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The rock mechanics lab at Lamont-Doherty was once used by a famous experimental geologist, but then was quiet for awhile. Recently Lamont hired Heather Savage to take over the lab. She and a team of postdocs, undergrads, grads, and longtime staff engineer Ted are now rehabilitating and revamping the lab for exciting new experiments. I'm part of that team and I thought I would document the task with this blog. Enjoy!

Tuesday, 28 April 2015

Hoorah for Science!

Previously I wrote about my interview with SciTechNow on PBS. Well, after months of anticipation, the episode finally aired last week.  You can check it out HERE.

Monday, 27 April 2015

Sarah's moving on up...

Previously I reported about Sarah's desktop reaction driven cracking experiments. Well, based on some really nice results that she is currently writing up, she's decided to scale up the experiment and perform it in the triaxial apparatus. First step is preparing the samples for loading. The most important thing to worry about is that they are leak tight, since she will be controlling both confining pressure and pore fluid pressure. Since she is going to be monitoring several more things than has been done in the past (including acoustic emissions and a furnace), she's got a lot of wires on there and keeping things tight was no trivial feat. After a couple of mishaps earlier in the week, on Friday she sealed up a sample, tested it for leaks on the bench top...
…and loaded it into the triax.

Ted monitored everything from the next room. After a nerve-racking hour or so of ramping up the confining pressure, it became clear that the procedure was a success! She now has the protocol for loading up the air tight samples and will commence the reaction driven cracking experiments. Go Sarah! And this all happens just in the nick of time: in June Sarah will be leaving us for UC Davis where she will start a lectureship position. Congratulations, Sarah!

Monday, 20 April 2015

When will you realize, Vienna waits for…EGU

Oh Vienna, home to so many dessert options. No sooner did I get off the plane and drop my bags in the hotel, did I find myself in the hotel bar enjoying the first of many cakes for the week.
The reason I found myself in Vienna was of course for the annual European Geological Union meeting. We Americans can't usually spend the funds to attend this meeting with any regularity. So those few times when we are invited to attend for a special session, it is a real treat. In this case, there was a session on Microstructures and Deformation Mechanisms in Ice, which received a little bit of funding from Micro-DICE in order to bring together researchers from around the world to compare notes and talk about what we are doing.  
 Our session was assigned one of the brand new PICO formats, which stands for Presenting Interactive COntent. At the designated time we all met at one of three bright orange PICO stations for the brief oral portion of the presentation. Since I came from so far, they gave me a ten-minute time slot to open up and introduce the session. Then the rest of the researchers went through "two-minute madness" in which they gave the highlights of their work and showed how their particular interactive poster worked.
After the "madness", we all stood in front of big touch screens to navigate and host our interactive poster. Although the content for an interactive poster involves many, many interlinking powerpoint pages (mine had 30 pages; the "sample" they sent us had 60!!) and was incredibly time-consuming to prepare, I kind of liked it. It was challenging to come up with this new, non-linear way of presenting data. I think it is probably going to be the wave of the future, with posters able to be navigated in our absence, so it was fun to be an early user. And since the session was on Monday, that left me time to enjoy the rest of the meeting and even sneak out a bit to see some of Vienna. Of course, that included a bit (read: heaping mounds) of the local cuisine.
And did I mention the desserts? So many desserts.

Thursday, 19 February 2015

It's moving….IT'S ALIVE!!

Huge progress in the lab today. The last month or two have been filled with a whole lot of calibrating, adjusting, wiring….
…testing, cross testing and multi component cross testing. Ted has been working his butt off getting all the electronics to talk to each other just right, getting all the limits and failsafes to do their job, and fixing last minute hydraulic leaks.
And this afternoon, we had the load cells and LVDTs hooked up and the electronics driving the hydraulics pistons. We can make it move up and down on command, in either load or position control. This is huge! THE LDEO CRY-AX IS ALIVE! We can now start squeezing and sliding the heck out of stuff! Yeah!

adventures in standard ice

One of the important parts of any laboratory study is the preparation of samples. Currently we are focusing on the fabrication of rectangular polycrystalline ice samples that we will use in the ice friction experiments. Mike will also be using them in his senior thesis project. He will expose the samples of so-called "standard ice" to various temperature pulses and characterize how they respond. Scientists over the last few decades have perfected a method for making standard ice, although in all the previous cases they made cylinders, so we are doing something a little new. I previously reported on the rectangular die that we built. Well that has gone through a few changes, including a gasketed top that screws down to prevent leakage at the top. Plus, silicone sealant has been placed at all the seams and long risers were put on the top ports…
…so that we didn't have to get our hands wet opening valves while the die and large flask were submerged in the bath.
The idea with the standard ice is that you have packed "seed ice" and liquid water both equilibrated in a big tub of ice water, getting the whole system down to exactly zero degrees C. Then you pull a vacuum on the seed ice and open the valve to the inverted flask. The cold water floods the pore space of the seed ice. You then quickly put the flooded die in the cold room (-30C) atop a copper plate and insulate the sides, promoting bottom up directional freezing of the water you introduced. The process, we found, takes a couple of hours (not counting the making of the seed ice, which I'll report on later. That's a whole other can of worms) but then you are left with this giant bucket of ice water to throw away. Seemed wasteful. So we downsized the whole shebang to this much smaller bucket, lowered the risers, and swapped out the huge inverted flask for a small squirt bottle.
The result is this fully dense rectangle of crystalline ice. Here Mike is taking a slice with a wood saw so that we can take a closer look and see how we did.
He'll be imaging the samples with the microscope we have in the cold room and then analyzing the images for things like grain growth, porosity, fracturing, etc. Take special note of what he's wearing. After one day in the cold room, he knew there had to be a better way. He came back the next day with an old plastic hazmat suit that he'd rigged up with a blowdryer to make this custom warm suit. I've got an order in for a second!


Tuesday, 27 January 2015

Outreach: Brooklyn Elementary School Science Fair

This weekend I took the Rock Mechanics show on the road! A family from Brooklyn PS372 ("The Children's School") saw our set up at Open House, got my contact information, and asked me to come to their annual Science Day.

In addition to the rock mechanics table, there were things like electrical circuits, optical illusions, ultrasound, gardening, and making silly putty. We all set up our tables in the gymnasium before the kids arrived.
I figured that some of the kids may have already had some introduction to geology, so I brought a small collection of rocks. Sure enough, when I started talking about the rock cycle, a few yelled "Igneous!" and "Sandstone!" (okay, close enough). I also brought the rock with the strain gauges and goniometer, which is always a big hit.
And of course I brought our slider block demonstration of earthquakes. Though once they figured out how the seismometer app worked it was hard to see the small motions of the block sliding over their stomping and banging on the table. I wish I would have taken a picture or two of the kids in action, but once they started arriving I was doing demos almost nonstop for three hours. It was a fun but exhausting day.



Tuesday, 6 January 2015

The rock mechanics lab supports the arts!

Meet Denise Iris, a media artist and filmmaker, and our very own "Artist in Residence" at the rock mechanics lab. Okay, not officially, but we claim her as our own now. Denise is working on a multi-screen installation piece about climate change as personified by a lone polar explorer. She shot some great action footage with an actor out in polar bear country in the Arctic and wanted to compliment it with some more controlled shots of ice freezing and melting. She got in touch with us and spent a few weeks in the lab and cold room experimenting with different effects. Below she uses a blow torch to speed up the melting process on a block of ice. You can see a sample of this melting video at her FB page.
She used the microscope in the cold room to capture video of a drop of water freezing. She played around with different freezing surfaces and compositions, but I was too cozy in my warm office to go check on her. So I have no pictures of that.  
She also took an aquarium tank that Ted found on campus and filled it with water and a chunk of our "failed" seed ice (i.e. ice that has lots of tiny bubbles which are terrible for us experimentally, but wonderful for her artistically). 
Our PR department will be doing a more detailed story about Denise's visit and our unusual collaboration in the next few weeks. At the risk of being too meta, here is a picture of Kim taking a picture of Denise taking a picture of ice.
 And here are a couple of examples of what she came up with. These are just the stills. You should see the video that she created. That bubble that looks like a drop of mercury moves around in the most mesmerizing way. I just can't wait to see her final project.
 Gorgeous! Now don't you want an artist to spend time in your rock mechanics lab? You bet you do!