Ranger Kathryn's Arches

June 11, 2009

Geology 101

Filed under: Uncategorized — Kathryn Colestock-Burke @ 7:22 am

Quick — what are the three broad categories of rock types???  If you said sedimentary, igneous, and metamorphic, you are absolutely right… and all three are in this park.  We spent all day today in the classroom and in the field, learning everything we could possibly absorb from a Ph.D. geologist.  Rocks are very, very beautiful when one knows how they came to be and why they are where they are.  Dr M reminded me of a rock CSI specialist.  She showed me ancient juniper trunks that were flat instead of round, presumably from growing in narrow cracks in ancient sandstone which then slowly crumbled and disappeared, leaving oddly squashed trunks.  Nature detectives are so cool!

Rock mysteries indicate a need for free thinkers to come along and invent a new hypothesis.  A crazy place called Upheaval Dome, in Canyonlands NP, presents an enigma that geologists are still arguing about.  Right in the middle of the huge “Island in the Sky” atop a mesa 6000 feet above sea level is a gigantic hole in the earth, two miles across.  Maybe it is a meteorite crater, but no conclusive evidence has yet been found to point to that.  The other attractive theory is that a gigantic blob of underground salt — deposited from the old oceans here — acted like a rising slug in a lava lamp.  Moving toward the surface, it eventually got pinched off and eroded away once on the surface.  You can only imagine the odd landform that resulted.  Just think of the out-of-the-box thinking that had to happen in order to even construct the salt blob theory!

The next two days, Thurs and Fri, will be spent far south of here in the Needles District of Canyonlands.  We will sleep under the stars (yes, with the scorpions) and have a naturalist present a night sky program out there away from any street light, mall or gas station.  Some of my young compadres plan to hike 11 miles to the confluence of the Green and Colorado Rivers and back, but I… I shall slowly work my way up to a hike like that. 

Create a free website or blog at WordPress.com.