Geology
Mapping Lecture
Name____________________
Standards
 Use appropriate technologies to collect, analyze and communicate scientific data
 Convey results of investigations using diagrams, charts and other data displays
I.
Latitude and Longitude
A. Lines that form a _______________ grid to __________ places on Earth’s surface
B. Earth’s ________ of rotation provides reference points for defining directions
1. These reference points are the geographic north and south ___________
2. Halfway between the north and south poles is the ___________________ – a
line that divides the Earth into northern and southern hemispheres
II.
________________
A. Latitude lines run east and west ______________ to the _____________
1. Also known as ________________
B. The equator is the reference line of latitude, so it equals ___ latitude
C. Since Earth is a sphere, the circumference of Earth is ______
D. Latitude lines are measured from 0 at the equator to 90 at the pole, and are
specified as being ___________ or __________
E. Each degree of latitude is equal to _____ km on Earth’s surface
F. Degrees of latitude are further broken down into smaller units called minutes and
seconds
1. ___________ – there are 60 minutes in 1 degree, so each minute = 1.85 km
a. The symbol for minutes is ___
2. ___________ – there are 60 seconds in each minute
a. The symbol for seconds is ___
III.
___________________
A. Longitude lines run north and south and _________ at the ___________.
1. They are also known as ____________
B. The __________ meridian, which passes through Greenwich, ____________, was
selected to be 0
C. The meridian halfway around the world from the prime meridian is 180
D. All locations ______ of the prime meridian have longitudes between 0 and 180 E
E. All locations _____ of the prime meridian have longitudes between 0 and 180 W
F. Can also be further divided into minutes and seconds
G. For meridians, the distance of a degree depends on ________________
1. At the equator, a degree is ~111 km
2. Since all meridians meet at the poles, the distance measured by a degree of
longitude ______________ when moving from the equator to the poles
a. Ex: at a latitude of 60 N, 1 degree of longitude equals ~55 km
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IV.
Great _____________
A. A circle that divides the globe into equal ____________
B. Any circle formed by two meridians of longitude that are directly ____________
each other is a great circle
C. The ____________ is the only line of latitude that is a great circle
D. Great circles are often used for _______________
E. They are the ________________ distance between two points on a sphere
V.
Magnetic Declination
A. The earth has ____________ poles and _____________ poles, which are different
from each other
B. A _______________ points to the ________________ north pole
C. The angle between the direction of the geographic north pole and geomagnetic
north pole is called the _____________ _______________
D. It is measured in degrees east or west of the geographic north pole
E. Magnetic declination __________ according to where you are on Earth
F. A compass can be set with the declination for a specific area so that it points to
geographic north
VI.
Reading a Map
A. To read a map, you must be able to find directions, calculate distances and
understand the symbols
B. Map _______________
1. The _______________ directions (N, S, E & W) are marked by a compass
_______, or by a north ___________
2. Direction is determined in relation to ____________ and ______________
3. Parallels (latitude) and meridians (longitude) are labeled in degrees,
minutes and seconds
C. Map Symbols
1. _______________ on a map are represented by ________________
2. These symbols are explained on the map _______________
D. Map ______________
1. In order to be accurate, a map must be drawn to scale
2. Map scale indicates the ________________ between distance on the
______ and __________ distance
3. Three types:
a. Graphic scale
b. Fractional scale
c. Verbal scale
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4. ________________ Scale
a. A printed line with markings similar to those on a ruler
b. The line represents certain distance, such as a mile or kilometer,
and may be broken down into smaller segments
5. _________________ Scale
a. Expresses distance as a ___________
b. Ex: a scale of 1:25,000 indicates that 1 unit of distance on the map
represents 25,000 of the same unit on Earth
c. The larger the ratio of the map, the less detail is shown
6. ________________ Scale
a. Expresses scale in _________________ form
i.
Ex: 1 cm on the map is equal to 1 km on earth
VII. Types of Maps
A. There are many different types of maps
B. Examples of maps used in geology include, but are not limited to:
1. Geologic maps
2. Topographic maps
C. __________________ Maps
1. Show the rocks and geologic features that are exposed at the surface
VIII. __________________ Maps
A. Show the topography of a given area
1. _________________ – the elevation, change in elevation and shape of a
region
2. ______________ is the distance above, or below, _________ level
B. _______________ Lines
1. ________________ is represented by contour lines
2. They connect points of ___________ elevation
3. The shape of the contour lines reflects the ____________ of the land
4. Contour lines never ______________ (if they did, they point where they
crossed would have two elevations)
C. Contour Interval & Index Contours
1. Contour ___________ - the ______________ in ______________ between
one contour line and the next
2. _____________ contours - every fifth contour line on a map is made darker
and marked with the elevation
a. This makes the map less cluttered and easier to read
3. Exact elevations, such as a mountain peak, are marked by an ____ and
labeled with the elevation
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D. __________________ on Topographic Maps
1. The _____________ and _______________ of contour lines show the
shapes of the landforms represented on the map
2. ____________ spaced contour lines indicate a ______________ change in
elevation
3. ____________ spaced contour lines indicate terrain that is __________,
such as a mountain slope
4. ________________, such as volcanic craters, are marked by
_____________ –short, perpendicular lines inside a closed contour loop
5. V shaped contours indicate a _____________ , and they always point
upstream.
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L. Brown
Updated November 2014
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