Differential Erosion Is Destiny

 What is your favorite landform in the Utah area?  The "monuments" (aka, buttes) of Monument Valley made a big impression on movie audiences in 1939 when John Ford's "Stagecoach" came along.  They have been icons ever since.  Or maybe you prefer steep canyon walls, mesa edges, hoodoos, arches, or just plain ol' mountains.  Some people go crazy over rock that is reddish.

All well and all good.  But what happens when you aren't a newbie tourist anymore?  How do you maintain a long-term love affair with the landforms of Utah plateau and canyon country?  This is the time for my annual advertisement for a little book I bought years ago in the visitor center in the Escalante region.  (Kanab, UT)?

Not sure where to get this book by William Lee Stokes.

The trick is to stop thinking of these landforms as a static tourist postcard, and try to imagine how they formed.  For the most part, land was uplifted a long time ago because of collision between tectonic plates, and then differential erosion of the rock produced the strange shapes that we now see.

Sometimes you see landforms that look like islands separated from their geological "mainland."  You can imagine the more erosion-resistant rock surviving while the softer stuff around it was washed away eons ago.

My recent bedroom

But let's go further and walk away entirely from the idea of prettiness and think purely of "process."  How do these damn little slot canyons start in mere dirt -- all at once!

You see a shallow gully upstream so you know the path of the water.  And then suddenly, in a matter of inches, erosion seems to explode downward into a little slot canyon!

The 'mud' landforms occur faster, on a more human time scale, so they can pull you into the mindset of 'formation' and 'process' better than the grander, more touristy things.

Of course the grander stuff is fun to look at.  I got a good sample of that at last night's bedroom:

There was a shallow, non-descript arroyo upstream that made for an easy walk, right from my bedroom.  And then it headed straight down for about a hundred feet.  I was afraid to go near the edge or let my little dog off-leash.

In comparing those small slot canyons in the mudstone with the big canyons in the sandstone, it brings to mind Henry David Thoreau's Greatest Hits album about a morning of walking around, looking at hoar frost, and then a chance look at quartz, "the frostwork of a longer night."

There is an enormous irony to looking at these landforms with a digital camera or smartphone.  Your gadget is made of silicon microelectronics, largely a technology made by "lithogaphy" (which means rock writing or drawing) on thin layers of photosensitive polymers, silicon dioxide or differentially "doped" silicon layers, all resting on the 'geological mainland' of a thick silicon wafer.  And silicon is 20% of the earth's crust!  

Silicon microelectronics happens first with additive processes, such as depositing silicon or its compounds, and then topping it off with a layer of photosensitive polymer.  After exposure to light, this polymer is either more resistant or less resistant to subsequent chemical processing.  So when a chiaroscuro pattern of light hits that photosensitive polymer, the pattern will end up being etched down into the lower layer.  (Think differential erosion.)  Thus the patterns become a Monument Valley of transistors and electrical connectors. 

Utah landforms first begin by additive processes, such as volcanic layers or by depositing an ancient seabed and lifting it up with by tectonic plates crashing into each other.

You could take a metaphorical look at all this slow lithography in Utah and wonder about our historical view of governments, families, and religions.  Historians like to dwell on new "additive" outbreaks, wars, and revolutions.  Think of these things as clickbait.

But maybe what we really see around us is what is left over time by differential erosion.  Many of the new things fizzle out quickly, while other things are more erosion resistant, such as human biological urges or tribal loyalties.