NOVA Annandale | Geology | Bentley | Photos of geology around the world
Putting my finger on the Great Unconformity, bottom of the Grand Canyon, Arizona. The rocks below the unconformity surface are ~1.7 billion years old, and the rocks above are ~500 million years old, meaning that about 1.2 billion years of time are missing at this location along that thin surface. Summer 2008.
Monument Rocks, Kansas. These are outcrops of the Smoky Hill Chalk, a Cretaceous-aged chalk deposit laid down in the Western Interior Seaway, an epeiric sea which stretched from Texas to the Arctic Ocean. It's famous as a source of all kinds of interesting fossils, from mosasaurs to the giant turtle Archelon. Summer 2008.
Ammonites (left) and inoceramid clams (right) collected from the Bearpaw Shale, outside of Glendive, Montana. Fat Tire for scale. Summer 2008.
Dangling my feet over the edge... Angel's Landing, Zion National Park, Utah. Summer 2008.
Rejoicing at tilted strata, Dinosaur Ridge, near Morrison, Colorado. Summer 2008.
The Gros Ventre landslide, Wyoming. This is one of the classic North American landslides mentioned in most mass wasting lectures. Here, sandstone and other tilted sedimentary layers soaked up lots of water over several weeks of heavy rain, then the heavy, lubricated layers were shaken by an earthquake on June 23, 1925, prompting them to fail, sliding downhill and across the valley of the Gros Ventre River. The debris you seen in the foreground originated up on the distant mountainside, where the scars still show. The river built up behind this natural dam in a "quake lake," which then failed on May 18, 1927, devastating the town of Kelly, Wyoming, immediately downstream. This is one of the locations that my Northern Rockies Regional Field Geology course will examine in July 2009. Summer 2008.
Another classic landslide: the Madison River landslide, Montana. This mass wasting event occurred when foliated metamorphic rocks failed on August 17, 1959, again due to being shaken by an earthquake (in this case the magnitude 7.5 Hebgen Lake earthquake, which had its epicenter about 10 miles east of here). As 80 million tons of rock came crashing down, they buried a National Forest campground, and killed 28 people. As with Gros Ventre, a quake lake was formed when the Madison River suddenly became dammed; However, the U.S. Army Corps of Engineers created a spillway before the dam burst. This is one of the locations that my Northern Rockies Regional Field Geology course will examine in July 2009. Summer 2008.

Me perched atop the columnar basalts of the Giant's Causeway, County Antrim, Northern Ireland. This UNESCO World Heritage site showcases one of the premier examples of columnar jointing in the world. It's a classic. This same area was the setting for the photograph on the cover of Led Zeppelin's album "Houses of the Holy." December 2007

More photos from Northern Ireland can be seen in these posts to my geoblog.

My hands bracket a tilted zone of paleo-karst in the Mississippian-aged Madison Limestone, as exposed in the Bridger Range of Montana. With massive limestone above and below, this orangey zone speaks of a time when the limestone deposits of this area were exposed at the surface. Caves and sinkholes developed, as did an iron-rich paleo-soil. It probably looked a lot like modern-day Florida, without the strip malls and retirees. Later, the sea returned and deposited more limestone on top. The paleo-karst is obvious because it contains big blocks of limestone from cave-roof collapse, and is stained by hematite and limonite. Summer 2007.

Here's a calyx (head and tentacles) from a fossil crinoid (relative of sea urchins) which a friend found while hiking with me in the Bridger Range, Montana. These are pretty rare to find in a complete, articulated specimen.: it's a good one. Summer 2007.

Me as a Simpsons character. Summer 2007.

A geologist reacts enthusiastically to a world-class exposure of stromatolites. I'm imagining doing the backstroke in the Mesoproterozoic Belt Sea where these stromatolites grew. This is in Grinnell Glacier cirque, Glacier National Park, Montana. Up until about ten years ago, this outcrop was mantled by glacial ice, but now Grinnell Glacier has receded almost completely. While I feel sad that the glacier has died, I'm delighted at this view into the Precambrian world. Summer 2007.

Checking out Mammoth Hot Springs, Yellowstone National Park, Montana. This is a MASSIVE deposit of calcareous travertine that is still accumulating today. Underground, hot water percolates through a limestone layer, dissolveing the calcite and carrying it in solution to the surface. Once on the surface, the hot water evaporates, and the cacite is re-precipitated. The organgey-brown area at right is stained with cyanobacteria which can live in this very hot water. Summer 2007.

"That's my motto!" Watching for rocks, central Idaho. Summer 2006.

Augustine volcano, Cook Inlet, Alaska.View is from the bluff above Bishop's Beach, Homer. Summer 2006.

Columnar jointing in basalt, Columbia River Plateau, eastern Washington state. These ~17 million year old lava flows blanketed much of the Northwest in layers of basalt hundreds of feet thick. Summer 2006.

Devils Tower, Wyoming at sunrise. (Like the image above and the Giant's Causeway shot up above that), this is columnar jointing, although in a different igenous rock -- phonolite). Summer 2006.

My Westy parked amid the lava flows of Craters of the Moon National Monument, Idaho. These eruptions are interpreted as being caused by the Yellowstone hotspot at an earlier time when the North American continent was further east than it is now. As the Atlantic has widened and the Pacific has narrowed, North America has shuffled westward, causing the Yellowstone hotspot to appear to be moving eastward. There are some really nice pahoehoe-style ropy crusts on these volcanic rocks. Summer 2006.

Hole in melting glacial ice, Worthington Glacier, north of Valdez, Alaska. Holes like this increase the surface area of the glacier, meaning that there is more area over which ice is exposed to air. As a result, the ice melts faster and faster. Summer 2006.

Video of the melting at Worthington Glacier (typical of Alaska's alpine glaciers). Summer 2006.
Click on video to watch.

Northwestern Glacier, Northwestern Fjord, Kenai Fjords National Park, Alaska. In Alaska, the Ice Ages haven't ended yet. Summer 2006.

This is the one that I purchased.

Garnets for sale (quarried by local children), Wrangell, Alaska. Summer 2006.
Hover over picture to learn which one I bought.

Fossil fish from the Green River Formation, Fossil Butte National Monument, Wyoming. Summer 2006.

An assortment of Petoskey Stones (corals), plus some other cobbles of fossiliferous limestone, Petoskey State Park, Michigan. Summer 2006.

The Westy parked at an outcrop of Precambrian granite, southern Québec. Summer 2006.

Ripple marks in sandstone. Lake George, Adirondacks, New York. Summer 2006.
Semenggoh Wildlife Rehabilitation Center, outside of Kuching, Sarawak, Malaysian Borneo. These semi-wild orangutans come into the center each morning for a free handout of sugar cane and fruit. I got to feed them by hand! I know that's not geology at all, but you've got to admit, it's pretty darn cool. August 2005.

Quoddy Head, Maine, easternmost point in the U.S. I hiked here with my family along the foggy coast. August 2004.

Kissing the Blarney Stone, thereby earning the right to tell geological lies for seven years; County Cork, Ireland. December 2002.

The Blue Lagoon, a geothermal spa in Iceland. January 2003.
Me soaking in the Blue Lagoon, near Keflavik, Iceland. January 2003.

Thingvellir, the spreading zone in Iceland between the North American (left side) and Eurasian (right side) tectonic plates. January 2003.

This is the view from the edge of the Usambara Mountains in northeastern Tanzania, in East Africa, with Seth Factor (wearing glasses). July 2002.

This is a chunk of petrified log, lining a parking lot of a cheesy tourist trap near Petrified Forest National Park in Arizona. June 2002.

This is me climbing a limestone cliff in eastern Thailand's Railay Beach area. July 2001.

These are a group of islands in the Andaman Sea off the coast of eastern Thailand. Pretty scenic kayaking around these parts. July 2001.

This is the world's largest meteorite, the Hoba Meteorite, in Namibia, southwestern Africa. Can't you see it? It's in the middle. I'm pointing at it. Yes, I agree that it's remarkable that it happened to land in the middle of this little amphitheater. Sometimes nature surprises us. January 1997.

This is the tail of a humpback whale diving in Kachemak Bay, off the coast of Homer, Alaska, where I lived for a while in 1999. The mountains in the background are the Kenai range. August 1999.

This is a shamanist pile of rocks on a pass between moutains in central Mongolia. In accordance with the local tradition, I'm pictured tossing a rock onto the pile (called an ovoo) after circumambulating it three times. July 1998.
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