PALEONTOLOGICAL SOCIETY OF WASHINGTON

Maryland in the Miocene: Paleoenvironmental History of the Calvert Cliffs
Susan Kidwell, Williams Rainey Harper Professor of Geology
Department of Geophysical Sciences, University of Chicago

Wednesday, Sept. 16, 2009
7:00 p.m., in the Cooper Room, National Museum of Natural History (10th St. and Constitution Ave. in NW Washington, DC)

Meet in the Constitution Avenue lobby at 5:00 p.m. if you wish to join the PSW members for dinner at the "Elephant and Castle," NW corner of 12th & Penna. Ave., NW

Non-Smithsonian visitors will be escorted to the Cooper Room at 6:30 and 6:55 p.m.

Labels: dc, fossils, maryland, meetings, miocene, psw, smithsonian

And now, a few images from April's Environmental Geology class field trip. We made three stops: (1) a large coal-fired power plant in Maryland, (2) Westmoreland State Park in Virginia to look at coastal erosion, and (3) Prince William Forest Park in Virginia to look at pyrite emplacement and acid mine drainage.

Here's one of the bluffs on the Potomac River at Westmoreland:

Note the recent pile of breakdown in the middle of the bluff where all the water seepage is, and also the orange trail as soil from the uppermost bluff has marked another mass wasting event's passage down to the river.

These are Miocene-aged sedimentary layers known as the Calvert Formation, part of the Coastal Plain. In places, the gray clay has been altered along fracture surfaces, as shown by these orange stripes criss-crossing one another. My toes for scale:


The students spent some time searching for fossils: this is an area where lots of shark teeth are found. We didn't have much luck, but after a long cold winter, it was nice to be standing in the warm sunshine and water:


At Prince William Forest Park, we hiked down to the Cabin Branch Pyrite Mine to look at the massive denudation there due to acid mine drainage, and we also spent some time poking around for treasures, in this case chunks of pyrite:


We had better luck than at Westmoreland...




...But of course we were in a national park at Prince William, so we left the pyrite where we found it. (Westmoreland, in contrast, allows you to keep any fossils you find in loose sediment: that figures, eh?)

I'd like to say that the group of students I had in Environmental Geology this past semester was terrific, one of the best groups I've worked with in a long time. Maybe it was because the class was discussion-focused, or maybe it was the cookies we ate every Tuesday night, but it was a great experience for me, and I'm looking forward to teaching the course again. Thanks, everyone, for making it so much fun!

Labels: coastal plain, environmental, field trips, maryland, miocene, nova, ore, piedmont, virginia