Interpreting Ground Displacement II (Grades 9-12)
This activity is similar to activity 8. The diagram for activity
12 shows the amount of uplift in millimeters at various sites near the
summit of Kilauea Volcano. The students begin by contouring the data to
define a pattern of ground displacement. A contour interval of 5 mm
works best (i.e., 0, 5, 10, 15, ... 45). A complete description of how
to contour is given in Wood (1992). The pattern defined by the ground
displacement data is shown in activity 8.
here for the graph
for activity 12.
here for the handout
for activity 12.
Answer the following questions before contouring the ground displacement
- Is the center of ground displacement at Halemaumau Crater, the
east rift zone, or the upper southwest rift zone? (circle one)
greatest ground displacement values are along the upper southwest rift
- Does the ground displacement pattern indicate uplift or
The ground displacement values are positive,
uplift. A small area northeast of the caldera has negative values,
- What is the maximum amount of ground displacement?
Maximum uplift is greater than 45 mm but less than 50 mm.
Answer the following questions after contouring the ground displacement data.
- Does the pattern defined by the contour lines support your
Yes. The contours are parallel to, and overlap,
the southwest rift zone, with the greatest uplift along the axis of the
- Draw a line on the diagram where volcanic activity probably
The eruption would be along the southwest rift
- Did you have any difficulties defining the southwestern part of
Yes , because there are no data points.
- Draw four tilt vectors on the diagram. Hint: do not worry about
amount of tilt, only the orientation of the vector.
project away from the center of the uplift and be roughly perpendicular
to the contours. See Activity 8 for the actual tilt vectors.
After the students complete the activity, review the correct answers
using activity 8.