You can see more offset channels beyond the trail.  Are these offsets longer or shorter than the offset at Wallace Creek?  Is there some way to tell whether the channels are older or younger than Wallace Creek?  We know that if a stream has been offset a greater distance (say 60 feet instead of 30), it must have been through more earthquakes.  Since these offsets are shorter than the offset at Wallace Creek, these channels must be younger than Wallace Creek.