Thanks everyone for the comments. You have offered a variety of different perspectives.
Christoph - A strong focal point is always nice. I was thinking shapes and textures when I shot this and thought that the window in the ridge with the converging lines behind it (as Paulo pointed out) provided a focal point but it is pretty subtle.
jmlamont - I agree, there are several possible crops - I wanted to use the window in the ridge as suggested above. IMO the shadows in your crops are pushed back a bit too much. Thanks much for your response and interest.
Eric - I made a couple attempts on this one but came back to this one as the one that came closest to what I wanted.
Francois and Paulo - mostly clay minerals in this one. For Paulo - Cretaceous mudstones from the NA western interior seaway exposed in a breached anticline.
Chuck