Two summers ago, my wife (then my very new wife) Lily and I participated in a two-week workshop for teachers on the energy resources of Wyoming. We also indulged in a visit to a mineral resource site: South Pass City, a site in the southern Wind River Uplift that was the second oldest incorporated town … Read more
The Friday before last, I was in DC for a fun geology/botany field trip, and I got the opportunity to stroll around the barn at historic Peirce Mill, a historical grain mill along Rock Creek in Rock Creek Park, Washington, DC. The barn is immediately south of Tilden Street NW. It appears to have been … Read more
A couple of weeks ago, I was killing time down in Front Royal, and I spent a pleasant hour in the Royal Oak Bookshop. I saw a used paperback copy of Tony Horwitz’s classic Confederates in the Attic there, and bought it, thinking I could give it away to a friend or visitor who didn’t … Read more
[youtube=”http://www.youtube.com/watch?v=vJNSw1XtU6c”] Here’s the link to the book on Amazon.
A weekend expedition to GigaPan the C&O Canal’s singular Paw Paw Tunnel results in an exposition on Devonian sedimentation, Alleghanian mountain-building, structural geology, and the incision of the Potomac River to produce entrenched meanders.
Callan reviews a book about the historical battle over the meaning of coral reefs. Protagonists include Charles Darwin and the son of Louis Agassiz. The book’s author, David Dobbs, answers some questions for Callan and readers.
Callan visits the Sea Point migmatite, a contact between intrusive granite and older metasedimentary rocks, along the west coast of South Africa near Cape Town. His guide? None other than AGU Blogosphere blogger Evelyn Mervine of Georneys!
Picking up from the astonishing first couple of outcrops we saw of strained Seine Group metaconglomerate from the boundary between the Wabigoon and Quetico sub-provinces of the Superior Craton, our group moved on down the road. It was lovely clear fall weather near Fort Frances, and shockingly warm. Our third stop of the morning was … Read more
My man Walcott contributed a lot of images to the USGS stockpile during his travels. Today, I’ll feature one from Bishop, California, from 1894: Got it from here. Rock hammer on the left for scale. The caption reads: Plicated layers of thin bedded chert in limestone etched by erosion, Lower Cambrian (?). Hill two miles … Read more
Callan visits the grave of John Wesley Powell, second director of the USGS and explorer of the Grand Canyon, on an afternoon in Arlington National Cemetery.
While exploring the Rock Creek Cemetery last week, I noticed a couple of other interesting graves. This one, made of limestone, shows nice “reverse” cross-bedding: Here; I dialed up the contrast a bit to highlight these cool primary structures: It’s “reverse” because the tilting direction of the cross-beds switches from left (at the bottom) to … Read more
Callan pays a visit to the grave of celebrated paleontologist and geological administrator Charles D. Walcott.
Atop the glorious pile of travertine that is Pamukkale (photos 1, 2, & 3), there is an ancient ruined city called Hierapolis. It was founded by the Romans in the second century BC, and was constructed (not surprisingly) from the most common locally available stone: travertine. A tomb with a view: This last one is … Read more
I was sent a review copy of a new book about the Earth’s magnetism, and I finished reading it last week. It’s called North Pole, South Pole: The Epic Quest to Solve the Great Mystery of Earth’s Magnetism, and the author is Gillian Turner, a senior lecturer in physics and geophysics at Victoria University in … Read more
And now, for the final half of my final day in Capadoccia, Turkey… We continued hiking along up the scenic valley that I mentioned a few days ago, checking out the lovely scene in the lovely weather… The valley floor was reasonably wet and vegetated, but the higher slopes were eroding at a rate too … Read more
I’ve got two more batches of Capadoccia photos for you. Sorry if you feel bored with this continuing series — but I think it was not only my favorite part of Turkey (and geomorphologically interesting) but photogenic too… So on our final day in Capadoccia, Lily and I took a hike up another valley. We … Read more
Callan shares some more images from last summer’s trip to Capadoccia, Turkey. Eroded turrets of ignimbrite served as dwellings for Byzantine-era Christians, who decorated them with distinctive art.
Click this image to go to a big panorama (but not big enough to be hosted by Gigapan) of one of the valleys near Göreme, Capadoccia, Turkey: Note: The agriculture that lines the bottom of the valley. The colors of the tuff, and how they vary from place to place. The differentially eroding layer that … Read more
Today, you get the first of several batches of photos dealing with one of the most magical places I’ve ever been, the Cappadocia region of Turkey. Cappadocia (pronounced “kap-uh-doke-ee-yuh“) is an area of eroded volcanic tuffs. The overall effect is badlands-like, but without the micro-turrets and hoodoos. The individual erosional remnants are larger in Cappadocia … Read more
