Below is a reference to just what an ophiolite sequence is... Take a look at the page - in simple terms the ophiolites are most likely the edge of the farallon plate at the end of its subduction along our continental margin as it jammed up against the north american plate before we had transform motion.

Don - have you seen this page: http://quake.wr.usgs.gov/prepare/ncep/a_greatvalley.html - its a table showing 14 possible areas of the Great valley fault and possible quake hazards as well as some reference to research publications.

• ophiolite sequence