All those millions of years ago, that part of California was a lush delta flowing into the Pacific Ocean. Then a volcano blew, burying the area in ash. The fossil we found (and I still have it!) is of a leaf that was covered in that ash, called volcanic tuff.
You helped me dig through some of the white chalky tuff and then took a break to enjoy some freeze-dried ice cream I brought. See the picture on this page!
Here's a whole bunch of pictures from our expedition!
