Tony, Russell,..interesting, and could be worth documenting...for example, from some sort of fixed viewpoint take pictures of same thing at regular intervals and post them. I think Tony's earlier posts on this are part of what is lost from the archives? So, I forget the details...it would be important if there is oil and gas activity in the area...meaning...if producers if oil are injecting fluid/manipulating pressures to increase production. I'd also like to know exactly where this is with a latitude and longitude...so can find it on a fault map. But, seeps are pretty common....I went on field trips twice to the Silverthread (?) oil field where oil is coming right out of the San Cayetano fault..speaking of which, there was a M3 quake near that fault WNW of Fillmore a couple of days ago (but probably not on that fault). Some of the largest natural oil and gas seeps in the world are in Santa Barbara Channel by the UCSB campus...flying in there on the commuter flight from LAX on January 29 2006 the oil was very noticeable in 3 areas...more than usual...could have been light winds and low sun made it more visible, or could have been increased seepage. One of these seep fields is being studied. Natural seepage in general around southern California is less because pressures are decreased due to production. I would find it "plausible" (using "Mythbusters" terminology) that changes in seepage could occur before quakes, but that is not the same as saying that one would commonly see this. It is known that during or after quakes you see changes...but again, maybe not always...but if you had a major quake, I would expect changes in seepage in that area afterwards.
Chris