Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 14. Which point is located at 30°N, 60°E? F. point E G. point F H. point G I. point H Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 15. The distance between two lines of latitude that are 1° apart is about 111 km. What is the approximate distance between points G and E? Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics, continued 15. The distance between two lines of latitude that are 1° apart is about 111 km. What is the approximate distance between points G and E? 111 km/1° 60° = 6660 km Standardized Test Prep Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Parallels Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Meridians Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Great Circles Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Magnetic Declination of the United States Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Map Projections Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Map Projections Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Map Projections Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Topographic Maps Chapter 3
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Topographic Map of the Desolation Watershed Chapter 3