Three new videos from Montana
I spent several enjoyable weeks in Montana last month, and shot some new video content there for my YouTube channel. Here are three videos that may be of interest to readers of this blog:
volcano
The Last Volcano, by John Dvorak
A new week, a new nonfiction geology book by John Dvorak! This one is a biography of Thomas Jaggar, who founded the Hawaiian Volcano Observatory. It was a really interesting portrait of a man driven to spend time with erupting mountains. The book begins with the eruption of Mt. Pelee in Martinique, a harrowing pyroclastic … Read more
Pillbug tracks in ash from Mt. St. Helens
Reader Nancy Weidman (who supplied the Wind River boudinaged basaltic dike images from earlier in the week) sent me this interesting note: Your ichnoanalogue post reminds me of the insect or pillbug tracks I found in Mt. St. Helens ash deposited in Missoula, Montana. At least some of the tracks, if I recall correctly, ended … Read more
Super Volcanoes, by Robin George Andrews
Callan reviews the debut book by volcanologist Robin George Andrews. It details the diverse eruptive histories of Kilauea, Yellowstone, Ol Doinyo Lengai, the oceanic ridge system, our Moon, the planets Mars and Venus, and the cryovolcanoes of the outer solar system moons.
Ms. Adventure by Jess Phoenix
Jess Phoenix first came onto my radar when she ran for Congress in 2018. Since that time, and thanks to Twitter’s ability to connect geologists, Jess and I co-hosted a 2019 Pardee Symposium on geoscience communication at the GSA annual meeting in Phoenix, Arizona. Jess stepped in at the last minute to cover for Iain … Read more
Friday fold: blueschist & eclogite at Jenner, California
A pre-Fall Meeting field trip to the coast of northern California yields rare sights of garnet-bearing blueschist, plus eclogite, some pillow basalts, birds, waves, wind, and a lot of rain.
Friday fold: crumpled green metavolcanics from St. Anthony
The Friday fold erupted out of a volcano, completing the second part of its two stage cooling history, then later got folded and metamorphosed. It was found atop a high cliff near the northern Newfoundland town of St. Anthony.
The End, by Phil Torres
I’ve been fortunate lately to get to meet and interact with Phil Torres, independent scholar of existential risks. At my prompting, Phil came to a GSW meeting where Peter Brannen was talking about mass extinctions, and later he came to my class to talk to my Historical Geology students at NOVA about risks humanity faces. … Read more
Friday folds: Sardinian tuff
It’s the last day of the work week. Some photos of isoclinal syn-depositional folding in Sardinian tuff will get your Friday off on the right foot.
Geology of the Galapagos Islands
Dozens of delectable geological images from the Galapagos Islands, showing fluid basalt flows and violent pyroclastic deposits along with many primary volcanic features (and a bit of sedimentology thrown in for good measure).
Cross-bedding in Archean komatiitic ash deposits
Cross-bedding isn’t just for modern sedimentary deposits; you can find it in truly ancient ash deposits too! Let’s head to South Africa and take a look.
Friday folds: Hayden Butte (“A Mountain”), Tempe
In keeping with the Arizonarific theme of this week’s posts (thanks to my participation in the 2018 Structural Geology and Tectonics Forum), I thought I would wrap up my ‘geology of the Phoenix area‘ posts with a walk I took on my last day there. This was to what Google Maps calls “Hayden Butte,” but … Read more
People and Pyroclastics: Mount Agung at the Confluence of Science and Society
A guest post from an American expat living in east Bali, displaced with his family from their home due to Mount Agung’s recent eruption, and trying to help out as best he can.
Friday fold: bend in a vesicular lava flow, Etna
It’s the First Friday of Fall! Here’s a sort of fold to help you celebrate: a section through a ∧ shaped bend in a vesicular basalt flow from the eastern flanks of Mount Etna in Sicily. It’s due to volcanic lava flowing rather than ductile deformation of a pre-existing solid rock (our usual habit with … Read more
Flow-banded rhyolite from Vulcano, Italy
I collected only a single rock on my summer travels in France and Italy. (Those of you who know me will realize how extraordinary this low number is!) It’s a flow-banded rhyolite from Vulcano, in the Aeolian Islands north of Sicily a few weeks ago. It contains porphyritic vesicular basalt xenoliths. I featured a similar … Read more
Accretionary lapilli from Archean volcanic eruptions
Volcanic “hailstones” called accretionary lapilli rained down on South Africa 3 billion years ago, and have survived to be seen in the present day, along the R40 road through Barberton Mountain Land, near the Bulembu border crossing into Swaziland.
Pseudocraters at Lake Mývatn, Iceland
Near the southern end of Lake Mývatn, astride the Mid-Atlantic Rift in northern Iceland, lies a field of “pseudocraters” that result from steam explosions beneath a fresh lava flow. Put on your head-net and join us to check it out!
A virtual field trip to the Grind of the Navir
On the northwestern coast of the Northmavine Peninsula of Shetland, there is an unusual coastal landform: a gate-like entrance to an elevated amphitheater, like something out of Tolkien, and a storm beach of slab-like boulders inland of that.
An oddball at Eshaness
In eastern Shetland, the sea chews away at the innards of a Devonian stratovolcano. But there’s an odd visitor there too – and we’re not talking about the blogger.
More Messengers from the Mantle
Since I showed off the 3D kimberlite intrusion breccias yesterday, I feel as if I owe you some other photos from that lovely exhibit at the IGC. I apologize for the poor quality of these photos – the gorgeous samples were behind glass and brightly lit, which made photography difficult. But the rocks are sooooooooo … Read more