My first post on my new blog, and I guess introduction and purpose are in order.
As a geography/geology undergraduate that has completed his first two years, I feel confident (enough) in my gathered knowledge coupled with a bit of experience with the tools of the trade to start expressing myself more in written form. I hope the blog will not only tune me more towards consistent writing on earth science subject matters and experiences, but also act as a kind of archive of interesting topics I have come across in course studies, field journeys, scholarly papers, publications, and other earth science activities.
Indeed I wish I could continue endlessly taking courses, perpetually learning knew things about every sphere of the earth system, but more and more I find that intermixed with studies is practical application, be it my GIS work for professors, or volunteer work for environmental agencies, or personal exploration of unique geological sites in my neck of the woods.
|The Pumice Castle at Crater Lake ©Robert Mutch|
Pumice Castle itself is a result of its material toughness and foundation standing tall while deposits and lava flows around it eroded and fell into Crater Lake. Mazama is a composite volcano, its layers alternating between air fall deposits of ash/lapilli and lava flows of a basic to andestic/rhyolitic nature. One such layer of air fall was composed primarily of violently erupted pumice, that when deposited upon the flanks of Mazama was so hot that fragments welded together, and formed a lens roughly 50-60m thick. That pumice layer is underlain by a particularly dense andesite layer from a previous flow, thus providing a strong foundation for the lens to resist erosive forces. The eruption that eventually led to the pumice castle was itself not voluminous, but was fast and explosive in a shorter-than-average time period.
|NPS diagram at the site|
I recommend Crater Lake as a definite on any North American geo-nut's bucket list, in particular the Rim drive and little side diversions to the Pinnacles (welded fumaroles), Phantom Ship (volcanic plug), Devil's Backbone (andesitic dyke) to name a few. If you're like me, music is your extra companion on fun drives, and my choice for central & south Oregon ended up being Pure Cult. There's nothing quite like driving through the desert scrub on a clear early autumn day whilst She Sells Sanctuary fills the ears.