Tim Demko
@timdemko
Geologist interested in the energy transition, bicycling, and public service
I used these outcrops for the classes I taught at University of Minnesota Duluth. There is actually quite a long section exposed downstream of the dam. Yes there is foliation, but bed boundaries are still discernible, as well as enough sed structures to determine way-up.
Here are responses from nearby Raspberry Shake seismometers, on the left a RS 4D in Titusville, FL 34 km to the NW, and on the right a RS 3D between Vienna and Melbourne, FL 38 km to the SW of the event. The 4D picked up higher frequency vibrations (peak ~6Hz) while the 3D recorded lower (~0.85 Hz).
I've started my new job as a geologist with the Kentucky Geological Survey. There are exhibits of two types of fossil trees in and around the KGS building: a cast of a Carboniferous lycopod (my MS thesis) and petrified wood from the Triassic Chinle Formation (my PhD). The universe is a closed loop.
You could also make the Grand Tour, visiting the Salton Sea Mud Volcanos and visit the tourist haunts of the Republic of Slowjamistan. Don't forget the guacamole recipe! vimeo.com/128414770?fl...
I rarely post photos of myself, especially in uniform, but the events of today are clashing mightily with the stupendous day I had in the field yesterday. Here I am, mid geologizing mode, waxing eloquently about some fascinating details of the 1.7 byo schist in the background. Must remember...
Here is the response from the earthquake near Acapulco, Mexico on my RaspberryShake 4D seismometer near Phoenix, Arizona USA, 2252 km from the event.
Same event on my RaspberryShake 4D near Phoenix, Arizona USA, 8,774 km away.
"Ghost Ranch block" (Triassic Chinle Formation), preserving numerous Coelophysis dinosaurs and other reptiles. This block is in collections of the Museum of Northern Arizona in Flagstaff, AZ USA. 16 of these blocks were distributed from New Mexico to museums and schools in the 1980s. #fossilfriday
Spectacular scenery, weather, and colleagues! And the tracks and traces weren't bad either!
We spent 10 days beach camping in northern Baja, going out every low tide to spy G. palmeri colonies, looking for the slit-like burrows, measuring individual burrow widths, excavating the makers and measuring their shell widths. Ended up with 75 individual measurements.(3/3) doi.org/10.1111/j.15...
For me, it was just looking at the title of this book in a university bookstore, probably sometime Spring semester 1991. I picked it up, turned right to font section, and within minutes, the lightbulb popped up above my head. Never looked back!
After liking this post and reading the linked paper, I was keen to see if I'm missing these features in outcrops. Tooling around some basalt flows along Kona Coast in Hawaii today (Shoreline Park, just west of Kealakekua)...well, yep! Will be keeping my eye peeled for these in older flows in AZ!
Any self-respecting ichnologist despises fish because they can make the most frustratingly uninterpretable traces. www.livescience.com/63627-puffer...
Here is the response from the event on my RaspberryShake 4D seismometer near Phoenix, AZ USA
After poking around and finding the base of the flow, the story became much richer: the basalt had flowed over some eolian dunes which sourced the water for the hydrothermal system. The sand might have accumulated as obstacle dunes around a bedrock hill, then buried by the flow in a valley. (2/2)
Saw these outcrops of the mineralized, brecciated top of a Miocene basalt flow today, evidence of an epithermal hydrothermal system. This indicates the interactions of mineralized, boiling water, explosively flashing to steam, breaking up the rock, depositing minerals in fractures and cavities (1/2)
Joe's post reminded me of this piece of artwork given to me me by the artist, William "Rockman" Gooder from Duluth, MN. William would come to my office with collections of stones he chose from the gravel beaches of Lake Superior for his artwork, asking me to to tell him the story of each one. (1/2)
MEGAQUAKE! 8.7 off of Kamchatka. Here is the response on my RaspberryShake 4D in Phoenix, AZ USA #earthquake #RaspberryShake
Here are some highlights from deep red Surprise, Arizona. There were several hundred folks lining about 4 blocks, both sides of the highway. Well behaved, except for a few drive-by hecklers. The group was very diverse, happy, and fired up! Kudos to the No Kings organizers!
Thought of this photo right away: left it all in the field! Clockwise from left: Brian Bodenbender, me, Mark Uhen: Shell, WY, July 2004. We survived.