Monday, December 13, 2010

Road Cuts Around Town

When the going gets tough, you don't have to go 120 miles to find road cuts.

MY TRAVEL AGENT is one of the hardest working retired guys I know.  When I announced last winter that I had accepted a 2010 summer job at Katmai National Park in Alaska, he catapulted into action, gluing himself to his computer and making all my travel arrangements online.  My aisle seat on the flight from Las Vegas to Anchorage gave me room to stretch my legs; I had a clean and comfortable nest for four nights at an acceptably shabby downtown Anchorage motel; the brand-new rental car was not a mud-encrusted rent-a-heap; and the final leg from Anchorage to King Salmon and park headquarters departed practically on time.  For my return trip he managed to book three nights at a fine motel in Seward and a six-hour tour on a glacier cruise.  MY TRAVEL AGENT was responsible for pretty darn near everything except flying the plane and handing out peanuts.

That was then, though, and this is now.  The Katmai visitor facilities closed up for the season in September, my summer job ended, and I came back home to Utah.    Snow is deepening on the Alaskan mountainsides; rivers and lakes are likely starting to freeze solid.  The brown bears surely have gone into their winter hibernation.  Many of earth’s critters are burrowing down, to survive the season on stored reserves.  But not all of them!  When the going gets tough and life slows down for the winter, MY TRAVEL AGENT stays in high gear.  Here in southwest Utah, he can frequently be found toodling around the desert in search of interesting geology to show me.  This past weekend he took me on a short drive to investigate some road cuts on the edge of town.  

Road cut in gypsum beds
These beds are mainly gypsum, an evaporite mineral found in sedimentary rocks. Gypsum may form by precipitation from saline waters (such as shallow seas) or by alteration from anhydrite (when anhydrite absorbs water, it becomes gypsum). 

Due to its relatively high water content, gypsum crystals are fairly flexible; the beds bend and appear to "flow." Plus, gypsum crystals are often found intact and so are easy to pick up.

Farther outside of town is a fairly good-sized gypsum mine which has been in operation for quite a few decades.      
MTA Larry and the latest road cut

MY TRAVEL AGENT just never stops thinking of places for me to go!

Gypsum crystals with cell phone


  1. Nice travel agent. Road cuts almost anywhere can be pretty interesting, if you can find a place to park. Gypsum makes a nice stone for carving. Love the bends in the layers.

  2. Apparently the name alabaster is given to both gypsum (a sulfate) and calcite (a carbonate). The calcite is a little bit harder.
    This road cut is really weathered - I expect I'd have to dig deep to find a sample of gypsum that doesn't fall apart if I wanted to carve it.
    The bends and folding totally make it interesting!

    btw - MTA is my brother - today seen wearing the Glacier Brewhouse t-shirt I sent him from Anchorage!