Computer animations to visualize geological structures

Geology 342-Laboratory
Structural Geology

Lab 3 - Visualizing Geological Contacts and Map Patterns
These exercises use computer animations of 3D blocks with simple topography cut by a planar surface. This surface could be, for example, a bed, a dike, or a fault. Specific map patterns result from the intersection of the tilted layer with the topographic surface. You need to understand how this works in order to be able to interpret geological maps effectively. This subject is discussed in Chapter 2 of the Lab Manual (Rowland and Duebendorfer).

These computer animations were made by Dr. Steve Reynolds from Arizona State University, Tempe. His website contains many excellent resources to help you learn to visualize both topographic and geologic features (http://geology.asu.edu/~sreynolds).

Do each one of the exercises below.

Objective What is it? What to do?

A. Visualizing outcrop patterns over a hill.

Run the movie This animation allows you change the dip of a bed that crops out across a hill to see how the outcrop pattern varies. You can change the tilt of the bed in 10 degree increments.

On the Hill topographic map carefully draw the outcrop belt of a bed dipping:

a. 0
b. 10 N
c. 30 N
d. 90
d. 70 S (one click past vertical)

Use a different color for each outcrop and label it clearly with its dip.

B. Visualizing outcrop patterns over a valley.

Run the movie This animation allows you change the dip of a bed that outcrops across a valley to see how the outcrop pattern varies.

On the Valley topographic map carefully draw the outcrop belt of a bed dipping:

a. 0
b. 10 N
c. 30 N
d. 90
d. 70 S (one click past vertical)

Use a different color for each outcrop and label it clearly with its dip.

C. Visualizing the outcrop of a gently-dipping bed over complex topography

Run the movie This movie shows the New River Mesa area (that you already used in the toponumbers exercise) with the outcrop pattern of a layer dipping 10 degrees. You can rotate the block to see it from different angles.

On one copy the New River Mesa topographic map, carefully draw the outcrop belt the bed. Pay attention both to the location and the width of the outcrop belt.

Label your map.

D. Visualizing the outcrop of a gently-dipping bed over complex topography

Run the movie This movie shows the New River Mesa area with the outcrop pattern of a layer dipping 15 degrees. You can rotate the block to see it from different angles.
On the second copy the New River Mesa topographic map, carefully draw the outcrop belt the bed. Pay attention both to the location and the width of the outcrop belt.

Label your map.

E. Visualizing outcrop patterns over the New River Mesa

Run the movie This animation shows both the map view and a perspective view of a dipping stratum in the New River Mesa area. You can vary the tilt of the layer. Look carefully at both views of the area as you change the dip of the bed. Use this animation to help you answer the question bellow.

F. Put into words the "Rule of V's" Write a short paragraph stating what you observe about the map-view of outcrops of dipping strata over topography. Look at Chapter 2 of the lab manual for clues.

Last update 9/22/04

Objective	What is it?	What to do?
A. Visualizing outcrop patterns over a hill. Run the movie	This animation allows you change the dip of a bed that crops out across a hill to see how the outcrop pattern varies. You can change the tilt of the bed in 10 degree increments.	On the Hill topographic map carefully draw the outcrop belt of a bed dipping: a. 0 b. 10 N c. 30 N d. 90 d. 70 S (one click past vertical) Use a different color for each outcrop and label it clearly with its dip.
B. Visualizing outcrop patterns over a valley. Run the movie	This animation allows you change the dip of a bed that outcrops across a valley to see how the outcrop pattern varies.	On the Valley topographic map carefully draw the outcrop belt of a bed dipping: a. 0 b. 10 N c. 30 N d. 90 d. 70 S (one click past vertical) Use a different color for each outcrop and label it clearly with its dip.
C. Visualizing the outcrop of a gently-dipping bed over complex topography Run the movie	This movie shows the New River Mesa area (that you already used in the toponumbers exercise) with the outcrop pattern of a layer dipping 10 degrees. You can rotate the block to see it from different angles.	On one copy the New River Mesa topographic map, carefully draw the outcrop belt the bed. Pay attention both to the location and the width of the outcrop belt. Label your map.
D. Visualizing the outcrop of a gently-dipping bed over complex topography Run the movie	This movie shows the New River Mesa area with the outcrop pattern of a layer dipping 15 degrees. You can rotate the block to see it from different angles.	On the second copy the New River Mesa topographic map, carefully draw the outcrop belt the bed. Pay attention both to the location and the width of the outcrop belt. Label your map.
E. Visualizing outcrop patterns over the New River Mesa Run the movie	This animation shows both the map view and a perspective view of a dipping stratum in the New River Mesa area. You can vary the tilt of the layer.	Look carefully at both views of the area as you change the dip of the bed. Use this animation to help you answer the question bellow.
F. Put into words the "Rule of V's"		Write a short paragraph stating what you observe about the map-view of outcrops of dipping strata over topography. Look at Chapter 2 of the lab manual for clues.