optical illiusion
Mazatlal is an especially good rock for messing with my head. I've walked away from the image on the screen then returned to see it inverted: instead of concave surfaces there are these very sedimentary looking bulges! I've seen some posts on other boards questioning if these are pillow basalts! I have to concentrate on the debris in the holes to get it right. Maybe I screwed up my brain looking at all those stereo photos over the years. Or screwed it up in other ways, I don't know. But I find it amusing everytime it flips!
Yes, the photos do support your timeline, good call. Thanks for the link, too.