Fieldwork is not for the faint hearted, especially when you are an exploratory geologist working under extreme conditions !
Puloma Chakrabarty, our next pathbreaker, Associate Mineralogist at Asbestos TEM Laboratories Inc. (Oakland, California), analyses air, water, bulk, soil, dust and cosmetic (legal) samples for asbestos (regulated and non-regulated) and other fibrous minerals / compounds.
Puloma talks to Shyam Krishnamurthy from The Interview Portal about her experiences in the field, and a memorable but challenging one being exploring for Lithium in Sweden, in bone chilling temperatures of -37 degree Celsius.
For students, you have grown up in a digital world. But always remember that the digital world would never exist without field work !
Puloma, what were your growing up years like?
I was born and brought up in Kolkata, West Bengal, India and went to La Martiniere for Girls, Kolkata for ISC (Class 12).
My extracurricular activities have been broad. As a school girl, I took part in sports (played badminton, shotput and discus – till high school level), debates and plays (I loved acting on stage, we went to different fests in schools and won prizes). While in college and university (ISM), I was the captain of the Badminton team, and we won awards in a lot of competitions. Discus and shotput were also things I believe I excelled in. Other than sports, I love reading, I am a voracious reader and I love listening to any kind of music other than death metal and techno (they hurt my ears). I trained as a singer for about 12 years, painted till the 7th year diploma, trained for tennis on clay court and swam for about 6 years.
As a graduate student, (during PhD) at University of Texas at Arlington, I had to stick to reading and music, and watching random TV shows to maintain sanity. When you are working as a researcher, there is no time to spend on leisurely activities and sports, though I sometimes hiked (to clear my mind)
Initially I wanted to pursue a career in Literature, but then Geology piqued my interest. I used to pick up rocks as a kid. My mum is a professor of Economics and dad used to be a banker at Bank of India (Deputy Gen Manager). Both were in Economics, yet I turned out to be a fool when it came to money ☺ .
What did you do for graduation/post graduation?
My BSc was in Geology (with Mathematics and Physics) from Presidency College, Kolkata and Masters in Science and Technology (3 years MSc-Tech) in Applied Geology from Indian School of Mines, Dhanbad.
I pursued MSc-Tech in Applied Geology from ISM Dhanbad. Then I worked for 2 years as an Exploration Geologist (Sweden and India). After that, I did my PhD in Geochemistry
What made you choose such an offbeat, unconventional and unusual career?
I have always enjoyed a challenge. Geology has forever been a man’s domain. I wanted to excel in it. I didn’t want to pursue a career in Engineering or Medicine. So applied science was my interest after literature.
My Masters program was in Geology, in ISM Dhanbad, the MSc course is known as 3 years MSc-Tech in Applied Geology. When I was younger, my dad was posted in Dhanbad (as a banker), so whenever I would visit him, he would take me around the campus or outside of it. There was something about the ISM campus that even as a 10–12-year-old, I found enticing. My late uncle was also a graduate from the school (BTech in Mining) a long time ago.
I did appear for the JAM exam (MSc entrance), but my BSc grades especially in pass courses weren’t good enough and I didn’t quite make it. But ISM was something I had actually wanted to go to. The tech part of the degree involved taking some courses from the petroleum engineering and mining department, with some geophysics. But it was quintessentially all in geology and technological applications in Geology. It wasn’t difficult at all for a BSc in Geology to move to MSc-Tech in Applied Geology. They used to have a separate entrance examination without any cut off, don’t know if that has changed now.
How did you plan the steps to get into the career you wanted? Tell us about your career path
During my masters, I did several internships.
My first internship was at Coal India Limited, Central Mine Planning and Design Institute Ltd, CMPDI, Ranchi, Jharkhand
Here, I prepared a graphical representation of bore hole data, coal seam structure, correlation charts, floor and roof contour plans for coal mines in Jharkhand, India and studied the methods of thermal power generation from Coal Bed Methane gas. This internship gave me good exposure to the power generation process.
My next internship was at Oil and Natural Gas Corporation, Kolkata, West Bengal
Here, I learnt detailed steps and operations concerning oil and natural gas exploration and exploitation. I also learnt about 2D Seismic Surveys, Seismic Interpretations and 3D Reconstructions, Oil Wells,and stacking processes using GPS and GIS. I gained experience with various methods of drilling, logging, cementing, coring, and casing as used in the oil industry.
My third internship was at University of Kassel, Kassel, Germany where I learnt about modeling the structure of buildings related to Earthquake Engineering and adaptations to climate change.
After completing my masters, I started as an Exploration Geologist at HDR-Salva, Sweden and India. My work involved geological mapping, geochemical analysis, logging, sampling and drilling projects for Lithium bearing Spodumene (Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate, LiAl(SiO3)2 ), and is a source of lithium in pegmatites (rocks) in Jarkvissle, Sweden . I did data analysis, evaluation and estimation for ore deposits for Thermal Power, Iron and Gold deposits in Sudan, Zambia and Mauritania, using geological knowledge and expertise in Petrology to characterise sediment as well as creating maps with DataMine and Minex. I worked here for around 1 year.
My next role was as Exploration Geologist at Geovale Pvt Ltd, India
I worked on exploration of graphite as a battery mineral in Nunasvaara and Raitajarvi, Sweden: I was involved in due diligence, assessing geological viability including recovery related issues, market analysis and finally aiding in investment decision-making (~5 months).
While working as an Exploration Geologist, I wanted to know what happened after I was done with the exploration. How was this exploration decided, I was just following orders and I wanted to know why. During my BSc and MSc-Tech, I had been super wary about Mineralogy Petrology and Geochemistry. Funnily, my PhD was in Geochemistry (Mineralogy and Petrology). I think I overcame my fear of the subject and took it head on. Now it has made a difference in my life.
My then-boss in the company, Mr. Biplob Chatterjee, was super supportive. I still contact him on a regular basis. He gave me a glowing recommendation and always has been an integral part even in my present work. I even want to work with/collaborate with him now and in the future. Such mentors are hard to come by. The same goes for my then-immediate boss, Dr. Swapnendu Goon as well. I was lucky to have met them. I still reach out to them for advice.
Can you explain your PhD in Geochemistry?
My PhD was with Dr. Asish R Basu at UT Arlington. I got the College of Science fellowship for the entirety of my PhD.
A part of my research was focused on the formation of two different compositions of rocks at the same time in the same place, which was intriguing. The difference in composition and the similar timing of the eruptions in the Deccan Flood volcanisms in India is tied to the Chicxulub impact in the Gulf of Mexico 65 Ma ago (mega-annum, million years). The resulting extinction during the Cretaceous-Paleogene boundary is associated with these volcanic eruptions as well. The main reason for the difference in composition is based on the fact that after and/or during the meteorite impact in Gulf of Mexico, the already erupting Deccan plume, across the planet in India, started to erupt even more violently and started to rise and move with more speed from the depths of the Earth. This resulted in the melting of the formed continental crust above it and then as those rocks cooled down, they formed rocks of different compositions than those already forming from the plume under the crust. These rocks were studied using their ages (U-Pb dating of zircons), chemistry (major and trace) and also the amount of heat contained in them. Because of these different conditions, the extinction was disastrous.
The other part of my dissertation was on the formation of black shales. The formation of very good quality oil and gas in South Texas Eagle Ford shales, was thought to be from under the water plume (magmatic) sources. My research showed it to be from a volcanic source. The volcanism occurred continuously for about 10 million years during which nutrient rich elements (metals) were added to the forming rock, resulting in higher oil and gas yields from them on extraction. These shales however have a swelling fraction in them, which absorbs water and swells up. Due to this swell up of minerals, the method of fracking for resource extraction, was proving to be difficult. Part of my research was to quantify the amount of these swelling clays present in these rocks, using XRD, which resulted in proving about 5-25% of these rocks being swelling minerals. I was able to devise a new method to analyze the samples on XRD without using the invasive and destructive industry process. I used this method to characterize the samples and also date the formation of the rocks, using zircon dating. Other than that, to understand the source of these rocks, I also carried out different experiments to understand the chemical composition, using XRF, Raman, whole rock and trace element analysis.
To determine the thermal maturity of the rocks, RockEval method for pyrolysis (breaking down the organic matter using fire) was carried out and results compared to data generated from a different technique (Raman microscopy). It proved a nondestructive method to analyze the samples to generate their thermal maturity. Other than that, I was able to establish a Sr-isotope curve for the seawater from carbonates around the Oceanic Anoxic Event 2 (OAE2) during which 90% of the world’s black shales were formed. This was a study of the origin and geochemistry of the black shales of Eagle Ford Texas.
After my PhD, I worked first at Columbine as a Wellsite Geologist . I was, simply put, someone who looked at the drill cores and attested to what the formations were, for oil and gas. It was something I thought I would enjoy, but ultimately I decided to go ahead and do something else.
How did you get your first break?
There is never something as a first break. It’s all about doing your best at whatever you do, such that you can go to bed at night knowing that you have done your best
I interviewed for the position when I was driving back from the wellsite. I was applying to different jobs but most were denied because of visa issues. Visa is a problem; you have to be partly lucky for that to work in your favor. I was still on my OPT when I started working in the industry. But soon I realized I wanted to go back to research and not just use my technical expertise.
What were some of the challenges you faced? How did you address them?
The main challenge is to actually find your niche in the niche. So, I have worked in oil and gas, mining and am currently working in the environmental domain. I have worked in collaboration with law firms and state agencies. I always believe that if there is no challenge, then it is not for you (it works for me). My parents have been super supportive of whichever avenue I took. According to them, I should do what makes me happy irrespective of what people might say. It is really important to have someone support you and accept your choices and not be judgmental, I have been extremely lucky in this case.
Where do you work now? What problems do you solve?
I currently work as Associate Mineralogist at Asbestos TEM Laboratories, Inc in Oakland, California.
Asbestos in general is something that is used in building materials. However, too much exposure to Asbestos causes cancer over a prolonged period of time. It has been found that the talc (in talcum powder and cosmetics) in a lot of cases are associated with asbestos (based on the geology of these formations). So more often than not, some of these cosmetics and talcum powder are found to contain asbestiform minerals.
We analyze air, water, bulk, soil, dust and cosmetic (legal) samples for asbestos (regulated and non-regulated) and other fibrous minerals / compounds by using testing methodologies such as TEM, PLM & XRD. I am responsible for primary analysis, quality control analyses and quality control refereeing, along with NIST/NVLAP accreditation proficiency for testing analyses.
We supervise the samples received, prepare samples and conduct analysis. We have to follow proper procedures, document cases from a legal perspective as well as compile lab test reports including discussion of analytical methods used and test result findings, data tables and photomicrographs.
How does your work benefit society?
We analyze the environment and determine the presence and abundance of asbestos in talcs, cosmetics and other stuff which is harmful to human health.
Tell us an example of a specific memorable work you did that is very close to you !
Too many I guess, most memorable would be exploring for Lithium in Sweden, in bone chilling temperatures of -37 degree Celsius. It was so cold that the batteries for the saws (electric) would run out of charge before we even got to the site, so we’d put them under our armpits (underneath the parka) and run to the sites. It was an eye-opener to the difficulties in working in fields. I’d return back to base and then sit in a tub with my feet in a bucket of hot water to get feeling back in my toes.
Your advice to students based on your experience?
It ain’t over till the fat lady sings! Never say never.
To continue what I love to do and do it to the best of my abilities.