This is a poster for the movie Ghost in the Shell. Like the movie I, Robot it has absolutely nothing to do with the book I, Robot other than it has robots in it. It also has a naked lady. I have noticed that naked ladies attract people to blogs. I know it works on me.
A hiatus in geology is a significant interval of time where there is no rock record in an area. The boundary between the two beds is called an unconformity. Here a granite deposited 1,100 million years ago is directly touching a 500 million sandstone. This unconformity represents a 600 million year hiatus.