Our final project for The Abstract in Nature is to create a multi-panel painting (at least 2 canvases) showing the essence of a location in nature that we visited several times. Yesterday I revisited Mt Diablo and spent an afternoon sketching with ink and pastel looking at shapes and forms that were repeated large and small scale in the rocks and trees. Here are my sketches:
Rock city crevices
Cracked rock
Oak shapes
Priscilla Read - Art Journey 
I really like Rock City Crevices. I can really see the depth.