The Perfect Geologist

I had a very interesting conversation with my manager the other day. We were going to inspect one of the furthest pits and were in the light vehicle for quite some time. I took the chance to try and find out how I've been doing at my new job - I was being very subtle, of course. The conversation turned to how potential candidates are being interviewed and what skills are considered crucial. My manager had a list of three things in the following order:


1) Safety behaviours - critical in the mining environment. Does the geologist put himself or others in danger with his attitude towards safety?
2) People skills - how the job is done. Is the geologist a good fit in the current team? Will he fit in or at least be willing to work within the team?
3) Technical skills - geological knowledge and related skills.


It was interesting that the technical skills landed at the bottom of the list. But, I have heard this argument before. One can teach technical skills, but people skills are trickier. Either you're a good communicator and get the necessary information across or you can't. Geology is a service to the production and planning teams. As a geologist you have to be able to convey the right information at the right time in the right manner. Learning how to use software can be done with a few training sessions. How not to aggravate your co-workers isn't something a session with Oprah can fix :-).


In the current job market with its boom and numerous opportunities, you need to show you're a cut above the rest. Your confidence in yourself and your ability to do your job may become more crucial than your actual technical skills. So don't be scared of moving between different mining operations or commodities. A good geo is a good geo - no matter if you're Vulcan or Minex proficient. (And, yes, I only added that last sentence to be able to describe someone as Vulcan. My Star Trek roots run deep :-)

Taking Credit

Geology is easy. Being a geologist is tricky. The rocks have been the way they are now for millions of years - only our knowledge of what's beneath our feet changes. And that's where the tricky part comes in.

I've mentioned before the sometimes difficult relationship between the geologist and the engineers on a coal mine (Gaggle of Dykes). And more often than not difficult geological conditions are entirely your fault. Even though the rocks have always been like that, somehow the geologist is to blame. It is your fault if you didn't warn the production teams of the conditions ahead of time. But, the actual rocks? Definitely not.

I've had many issues underground around thick in-seam inorganics. These are sandstone lenses in the coal seam which are harder to cut and worsens the overall quality of the seam. Some stone layers can become thick quickly in a localized area and causes major problems with the crushing and transporting of the material underground. As the geologist, I can only predict what the stone will do. I cannot remove it. This is sometimes lost on the engineers.

Recently, I was underground with the foreman of the section. He took me all over, complaining about the unmanageable cutting conditions and how the huge stone layers were blocking his feeder breakers and chutes. He was ranting and then implored me: "How the hell I am suppose to cut this nonsense?" (I have censored his word choice slightly.) I very calmly replied: "With difficulty." His anger deflated immediately and he came back down to Earth. "That's probably the right answer to that kind of question," was his reply. He knew I could do nothing about the stone. His expression was quite hilarious though! I do think most of the guys get so much pressure from above that they just need to vent to an understanding person. I sometimes just fall into that role.

This kind of blaming happens quite often, so when you can take the credit for something, you should! We were busy with a large stoneworks project through a dyke and devolatilized coal (the intrusion had burnt the coal). Burnt coal is very soft and dangerous to mine through since it's so unstable. The plan was to drill boreholes to test for when we get into the normal coal again. We did a couple of samples and finally reached clean coal. When I shared the results, I was congratulated and patted on the back by everyone! It was so funny. I didn't magic the coal not being burnt - it's been like that forever. I only gave the laboratory results back. But, as I said, you get blamed so often for the state of the rocks that it was a welcome change to be congratulated.

At least mining is never boring :-).

Ash Content

Coal is different from other commodities in how varied its uses are and how non-homogenous coal seams can be. For example, gold analyses are done to determine the grade (g/t) - how many grams of gold per tonne of rock you can extract. For coal, the analyses done are so much more and goes back to the seam's original depositional environment.

Coal is classified according to rank. An increase in rank means that the coal was subjected to greater amounts of metamorphism and burial which caused an increase in the organic carbon content of the coal. In other words, the longer and the deeper the plant material was buried under sediments, the more water and gas was pressured out so that mostly carbon remained. Coal rank increases from peat, lignite, subbituminous, bituminous to anthracite. Coal in the different classes or ranks differ in their chemical and physical properties. Also, the different coal types are used in different industries such as coal gasification to create fuels, combustion for energy generation or in the metallurgical industry as coking coal.

One company's plan to promote clean coal - singing coal! :-)

The typical and basic analyses done on coal is proximate analyses. The coal is crushed in a laboratory to get a representative sample and then the various tests are done. The proximate analysis consists of ash content, volatile matter content, inherent moisture and fixed carbon content. These are all given as percentages and add up to 100%.

Ash content is what remains after all the carbon matter has combusted - the inorganic leftovers. The volatile matter are the gasses released during combustion. Inherent moisture is the water within the coal particles and the fixed carbon is the actual carbon content within the coal.

The ash and volatile matter content give a very good indication of the coal quality. For specific purposes, the ash and volatile matter will be required to fall within a specific range. Consistency in the coal is important for efficient plant operations. Ash content and volatile matter will also show you if anything has affected the coal after deposition. For example, if any igneous intrusions have gone through or nearby the coal seam, the heat from the molten rock would have burnt the coal and so removed most of it's volatile matter. This will be evident in a lower volatile matter content and higher ash content.

Coal analyses form an integral part in understanding a coal seam and ensuring it's used for the most efficient purpose. People say working in gold and platinum is difficult due to the many faults and very deep shafts - I say try building a good forecasting model for a coal deposit based on endless tables of analyses! :-)

A Beginning

As this is my first post, I wanted to explain what I do. Wikipedia has quite an information page on geology, but Google the word and you're bound to get a gazillion pages as well.
Simply put, I work with rocks. I need to understand what kind of rocks I'm working with and what dangers are involved. Right now, I'm working at an underground coal mine. The mine is about 170 m deep (whereas gold mines can be just less than 3 km deep). My job is to ensure that the mining team know exactly where the coal is found underground, what geological obstacles the team will need to mine through to get to the coal and how safe the area will be underground once the coal is removed. Longer term planning involves modeling the extent of the entire coal deposit and determining what the coal quality is and for how long the mine will be able to produce.

I got into geology because I love science and didn't want to sit in an office the whole day. I studied for 4 years and then moved from the Western Cape to Mpumalanga (South Africa) to start working at a large mining company. I've been working for 3 years now and I thoroughly enjoy it.

The picture below roughly illustrates coal geology in Mpumalanga. From the surface, you'll find different layers of various sedimentary rocks (Karoo Supergroup) with the coal seams (black) in between. The sedimentary rocks are underlain by Dwyka Group rocks and igneous rocks from the Pre-Karoo strata. Typically, you'll have a vertical shaft that has been sunk down until the desired coal seam. From there, mining takes places in the coal seam leaving behind some of the coal to support the overlying rock. The biggest danger is roof falls which can crush you and unfortunately, people have been killed.


Mining in Coal


Why am I writing this blog? I was looking for something on the internet written by fellow female
geologists who might be gay. I wanted to see how they handle the tough mining industry and what they have experienced. I couldn't find any such blogs so I decided to start my own.
I'll be sharing the strange and funny day-to-day happenings at work as well as any cool and amazing things I'm enjoying.

Geology rocks! (Final and only geology pun :-)