EAS 2200 Earth Systems Lab Sessions (1146 Snee Hall) TA: Chen Chen Office: 4144 Snee Hall Email: cc839@cornell.edu Lab: Tu, Wed, 2PM - 4:25PM Office Hour: Thursday, 3PM – 5PM

Textbook: Lab notebook (bring it every week) Website: http://www.geo.cornell.edu/eas/education/course/descr/EAS220/ Lab Schedule: 12 indoor labs and 2 field trips Due Friday at 3PM: Mailbox on second floor or my office No Late Labs!

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

Fig. 1 Example of Topographic Map [1]

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

Fig. 2 Index Contour; Contour Interval [2]

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

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

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

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

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

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

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

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

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

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

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

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

References www.town.ithaca.ny.us/trans/facts/maps/3%20Topographic%20Map.pdf http://www.athro.com/geo/topo/image_f_stream.jpeg http://ozultimate.com/bushwalking/walk/722/125_2582.jpg http://dogonlanguages.org/photos/057_07_vertical_fracture_in_cliff_Kikara_JH.JPG http://www.iupui.edu/~geogdept/g108/cont_3.gif