Awesomely geonerdy geode street art

A graphic designer under the pseudonym “A Common Name” has made some beautiful geode street art. Cruise over to their page to check out all the pics. Below are some highlights.


Geology is on the cutting board for Scottish High Schools

Hutton Unconformity

Scotland is thought by some as the “birthplace of geology” as it is where James Hutton developed the theory of uniformitarianism. Well, it looks like the Scottish Qualifications Authority is looking to cut geology from the high school curriculum. A high school teacher is launching a campaign to stop this from happening. I heard about this through this Reddit thread:

The starter of the thread is inviting people to contribute reasons/arguments as to why cutting high school geology is bad. Feel free to post your thoughts on the reddit thread or here.

Fun with Low Reynold’s number flows

Last week the Tectonics class I’m TAing had an extra “throwaway” lecture. We decided to let the students build their own experiments to gain some intuition about Low Reynolds number flows, and what the Reynolds number means.

First we showed them a video produced by the National Committee for Fluid Mechanics Films which was an awesome NSF funded project to develop and film these complex and/or expensive experiments (which can be found on YouTube). 
One of my favorite aspects of flow is the phenomenon of low Reynolds number flows. Low Reynolds number flows are flows where inertia plays only a small roll.

The Reynolds number is a dimensionless number that can be characterized as:

Re = (Density * Length * Velocity) / Viscosity
Re = Inertia / Viscosity.

Generally if the Reynolds number is below 2000 the flow is laminar, greater than 2000 the flow is turbulent.

To tie it to geology we helped the students work through an order of magnitude calculation of mantle viscosity. Try it for yourself: Density = 3300 kg/m^3, Length = 3 X 10^6 m, Velocity = 1 cm/yr, Viscosity = 10^21 Pas. What do you get? Is the mantle a turbulent or laminar flow?

After the video we gave the students a set of ingredients and beakers to play with: canola oil, molasses, water, food coloring, and glycerin. Fun fact about glycerin, the pharmacy only sells small bottles and employees will give you VERY strange looks when you ask for a liter of the stuff.

Here are the experiments the students came up with. You’ll here conversation about flows, mantle winds, and non-school stuff in the background.

First up we have molasses poured into glycerin:

and a small amount of molasses…

My favorite: a two layer system. Bottom layer is glycerin and top layer is oil.

And a turbulent flow for good measure…

Some things to take away from the student’s experiments: our containers were too small in height for the low Reynolds number plumes to fully develop before hitting the bottom. This would also require much more glycerin, and more weird looks.

And for fun here’s a video I found of a low Reynolds number (~1000) vortex ring collision. Science is so sexy.

Yellow Bank Creek Complex #SciWrite DONE! and more news

So I finally finished my #SciWrite manuscript. I just submitted a manuscript to G-Cubed: Geochemistry, Geophysics, Geosystems. The manuscript was based on my undergraduate thesis at UC Santa Cruz on the Yellow Bank Creek Complex, the world’s largest known exposed sand injectite complex. It’s an amazing outcrop. I’ll be writing a field trip guide for the outcrop in the near future, a version of which will be posted here. I’m very excited to finally get it off my desk. Now I can get back to blogging! And onto planning summer field work, grading those labs…

Northern side of Yellow Bank Creek Complex outcrop. Yellow-tan sandstone is limonite cemented. Blue-grey sand is dolomite cemented.

Also, now that I have a submitted manuscript I updated my CV with it and finally set my McGill webpage live. I have a lot of awesome pictures posted there. Check it out. Please if you have any comments about that site (or this site too!) I’d love to hear feedback. Am I missing something crucial to my webpage that every grad student should have?, ect. Let me know!

I also want to work on a re-design for this blag, that’s on my farthest backburner, though. Any ideas?