1. EAS 2200 Earth Systems Lab Sessions (1146 Snee Hall)
TA: Chen Chen
Office: 4144 Snee Hall
Lab: Tu, Wed, 2PM - 4:25PM
Office Hour: Thursday, 3PM – 5PM

2. Textbook: Lab notebook (bring it every week)
Website:
Lab Schedule: 12 indoor labs and 2 field trips
Due Friday at 3PM: Mailbox on second floor
or my office
No Late Labs!

3. 2-D representation of 3-D of Earth’s surface
Topographic Map:
2-D representation of 3-D of Earth’s surface
Contour lines show elevation
eg: Fig 1 (next slide), Figure 7-B (Lab notebook)
GEOS - the pearson custom library for geography & geology

4. Fig. 1 Example of Topographic Map [1]

5. Rules for Contour lines
Index Contours
Contour Intervals
How to draw contour lines:
a. have points: line the points on the same elevation
b. have contour lines: interpolation;
extrapolation
Streams; Overhanging Cliff; Vertical Cliff; Depression Contours; Steepness
GEOS - the pearson custom library for geography & geology

6. Fig. 2 Index Contour; Contour Interval [2]

7. Streams: V pattern; Apex of V points upstream (uphill)
Fig. 3 Streams on topographic map [3]
GEOS - the pearson custom library for geography & geology

8. Contour Lines never cross each other except: where the overhanging cliff is present
Fig.4 Overhanging Cliff [4]
GEOS - the pearson custom library for geography & geology

9. Contour lines merge to form a single contour line
Fig. 5 Vertical Cliff [5]
GEOS - the pearson custom library for geography & geology

10. Depression contours: hatchure on the downhill side represent closed depressions
Steepness:
Steep slope: close contour lines; Gentle slope: far apart contour lines
Fig. 6 Depression Contours [6]
GEOS - the pearson custom library for geography & geology

11. Other Stuff for Reading Map
Relief: elevation difference between 2 points
Gradient: Relief / Distance between 2 points
Valley: High elevation on both sides
Ridge: High elevation in the middle
Top of the hill: contour lines repeat on opposite sides of a depression
Side of the hill: only repeat on one side
GEOS - the pearson custom library for geography & geology

12. When it comes to complicated maps…
Latitude and Longitude
Map Legend
Scales
PLS (Public Land Survey System)
GPS (Global Positioning System
UTM (Universal Transverse Mercator System)
GEOS - the pearson custom library for geography & geology

13. Complicated maps cont’
Ithaca’s Location: 42°26’36”N, 76°30’0”W
Latitude: 0 degree at equator; 90 N & S at poles
Longitude: east or west of Prime Meridian (which runs through Greenwich, England)
Quadrangle: section of Earth’s surface bounded by latitude and longitude
GEOS - the pearson custom library for geography & geology

15. Complicated maps cont’
Scales:
1: 24,000: Ratio Scale
1/24,000: Fractional Scale
One inch on the map equals one mile on the ground: Verbal Scale
Bar Scale:
GEOS - the pearson custom library for geography & geology

16. Complicated maps cont’
PLS: (United States) Public Land Survey System
Principal Meridians: N – S lines
Base Lines: E – W lines
Township (T1N, T2N) and Range (R1W, R2W)
Township (6 * 6 miles)  36 Section
Section  NW ¼, NE ¼, SW ¼, SE ¼. And can be further divided
Go from SMALLEST to BIGGEST when write this up
The North-South squares of the grid are called townships and are numbered relative to the base lines; the East-West squares of the grid are called ranges and are numbered relative to the principal meridian.
GEOS - the pearson custom library for geography & geology

17. W
What is located in the SW1/4, SW1/4, sec. 14, T2S, R3W?

18. Complicated maps cont’
GPS: Use Satellites to define position on the Earth relative to the World Geodetic System – based on UTM
UTM (Universal Transverse Mercator System): 60 N – S zones. (the surface of Earth between 80°S and 84°N latitude)
Specify a position: Easting coordinates, distance from W to E, in meters
Northing coordinates, distance from equator (10,000,000 meters)
GEOS - the pearson custom library for geography & geology

19. Topographic Profile and Vertical Exaggeration
Topographic Profile: cross section
Mark the section line with elevation information
Write down marks on a sheet of paper; two ends; streams
Calculate vertical exaggeration:
(I prefer this one…)
GEOS - the pearson custom library for geography & geology

21. References