# geology volcano activity and calculations

geology volcano activity and calculations.

• View the two maps
• The following instructions
• Calculating slope:
• The innermost loop on each map is the center of the volcano. On the Mt. Saint Helens map, pick two points along the black line B-Bâ€™ where two different brown lines cross the black line. It doesnâ€™t matter which two brown lines you choose as long as they are on the same side of the volcano (same side of innermost loop).
• Determine the values of the two brown lines you chose. Notice the values of some brown lines are on the map. Subtract the two. Include units of feet.
• Next determine the distance between the brown lines you chose. Lay the edge of a piece of scratch paper across line B-Bâ€™. Put a tick mark at the two brown lines you chose. Now pick up the piece of paper and lay it across the scale. How many miles did you get? You will need to estimate.
• Multiply your letter â€œcâ€ answer by 5280 since there are 5280 feet in 1 mile.
• Now divide letter â€œbâ€ answer by letter â€œdâ€ answer. Since you have feet divided by feet, the units cancel out (no units). Your answer will be a number (decimal) less than 1.
• Do the same process for Mauna Loa.
• Determining the distance across the volcano: make sure you measure all the way across the entire box from corner to corner (not the length of the black line).
• Determining relief: youâ€™ll either need to add or subtract. Youâ€™ve already determined the maximum elevation (value of the innermost loop on each volcano). Now either add or subtract the values given to you in the box depending on whether the base of the mountain is below or above sea level.

geology volcano activity and calculations