Geology and Economics

During our Job shadow at Polymet, Austin, Brianna, and I kept hearing that we should have a talk with the geologist, Rich, and that it would be a very interesting conversation. Well on Wednesday afternoon we got the chance to talk with him. We started by asking what he did for the mine planning and about what geologists do in general. It started out as a decent presentation but then evolved into a conversation that blew our minds. It was very difficult to wrap our heads around some of the ideas and calculations that go into geology and the geologic aspect of mine planning. We talked about the sample drilling, and how they use that information to guess what is going on underneath the ground. If the geologist is looking for fault lines, the drilling needs to be done at an angle into the ground so they can mark the bottom of it to tell how it was orientated in the ground. Then we talked about how they use this information to create a 3 dimensional model of where the ore is. This is a block model, but instead of displaying ore content it tells you the value in dollars. Each block is labeled with a price per ton of collectible ore. We also now know that this information is fed into a computer program that creates a plan for the order in which it is best to take out the ore. But even with all that, the most interesting part is when you start talking about the cutoff value. After they pull the ore out of the ground they have to decide whether to bring it to the processing plant or to put it in a waste rock stockpile. This is decided by looking at not only the amount of ore in the block but what market prices are doing. I found out that geologists and engineers in general need to know a lot more about economics than I thought. All three of us learned a lot from that meeting and had our heads spinning afterward.

Proofed by Brianna