I left Bozeman on Saturday morning, and drove for about seven hours. I headed south through Ennis, Montana, along the western side of the Madison Range, passing by the Madison Earthquake Site landslide (from the 1959 Hebgen Lake earthquake), and then south into Idaho. I went through Island Park, Idaho, site of the caldera of one of the three big recent eruptions of the Yellowstone volcanic center. Then into northern Utah, where I got a glimpse of the Great Salt Lake. I headed up into the Wasatch Range to spend the night, just east (and several thousand feet above) Ogden, Utah. I did some birding on the reservoir there, observing the mating rituals of both the woodcock (amazing humming noise produced during flying dives) and the western grebe (neck bobbing following by synchrnonous running across the water).

The next morning, I headed west from there, into the basin, across a range, into another basin, across another range -- you get the idea. I initially intended to go hunt for trilobite fossils in the Wheeler Shale in the House Range, but the 20-mile dirt road rattled me (quite literally) and I turned around after only four miles. I got spooked: what would happen to me if the Prius broke down out here? It's really quite desolate country. I've only ever had that feeling once before, when my Dad and I drove across the Namib Desert. It's a mix of agoraphobia and anxiety over feeling inept at repairing mechanical things, like Prii and other automobiles. I chickened out -- no trilobites for me. But there was a consolation in Great Basin National Park, which was where I headed that afternoon. I did a short hike there in the Snake Range, and toured Lehman Caverns there (my third guided cave tour in two weeks!). I had my best campsite of the trip at Great Basin: montane forest, with a gurgling stream running fifteen feet from my tent. Lovely.

When I woke up, I packed up the car and coasted downhill for eight miles into the town of Baker, Nevada, where I had a great breakfast and coffee at a little cafe there. Then up and over the Snake Range, and down the next valley to the west, south for 93 miles of some of the most empty country I've ever seen in America. In an hour and a half of driving, I saw only 20 vehicles. I crossed back into Utah, and then made my way south to the edge of the Colorado Plateau, and drove up into Zion National Park. Zion is a great canyon cut into a series of sedimentary rocks. The last time I was here, 13 years ago, I walked up the Narrows, and my first order of business was to repeat that hike. There's a new shuttle system in the park now, so after parking at my campsite, I hopped on a shuttle into the park and rode it to the end. I waded into the Virgin River and shuffled upstream. In the Narrows, the Virgin River has cut down through the Navajo Sandstone, but not quite down into the weaker underlying Kayenta Formation, and so the canyon is deep but narrow. (Downstream, when it gets deep enough to tap into the Kayenta, it undermines the sandstone cliffs, and the valley widens.) "Hiking" here is one of the more unique outdoor experiences I've had. Being immersed in the cool river, surrounded by towering rock walls -- it's magical. The further upriver you hike, the less people there are, and it's like a cathedral. I went up and around several entrenched meanders, and marvelled at the alcoves, cross-bedding, and variety of cobbles in the riverbed.

Today, I'm staying in the park and heading up to Angel's Landing, a legendary hike in its own right. Tomorrow morning, bright and early, I'm off to Las Vegas to pick up my Dad and brothers for our Grand Canyon rafting trip. Not sure if I'll be able to post again until after I get out.... late next week.

Labels: birdies, fossils, grand canyon, idaho, montana, national parks, stratigraphy, travel, utah

It's been a busy week for me. I've really enjoyed my first MSSE class of the summer, Dave Lageson's "Northern Rocky Mountain Geology." Dave led us on a series of field trips within driving distance of Bozeman: the Bridger Range, the Paradise Valley, the Spanish Peaks, the Hebgen Lake earthquake scarp and Quake Lake, and today out to Ringing Rocks, the Lahood Conglomerate, and a descent into Lewis and Clark Caverns. It's been a lot of cool geology, as well as a lot of driving! In the evenings, I've been keeping busy with Shakespeare in the Parks, seeing the B Side Players, and socializing with fellow MSSE teachers. All good stuff, but it leaves little time for blogging. Tomorrow morning, I'm off to the south. I'll be on the road for another five days or so, going to Las Vegas to pick up my father and brothers and then we're going rafting down the Grand Canyon starting next Wednesday. Along the way, I hope to visit some sites in Utah, and I hope to post some updates en route. After the Canyon float, I'll head back north, again through Utah and probably western Colorado (Black Canyon of the Gunnison), before returning to Bozeman for another three MSSE classes ("Dinosaur Paleontology of the Hell Creek Formation," "Life in Extreme Environments," and "Wildlife Ecology of the Greater Yellowstone Ecosystem"). Then back east, hopefully with some Niobrara Chalk and Pierre Shale site visits along the way.

Also, along similar "rock and road" lines, I had an article published in Geotimes this month on the roadtrip I did two years ago from DC up to Alaska and back. You can check it out here.

FYI, I got a new camera for this trip, and haven't been able to download any pictures off it yet (a stupid software issue), so that's the reason for the lack of photos lately. My apologies!

Labels: grand canyon, montana, msse, utah

Sooo.... I've been "delinquent" about posting (if five days off counts as delinquent). But the long and the short of it is that I made it to Bozeman, and started classes, and have settled into life up here. After leaving Denver, I spent a couple days in Fort Collins, Colorado, staying with my undergaduate mentor professor Larry Wiseman. When I was at William and Mary, I forged a strong relationship with Larry, and that persisted even though I defected from biology (he's a developmental biologist, and chair emeritus of the department there) to geology (basically because they had more field trips). Anyhow, he and I would gather once a month or so for coffee and talk about life, the West, Ed Abbey, art, and science.

Now he's retired and pursuing bird rock art and also teaching cell biology at Colorado State University (in Fort Collins). We drove up to Rocky Mountain National Park and toured the various microbreweries and restaurants of Fort Collins (and Lyons). It was, in short, a good time.

Departing there on Saturday morning, I drove north through Wyoming, and camped at the end of the day at Buffalo Bill State Park, on the east flank of Yellowstone. On Sunday morning, I drove through the park, marvelling at six-foot-deep snow on Washburn Pass, and cruising along past tourists and bison galore. I stopped once, to look at the single petrified tree there, and then rocked and rolled on up the Paradise Valley to Livingston, and thence westward on the interstate to Bozeman.

In Bozeman, I'm enrolled in the Master of Science in Science Education program at Montana State University. It's essentially all science educators who are taking graduate coursework to become better science educators. And it's fun! This week, I'm taking Dave Lageson's class on the geology of the northern Rocky Mountains. More on that later, perhaps, but the point for now is that I'm enjoying it, and enjoying interacting with my fellow MSSE educators.

Tonight, I had a bonus, when we had a mini-conference of geobloggers. I guess there's somewhere around 50 geobloggers out there now, but we had four of them sitting at one table in Montana Ale Works, talking rocks and fossils and blogging and whatnot. That's got to be a record for the geoblogosphere. It was a lot of fun. Thanks to Mel, Brian, and Jeannette for making it happen!

Labels: field trips, montana, msse, travel, wyoming, yellowstone

Roadtrip update:

Yesterday was a good one. I started off the day at the Sternberg Museum of Natural History in Hays, Kansas. I was the first one in the door, and had the place essentially to myself. Massive mosasaur skeletons, supercool Uintacrinus slabs, plesiosaurs, and all kinds of other neat stuff. They had some less spectacular mineral displays, but the locally-derived fossils were world class. I was very impressed.

Then, driving. I made good time when the wind wasn't trying to stop me, and listening to Bill Bryson's A Short History of Nearly Everything on my iPod, I crossed into Colorado. Eastern Colorado looks a lot like Kansas, of course, but before too long had passed, I got my first view of the Rockies in the distance, "rising from the plains." I got to the Denver area around 2pm, which meant I had plenty of time before the 7pm "Geography Goes Digital" event at the Denver Museum of Nature and Science (DMNS). So I headed southwest, towards Morrison, Colorado, and "Dinosaur Ridge." Dinosaur Ridge is a hairpin driving loop on/over the Dakota Hogback, showing Mesozoic sedimentary rocks shed off the Laramide Orogeny and into the Western Interior Seaway. There's an excellent display of dinosaur tracks, and lots of cool ripple marks, trace fossils, concretions, and stratigraphy. Looking out over the crisp dry air of the Denver Basin, I really felt like "Aha! I'm finally in the West!" It was a good feeling. After hiking and exploring there, I toodled into Morrison, Colorado, and went the Morrison Museum of Natural History. There, I had the terrific good luck to run into Matt Mossbrucker, who I mentioned reading about in Smithsonian magazine back in April. The museum's volunteers were on vacation, so I had the good fortune to have a personal tour from the director! Matt showed me a wealth of incredible fossils, including the type specimen of Stegosaurus, and footprints of baby Stegosaurus and Apatosaurus -- the latter tracks were the subject of the Smithsonian article. In case you (still) haven't read the article, it looks like these baby sauropods were capable of running on their hind legs like a basilisk lizard. Matt walked me through the logic, pointing at specific pieces of evidence on the massive slab of rock. Then we were out of time, because I had to get over to the DMNS for the "Geography Goes Digital" event.

At the DMNS, I was met by Kirk Johnson, the author of a book I mentioned here a month or so ago: Cruisin' the Fossil Freeway. My friend Michelle knows Kirk, and put us in touch. (Thanks, Michelle!) Kirk has been at the DMNS for more that fifteen years, starting as a curator of paleontology, and now as a vice-president. It was very cool of him to make time to see me. Immediately, Kirk introduced me to Bob Raynolds, the speaker for the "Geography Goes Digital" event. Bob and I talked a bit about geology and teaching, and then we scooted over to the Planetarium for the main event. I took a seat, leaned back and was amazed. It was like Google Earth on steroids; a feeling like looking down from the space station on Earth. Bob led us on an exploration of areas of the world that are showing the strain of coping with climate change. He has an astonishing amount of geographical knowledge (apparently, he has traveled to more than 50 countries to do geology) and it was a real treat to tour the planet with him and 150 of the DMNS's closest friends. Afterwards, Kirk took me and another friend-of-a-friend visitor on a tour of the museum. I saw the world's second-largest gold nugget, a massive crystal of rhodochrosite, and the incredible tour through time exhibit that Kirk put together when he first got to the museum. Starting with the Ediacaran, the exhibit went through time in a series of sub-exhibits. Each started with a diorama, and then showed the fossils that the diorama was based on. There were some INCREDIBLE fossils there -- absolute stunners. Kirk confided that's just how he wanted it -- not a thousand small fossils, but a few massive ones that just knock your socks off. It was very impressive. Around 10pm, I bade Kirk farewell, and left the museum. I drove up to Boulder, Colorado, and holed up in a hotel for the night.

I feel really lucky to have visited three amazing paleontological museums in one day, and to have had personal tours from the elite of Denver paleontology. Many thanks to Matt and Kirk for making time to show me around!

Now I'm off to check out Boulder, and maybe hike in the Flatirons above town. More later.

Labels: colorado, dinosaurs, fossils, kansas, minerals, travel

Howdy folks,

I've been on the road for several days now, and thought it would be time for an update. On my first day, I got up at the crack of dawn and drove from DC out to Winchester, Virginia, where my brother lives, and had breakfast with him and his family. After saying goodbye to my passel of nieces, nephews, and the dogs Cubby and Slick, I hit the road proper. Down the Shenandoah Valley on I-81, then west on I-64 across the wide part of West Virginia. This was the Valley and Ridge province, and it's hell on the gas mileage. I dropped from 54 mpg to 53.5 by the time I got out the Allegheny Plateaus. I also saw the most expensive gas I've seen so far: $4.75 a gallon for regular unleaded. (The lowest I've seen is $3.78.)

After crossing the border into Kentucky, I deviated to the south, and around 8pm EST (7pm CST), I pulled into Mammoth Cave National Park. I got a campsite, set up the tent, and popped a bottle of homebrew. (I brought my last six bottles of Whatchagot Ale with me.) There was a racket coming from the trees: a 17-year cicada emergence was in progress, and the seething insects pulsated as they coordinated their shrill call: positively primordial. For my evening's entertainment, I attended the Park Service's "campfire" program. (Today, "campfire" means "PowerPoint slideshow," which has its advantages and its disadvantages.) It was a hot and humid night's sleep.

The next morning, I got up and made some coffee. After breaking camp, I took a hike down to the "River Styx," an emergent spring where a stream of water flows out of Mammoth Cave and into the Green River (the same Green River, by the way, of John Prine fame). I also passed one of the many entrances to the Mammoth Cave system, and felt an amazing cool breeze oozing out of the hole and flowing down a classic solution valley towards the Green River. At 10am, my tour of the cave began. Mammoth offers multiple tours of different parts of the cave at different activity levels. I signed up for the gnarliest one on offer: the so-called "Wild Cave" tour. (Tuff Cookie presciently recommended this to me, though I had in fact reserved it a couple of weeks ago.) The Wild Cave tour is different from most Mammoth tours because it's real caving, with crawling and mud and tight squeezes, and climbing skills. You've got to be reasonably fit and trim for the Wild Cave tour to work. Joining me where 11 other people with various backgrounds, including seven from the ESPN auto racing circuit. They had a fun, jocular attitude, with a lot of mutual joshing and teasing.

I was struck by a few things about Mammoth: (1) It's really big. But that's why we bother going there, and why it's a national park (it's the longest cave system in the world), so this is no big insight. (2) It's got a lot of gypsum in it. In many places, "flowers" of gypsum crystals sprout from the ceiling and walls. I asked, where's the sulfur coming from? The guides said there was a pyrite rich layer above, which was being leached by rainwater. (3) There's not a lot of stalactites in Mammoth. I've spent a lot of time in caves in West Virginia, and there are many places in them where it's nothing but stalactites. I'm not sure what's up with that, but it was noteworthy to me. (4) There are some HUGE rooms in Mammoth, with ceilings that are easily five or six stories tall. Very impressive; cathedral-like. (5) Mammoth Cave has been a tourist destination for a LONG time. People have been trekking to this destination long before there was a road network to bring them there. Back in the day (late 1700s and early 1800s), people arrived via the river rather than overland. Some of the cave was developed early on to support these visitors. Nowadays, the Park Service continues this tradition with paved walkways, lighting, and even a subterranean cafe in "sacrifice" areas of the cave. My tour passed in and out of these areas throughout our six-hour expedition.

After exiting the cool cave back into the Kentucky afternoon heat, I took a shower (the best $2 I've spent so far on the trip!) and popped into the Prius for some more driving. I headed north again, crossing briefly into Indiana, and then Illinois. I spent the night at a hotel near Mt. Vernon, Illinois. Yesterday morning, I got up and drove west all day, back on I-64 and then on I-70. I crossed the Mississippi River at St. Louis, and then crossed Missouri. Into Kansas after that: it wasn't nearly as flat as I remembered it. Part of the insight into Kansas' topography was courtesy of the Prius, which showed me (via the mpg indicator) when I was going uphill and down. A strong headwind lowered my fuel efficiency significantly, dropping it down to 52.7 mpg by day's end. There's a lot of wind out here! I was also struck by the clouds: such crazy, distinctive forms. I can see how if you were growing up here, you could get into meteorology big time. I saw a massive storm system to my south, and the local NPR affiliate was broadcasting storm warnings and tornado watches all afternoon.

I decided to stop for the night in Hays, Kansas, home of fellow geoblogger Ron Schott. As it turns out, Ron is not actually in town this week, but I may be able to hook up with him for some Kansas chalk scouting on my way back east in late July. But there's a lot to do in Hays. For dinner, I went to the Lb. Brewing Company, a craft brewery and brewpub downtown. I got a sampler of eight (small glasses) of their various beers, and enjoyed them all. Most unusual was a lemon beer which tasted a lot like lemonade. After dinner (reading Oceans of Kansas with my turkey panini), I watched another massive storm system pass to the north, with towering gray clouds and sporadic pulses of lightning. Wow.

This morning, I'm off for a run (need to stretch those legs!) and then to the Sternberg Museum of Natural History here in Hays (an affiliate of Ron's university, Fort Hays State University). The Sternberg has a reputation as having awesome fossils from the area's sedimentary strata laid down in the Western Interior Seaway. Looking forward to it.

Next stop: Denver, hopefully by 7pm so I can attend the "Geography Goes Digital" event at the Denver Museum of Nature and Science. More later...

Labels: caves, kansas, kentucky, prius, travel

Folks, I'm heading out on the road today, heading to drive from DC to Mammoth Cave, Kentucky by tonight. I'll update from the road as I can -- planning to be in Colorado by Thursday. Best wishes til then.

Labels: kentucky, travel

I leave this weekend to begin a two-month trip out west (Montana mainly, but also Grand Canyon and points in between). As I'm prepping for the trip, my cat Lola has been sabotaging my efforts to plan. Though I've reassured her that she'll get along great with my subletter, she is still obsessed with blocking my trip-planning progress.

Here she is lying on the roadmap of Colorado:



And here, covering the "explanation" for a geologic map of the states of the stable interior:



I love that my job allows me summer travel time, and I love that, living in DC, I can get a subletter to take over my rent and cat care during the time I'm away. But I will miss this little furball when I'm on the road. She's a great cat.

Labels: lola, maps, travel

Check out these amazing images of the ashy flood deposits from Chaiten volcano that have buried Chaiten town. The Volcanism Blog, by the way, is extremely consistent in quality and focus, and I tip my hat to them for doing such a great job. If you haven't already discovered that site, you should spend some time checking out their other posts too.

Labels: blogs, south america, volcano

Yesterday, I went up to Delaware Bay to help the Nature Conservancy count spawning horseshoe crabs. I carpooled with my student Efrain and his friend Dennis. We did some birding at Cape Henlopen State Park, then had dinner and a few crafty craft beers at the Dogfish Head Brewpub in Rehoboth Beach (I had crabcake, natch.), and then headed out to Big Stone Beach for the main event: the spring tide and the new moon mean spawning horseshoe crabs (Limulus polyphemus) by the thousands. We were helping the Nature Conservancy tally up the numbers of male and female crabs. You can learn more about horseshoe crabs at this excellent website. Or you can just look at these images:



























...You get the idea. Other images on the Flickr photostream. Joining a couple of medical doctors from Delaware (well, originally from Virginia, but stationed in Delaware), we surveyed the beach using TNC's rope and square-meter protocol. The weather turned cold and rainy, but we kept it up, and saw a lot of crabs. I estimate that altogether, we saw somewhere around 5,000 crabs. Pretty cool: one of the great wildlife concentrations in the world, and it's only 2.5 hours from DC. Next up: sandhill cranes on the Platte River in Nebraska, or maybe polar bears in Churchill, Manitoba...

Labels: critters, delaware, environmental, field trips, travel

My Field Studies in Geology students are required to write papers about the different outcrops we visit. Occasionally, about once per class, they write really brilliant things. Here's a quote that student Brenda used in her recent Shenandoah National Park paper:

Labels: field trips, teaching

Picking up where I left off yesterday, in describing Saturday's field trip out to western Maryland:

2:20pm: We exit Interstate 68 and go south on a dirt road for about ten or twelve miles. This road takes us through the Green Ridge State Forest, and I can tell the students are wary of it. I love a good dirt road, and this one even shows outcrops in the road surface -- resistant sedimentary layers tracing across its rutted, potholed surface. The sun comes out, and I roll down the window, relieved that the weather has finally broken.

3:00pm: We arrive at the C&O Canal's Paw Paw Tunnel, in Maryland just north of the Potomac River and the town of Paw Paw, West Virginia. ("Paw paw" is a native tree in the custard apple family with a lovely fruit also called a paw paw. They're delicious, if you can find one the raccoons haven't already claimed.) Paw Paw is the site of the most pronounced entrenched meanders seen along the length of the Potomac River. These exaggerated loops suggest an old age river system, but they are "locked" at the bottom of deep canyons, which suggests a young river system. The usual interpretation is that the Potomac is a rejuvenated river system: it was "old age," equilibrated to base level and meandering actively, but then base level dropped and it incised to a deeper level, maintaining the meandering shape even though the meanders no longer actively squiggle from side to side.

3:10pm: At the upstream end of the tunnel, we discuss the Brallier Shale (Devonian), and note the angle of the bedding here, which is tipped into the Canal's valley: ideal for landslides. When C&O Canal engineers came to the Paw Paw Bends, they faced a tough choice: construct the canal to parallel the river around its multiple entrenched meanders, or carve a tunnel through a mountain made of this stuff. They opted for the tunnel, saving 6.5 miles of Canal length, but the digging of the tunnel took 14 years!



Because the weather is good, we decide to hike over the mountain first and then walk through the tunnel on the return trip. The hike gives us views of some of the meanders' loopy shapes:



We don't see a whole lot else on the hike, but it feels good to stretch the legs.

4:oopm: We reach the Tunnel Hollow, a long linear valley on the downstream side of the tunnel. Signs of the morning's torrential rains are everywhere in the form of increased runoff. For instance, we see a large stream emerging from the base of a talus slope, flowing across the path and into the canal:



Heading up the Tunnel Hollow, we are greeted with the sight of numerous waterfalls arcing down into the valley:





Here, the layers of the Brallier Formation dip into the Tunnel Hollow, again presenting the potential for slip between the layers, and suddenly big slabs of rock dropping down into the valley. We note the "pins" holding these unstable sheets of rock in place:



4:20pm: My favorite thing about the Tunnel Hollow is the world class exposures of slickensides there. During Alleghenian mountain-building, these sheets of shale slid over one another, as a deck of cards will buckle when squeezed. Sliding between the layers ground grooves into the rock face, and also deposited mineral fibers alligned in the direction of sliding.





4:40pm: Lastly, we got to the downstream end of the Paw Paw Tunnel itself, where multiple waterfalls were cascading down onto the towpath. A fine mist fills the air, and catches the beams of sunlight. There's a nice anticline exposed just above the tunnel archway, and usually I have students climb up the stairs (on the left) to check it out up close. However, today a waterfall was landing on the stairs!







Four of us decided to go for it anyhow, just for the thrill of passing through a waterfall. Several (smarter) students who chose to stay down below pulled out their video cameras and recorded parts of our folly. Here's one showing the climb: (Unfortunately it's both silent and taken "sideways" and I'm not video-savvy enough to know how to fix it in either regard.)



Here's another video of the four of us (Nicole, Jan, Dave, and me) up on top:



4:35pm: Time to enter the tunnel. Flashlights come out, and we begin to walk through the Paw Paw Tunnel. It's a remarkable feat of engineering. It's 3/5 of a mile long, and pitch black. We walk along the towpath, where mules once pulled barges up and down the C&O Canal. It's nice and cool in there, like a cave.

5:10pm: We load up in the vans and depart the Paw Paw Tunnel. It takes a full two hours to drive back to Annandale, so we get rolling. We cross West Virginia, and then work our way east across Virginia. Several students nod off, while others discuss geology and travel along the way.

7:12pm: We return to the Annandale campus. Adios, estudiantes! The NSF crowd (Michelle and Nicole) and I retire to the Auld Shebeen in Fairfax for some Boddington's and Gaelic tunes. It's been a long day; we've covered a lot of ground and seen some cool stuff. Time for a pint!

As with yesterday's post, all photos are by Nicole LaDue, NSF. Thanks, Nicole!
Videos are courtesy of Amy Bertsch and Dean Kauffmann.

Labels: field trips, maryland, stratigraphy, structure, teaching, valley and ridge

Where's the geographical center of the United States of America? This article in today's Times visits it, or something like it, in South Dakota.

Is geoblogging a phenomenon yet? It must be, if Geotimes writes a story about it.

And: Elizabeth Kolbert profiles Buckminster Fuller in the New Yorker.

Labels: blogs, maps

Saturday morning, 6am: I roll out of bed and check the weather. Storms forecast for Hancock, Maryland, where I'm due to be leading a field trip that day. Hmmm. But based on the radar animation, it looks like they're going to hit hard from 10-11am or so, and then ease off for a bit before hitting hard again later in the day.

6:15am: Making coffee, with Lola the cat underfoot. I check the weather again, and convince myself that the timing of the rain will work for our trip's timetable. I decide to go for it.

7:00am: I call Dale Shelton (of the Maryland Geologic Survey) at home and confirm that it's okay if we go out on the outcrop if it's merely wet, but we can't go out if it's actively raining.

7:15am: I e-mail the students, confirming that the trip is a 'go.'

8:15am: "Bye, Lola!" I leave DC and drive out to Annandale. Once on campus, I gather up a few items (first aid kit, whiteboard, topographic maps), and then go out to the parking lot where students are gathering.

9:00am: We depart campus and head northwest.

9:45am: We leave the Piedmont and cross into the Blue Ridge province.

10:03am: We leave the Blue Ridge province and cross into the Valley and Ridge province (though there are a number of Marylanders who persist in calling it the "Ridge and Valley").

10:15am: The rain hits, hard. Windshield wipers on. Behind the wheel, I grimace. Hope it passes...

10:56am: We pull in to the Sideling Hill Visitor Center. Other cars containing other students are there already. We meet up and head indoors.

Sideling Hill is a massive roadcut in western Maryland. If you've ever seen it, you'd remember it. I won't go into all the geological details here, because (due to the rain) we didn't see them all. But if you're interested, you can read in more detail about Sideling Hill on my website. Long story short: We've got some early Mississippian strata here, derived from the weathering of the Acadian highlands to the east, deposited at the edge of the Kaskaskia epeiric sea. Then they were folded up during Alleghenian mountain-building.

12:00pm: After reviewing some of the salient details inside the Visitors Center where it was warm and dry, we ventured out into the rain and wind. Fortunately, a pedestrian walkway over the highway gave us a decent vantage:





Even from this limited vantage, we are able to observe and interpret some interesting features. For instance, check out the differential weathering of the shale vs. sandstone layers here on the eastern side of the outcrop. We likened this to other examples of differential weathering, like at Monument Valley, Arizona.



We also got a good view of what an oxbow lake looks like when viewed in cross-section. Note how this paleo-channel cuts into the layers beneath it, and is filled with a plug of dark shale, indicating low-energy, low-oxygen conditions.



2:00pm: After giving up on our chances to get out on the first berm of the outcrop, we depart the Sideling Hill Visitor Center, but pull over a short distance down the road to examine the diamictite on the western side of the roadcut. In drizzle, and shouting over the traffic, we discuss the multiple origins of diamictites:



2:10pm: On the road again, headed for our second destination, the Paw Paw Bends...

(More on that tomorrow)

All photos by Nicole LaDue, NSF. Thanks, Nicole!

Labels: field trips, maryland, stratigraphy, structure, valley and ridge