Monday, June 19, 2017

BUARG Intern: Olivia Williams

Examining volcanic crystals in the SEM

My name is Olivia Williams, and I’m interning in the BU Antarctic Research lab this summer. I’m a rising sophomore in the College of Arts and Sciences. My majors are English and Earth & Environmental Sciences, with a focus in Earth & Climate.
This wasn’t always the path of study I had in mind for myself; when I first came to BU, I intended to study journalism. I thought that the BURECS program would be the perfect opportunity to hone my communication skills while learning more about the climate--an issue about which I have always been passionate. However, in the course of my first two semesters, I realized that I enjoy creative writing and literature much more than journalism. Meanwhile, BURECS connected me with my previously-undiscovered second love: scientific research.

I know I’m not the only person in the program to switch to an Earth & Environment major after getting involved in the department. Since I made that choice, I haven’t looked back once! Last spring, I had the opportunity to work in this lab in addition to the time I spent here for class, and that was really when I fell in love with the research being done here. From looking at diatoms under the scanning electron microscope to performing optical analysis on volcanic crystals, even tasks that may seem mundane are exciting within the wider context of the discoveries being made in the field of climate science.
Our sonicator, used to separate ash and sediment from fine contaminants, is named Sonic the Hedgehog (lab humor is the best humor!)
Most of my time this summer will be spent with volcanic ash. This ash, collected by Dr. Marchant on his many visits to Antarctica since 1986, is useful when it comes to dating the ice beneath it: if we can determine when the ash fell and prove that it has lain undisturbed since then, that tells us that the ice underneath has existed continuously for at least that span of time. One of my jobs is to manually pick out the volcanic crystals from among the pumice, glass, and rock fragments that make up most of the samples. These crystals are the part of the ash which can be dated. Picking crystals isn’t easy, though--they’re usually too small to see with the naked eye, and still appear tiny even under a light microscope’s highest magnification. I pick them up using a paintbrush with all but one of the bristles cut. The goal is to pick up only the crystal using the static electricity of the bristle. Unfortunately, the crystals are usually smaller than the width of the brush hair, and the static electricity sometimes causes them to leap across the sample tin instead of affixing themselves to the brush. Moreover, the crystals look very similar to the translucent glass littered throughout the sample. It’s time-consuming but rewarding work.

Picking crystals on the highest magnification
My tool of choice

Aside from picking crystals, my other responsibilities will be a little more eclectic. Shuhui (another BUARG intern) and I will spend some time in Little Antarctica--the room where floor-to-ceiling shelves hold dozens upon dozens of ash samples--organizing and labeling jars of ash. Each new ash sample, before being picked over, has to be cleaned to remove the fine-grained sediment mixed in with the material. And sometimes, instead of ash, I’ll be going through samples of Antarctic lakebed sediment. These particular samples hold diatoms, moss, leaves, and possibly (if we’re lucky!) beetles from about 14 million years ago, when the McMurdo dry valleys supported life in tundra lakes.
A different kind of light microscope, called a petrographic microscope, uses polarized light to turn ash and other samples into a dazzling stained-glass window, the colors of which can tell us the mineral composition of the sample
Personally, however, I prefer the petrology and mineralogy involved in the analysis of the ash. I’ve always been casually interested in geology, but I never considered it as an area of study or a career until recently. I’m excited to work in this lab through the summer and, hopefully, later in my undergraduate career as well.

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