Point and click within the figure. Controls appear when your mouse is over the figure.
- How many flows can you see?
- Why is the "base" not flat? I.E. what prevents the base from being horizontal?
- How can you tell whether the protruding rock under that wrapped base is basalt or crystaline rock?
- Look closely; is the columnar basalt "vuggy" - meaning, has it got air pockets - or is it solid? Where to you see evidence to answer this question?
The little ruler button ("Begin measure") allows calibrated measuring with mouse clicks. Click ruler button a second time to turn it off. Also, short help is given by clicking the "?" button.