You are browsing the archive for building stone.
7 December 2018
A summary of resources to learn about the geology of Washington, D.C. and the surrounding region, in anticipation of AGU’s Fall Meeting being held in the nation’s capital city.
18 August 2017
When in Rome, do Friday folds as the Romans do? Here are some images from my brief, sweltering visit to the Roman Forum(s) this past summer. The whole region is a jumblepile of ancient ruins in a thousand styles. Almost nothing is labeled. It looks like this: This particular building held up a bit better, and its lovely columns sported some folded marbles: Close-up shots to show the folding internal …
19 November 2015
What geological stories can be read from the stone on the front of a building? Walking past some facing stone in Baltimore, Callan discovers a wealth of little clues.
20 January 2015
As a follow-up to my post about the geology of the Acropolis klippe in Athens, Greece, and in the spirit of my post on the building stones of the Haghia Sophia in İstabul, Turkey, let’s turn our attention today to the various rocks that ancient Greeks used to construct the buildings of the Acropolis, such as the Parthenon. When we went to Greece in September, we didn’t just look at …
1 April 2013
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 constructed from local stone: metamorphic rocks of the Rock Creek Shear Zone, a ductile fault …
15 May 2012
Seen in rip-rap on the side of Naked Creek, a week ago yesterday: This boulder is exotic to its current location. It is typical of medium- and coarser-grained diabase from the Culpeper Basin, a Triassic rift valley east of the Blue Ridge. The main minerals are plagioclase (light-colored) and pyroxene (dark colored).
7 June 2011
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.
24 May 2011
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 right (for the bulk of the section). Ergo, the current started off flowing towards the …
21 May 2011
Callan pays a visit to the grave of celebrated paleontologist and geological administrator Charles D. Walcott.
11 May 2011
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 a tomb, partially engulfed by laminations of calcite… Time and travertine wait for no man: