Department of Earth Science |Northeastern Illinois University

INTRODUCTION TO EARTH SCIENCE
ESCI 121, Fall 2006

Review for Exam #4                                                                                               Dr. Sanders

If you have trouble re-loading any of the course web pages, try this: go to the URL address box, and delete the "%7E" you see there.  Replace it with a tilde "~" (usually found at the upper left hand corner of your keyboard).  I don't know why this problem is occurring, or why the tilde seems to fix it, but give it a try!

On Exam #4, you should be able to do the following:

Topographic Maps

* Draw contours of land surface for a hill, an inclined plane, a ridge, and a valley.

* List the common elements that should appear on any map, and explain how to use and/or interpret them.
scale               north arrow               coordinate system               key/legend               title

* Explain what a contour line on a topographic map represents; tell what contour interval means and how to determine what the contour interval is on any given topographic map.

* Explore and practice the principles of contouring by participating in the following activities (see the Nov 14 agenda for larger font versions of all three activities).

 ACTIVITY ONE Crease a sheet of paper and stand it up on your desk like a tent.  Using the principles of contouring, draw the contour lines that would appear on it.  Then, draw the map that would illustrate those contours.  Flip the paper upside down so it forms a "V".  Draw the equal elevation contours and map.  Start with a fresh piece of paper, crease it, and prop one end of it on a book so it forms a tilted tent.  Draw the topographic contours and map.  Finally, flip the paper upside down so it forms a "V", tilt it, and draw the contours and map.

 ACTIVITY TWO Sketch a topographic map of the area carved in the sand on the stream table.  When you are done, have the instructor check your map. Then, construct a new shape in the sand for another group to map.  Make a map of this area too—yours will be the “answer key”.

 ACTIVITY THREE Using the topographic quadrangles of Chicago Loop and Palos Park and the key to topographic map symbols, find a place that illustrates the following features.  Label and place sticky notes on the map to indicate the location of each feature. * a gentle slope   * a steep slope   * a closed depression   * a round hill top   * a ridge (elongated hill)   * a lake * a benchmark * a stream; find two places where contour lines cross the same stream and put sticky notes on the map to show both places.  Tell what direction the stream is flowing. * a “Gaging Station” along a stream      * a forested or undeveloped area (how can you tell?) * an urban area (how can you tell?)

* Use the Public Land Survey system coordinate system (Township, Range, Section, Quarter of quarter of quarter)  to locate specific points on a topographic map.  Example: using the Palos Park quadrangle, locate the building in the following location: T37N, R12E, Sec. 14, NW ¼, SW ¼, SW ¼.

* Use the coordinate system of latitude and longitude to specify or identify a location on a topographic map.

* Explain what it means to say a map is a 7.5-minute map, and explain the difference between 7.5- and 15-minute maps.

*  Complete a topographic maps worksheet using several different maps to perform tasks such as these: identify features, use the key, measure distances, and use coordinate systems.

* Use the graphical scale on a topographic map to measure distances.  In class we used the following quads to locate and using the map scale, measure the width of the floodplain of the Mississippi River: Rockwood, Kaskaskia, Selma, Cahokia, and Blackhawk, IL.

Streams and Stream Processes

* Use topographic contours to determine what direction a stream is flowing.

* Explain what a drainage basin, or watershed is.  (Note: it is not well explained in our textbook.  Try googling --> watershed definition <-- to find some online resources.)

* Explain what a drainage area is.  (Try googling   -->  "drainage area" definition <-- to find online resources.)

* Use the USGS stream water data site to find stream flow data for streams in Illinois.

* Graph the stream data you collected from the USGS site: graph discharge vs. time, showing the 10 days before the peak flow, the day of the peak flow, and the 10 days following the peak flow.

* Compile the graphed data, and use it to describe some of the ways in which various watersheds might differ from each other (e.g. size of drainage area, degree of urbanization, and so on), and form hypotheses as to how these factors might affect streamflow during a storm.

* Use the stream table to examine the processes of erosion, transportation, and deposition of sediment.

* Sketch a map view of a meandering stream; indicate where you would expect to find erosion occurring and where you would expect to find deposition occurring.

* On a map of a stream flowing into a lake or ocean, show where a delta would form.

Ground Water

* Inject dye into a model of a ground water system, and observe what happens to it.  Pay special attention to how quickly it moves and along what path it travels.

* Identify the water table on the ground water model, and explain what the term means.

* Calculate the elevation of the water table under idle and pumping conditions for the Stermerville well worksheet.

* Draw contours of the water table on the maps for idle and pumping conditions in Stermerville.

* Determine flow directions for the Stermerville ground water.

Department of Earth Science | Northeastern Illinois University

© 2006 Laura L. Sanders.  December 7, 2006.