Pillow basalt exposures in the Columbia River basalts
Pillow basalts form when mafic lava erupts underwater. Here are several examples from the Miocene Columbia River flood basalts, a large igneous province in eastern Washington state.
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Three GigaPans from Heard Island
The 2016 Heard Island expedition has returned. They took a GigaPan rig with them. Explore new imagery from this remote and hostile land!
Firsthand reports from Canoa, Ecuador after the quake
Callan’s mother-in-law lives in one of the most strongly-shaken regions of Ecuador. Here, she and her boyfriend recount the experience of the earthquake Saturday night and its aftermath. Includes 8 photos from the scene.
Cooling columns of the Catoctin Formation, Indian Run Overlook, Shenandoah National Park
An inaugural visit to an outcrop in Shenandoah National Park reveals the signature of lava flows ~600 million years old.
Friday fold: Shiny pahoehoe
James Farrell is our newest Friday fold source. Today he shares a primary (not tectonic) fold – the fold is in the ropy texture of a pahoehoe flow: Those colors! What a gorgeous rock. Thanks for sharing, James! You, too, can share your folds here. Send me your images. I look forward to featuring them … Read more
Timberville
Join Callan for a virtual field trip, as he shares dozens of photos from a recent ‘field review’ of a new geological map in Virginia’s Valley & Ridge province. Highlights: graptolites, trace fossils, geopetal structures, folds and faults.
3 scenes from the Timberville VA quad field review
Explore a series of spherical photos taken on a field review of a new geologic map in western Virginia.
Friday fold: Mount Monadnock, New Hampshire
It’s Friday, so in search of an appropriate fold, Joe Kopera leads us to the top of New Hampshire’s Mt. Monadnock. Bonus: boudinage!
Slumped boulder on Marshall’s Beach, San Francisco
The week before the AGU Fall Meeting, San Francisco experienced heavy rain and strong coastal wave action. These two phenomena liberated a big boulder of serpentinite on Marshall’s Beach. As it moved downhill, it opened up a scarp with views into the colluvial soil horizons.
Serpentinite mélange on Marshall’s Beach
South of the Golden Gate Bridge in San Francisco, there are beachside exposures of serpentinite mélange: tectonically sheared-out former oceanic crust accreted to western North America as part of an accretionary wedge.
Corona Heights Fault, San Francisco
At the end of the AGU Fall meeting, Callan visits the Corona Heights “mirror” fault, renowned for its gorgeous slickensides. Explore the site in photos in GigaPans.
A little geologic history before breakfast
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.
Dialing in 5 GPa on a diamond anvil cell
On a visit to the Geophysical Laboratory of the Carnegie Institution, Callan contemplates a diamond anvil cell and with a small adjustment changes the pressure by an extraordinary amount.
The final days of sub-400 ppm carbon dioxide
This is probably the last week our planet’s atmosphere will have less than 400 parts per million of carbon dioxide. When are we going to stop letting this heat-trapping waste gas pile up in our home?
New LiDAR of the Fort Valley & surrounding area
New LiDAR imagery for the Fort Valley reveals bedrock structures and subtle aspects of fluvial geomorphology.
Friday fold: Prins Christian Sund, Greenland
This Friday, we are off looking for folds in South Greenland. Care to join?
Iron oxide sweat stains in sandstone
What do a sweaty baseball cap and fractured sandstone have in common? Episodes of absorption of dirty liquids that pile up material such as iron oxide at the soaking front.
Paleoslump features and fluvial incision in the Conemaugh Group, West Virginia
The answer to this week’s geological interpretation contest is revealed, sort of. Annotations, GigaPans, and outcrop detail photos reveal the story of equatorial fluvial incision and ancient slumping during the Carboniferous ice ages.
Ripple marks and trace fossils in the Rose Hill Formation
An outcrop of Silurian-aged Rose Hill Formation in West Virginia reveals excellent examples of ripple marks and trace fossils.
Friday fold: Hayward neighbor
The Friday fold is some crumpled sedimentary rock near the Hayward Fault in California.