Why does the Hayward Fault trench show 9000 year old silt on one side, and 4000 year old sand, gravel and silt on the other side? Doesn't that imply that the Hayward fault exhibited vertical motion, not just horizontal strike-slip motion?
No! Click here to see why.
![[West side of Alameda Creek]](alamedacreek-west.jpg)
![[East side of Alameda Creek]](alamedacreek-east.jpg)