The classic topography question - which way does the river flow?  It’s a simple concept, really.  It’s called “The Rule of V’s” which means that when contour lines form a series of en echelon V’s, they will always point UPstream.  I know it was hard for me to grasp this and remember it when I was in intro Geology, so I figured I might as well make it easier to understand with this nifty animation!  (Not to mention I’ll be teaching the topography and GIS lab for physical geology coming up soon!)

Made from scratch using SketchUp from Trimble (Formerly Google SketchUp) and Adobe Photoshop CS5.

EDIT: Updated to show cross-sectional profile.

circuitdesign asked:

Have you seen anything that describes the "beachballs" used by geologists that describe the dynamics of specific earthquakes in a way most people can understand?

Good question! The beachballs are a hard thing to depict in just a single picture. I remember watching this little clip when I was in geophysics:

It’s a great introduction to what they mean and it even goes as far as showing the P-wave travel paths through the earth and relating them to what the beachball means.