You are browsing the archive for 2020 September.
18 September 2020
Working up some new images for my free, online Historical Geology textbook, I annotated a photograph I took in March of this alluvial fan in southern Death Valley. The development of desert varnish on older parts of the fan shows their age visually in a quick and easy way of determining fan deposit sequence: I’ve been making a lot of these animated annotations as a way of conserving space in …
11 September 2020
A hilly region of Cornwall, U.K. features beautiful folding, and a fuzzy field assistant!
4 September 2020
Busy weeks lately; apologies for the minimal bloggery, friends. For this week’s Friday fold, I offer you a view of some of the outdoor decorations at our new house: In the lower basket there is a cut and polished block of Castile Formation rock gypsum + limestone, showing varves that have been folded, apparently by hydration/dehydration volume changes of the gypsum/anyhdrite laminae: This is from the State Line outcrop on …