From Fossil To Fuel™
From Fossil To Fuel™

Episode 11 · 2 years ago

Episode 10 - Earthquakes!


Hydraulic fracturing and earthquakes. How are they linked and what are we doing about it?

My name is Brennan McDougall and I'm a professional engineer. Or the last decade I've worked in many different facets of the oil and gas industry. While I have a pretty solid technical background in oil to gas, I don't really know a whole lot about the other non technical departments that help run an oiling gas company. Recently I took a course to help develop my business acumen and better understand how the financial side of the business works. What a novel concept to educate the technical people on the business and financial side. I thought it would be a really cool idea to return the favor and educate the non technical people on the technical side. This is how the concept from fossil to fuel was born. Through these twenty four episodes, we will take a journey from how oil and gas was formed millions of years ago how it is refined into the fuel that runs our cars and heats our homes. Come join me on this adventure as we learn how the oiling gas industry operates. From fossil to feel. Earth quakes are commonly associated with natural geological processes such as volcanoes and large faults like the Mount Saint Helen's or the sound Andreas. However, fracking can also cause small earthquakes along faults. This is often referred to as induced seismicity because humans are causing the event. When we hear about oil companies causing earthquakes because of fracking, what we're really talking about is the fracs or the injection of fluids and profit, which is therefore inducing a seismic event. A seismic event is when energy is released below the surface of the earth, resulting in...

...the release of energy similar to the pressure pulse after an explosion. So, if you think about it, if you've got an explosion, whether it's a piece of dynamite or grenade or whatever, when that explosion happens you're triggering a release of energy and those waves or energy waves end up getting released across a certain area. So that would be the pressure wave or the pulse wave because of the explosion. It's similar with fracking. So you've got this high pressure fluid being injected, a large volume of it, injected, down into the rock below the surface of the earth, and it's the same kind of concept. As you're building up this energy and as the fracture of the rock is happening, that energy gets released. So natural earthquakes much like induced earthquakes. They can be caused by many things, but most often it's due to the shifting of the tectonic plates deep below the surface. So the actual mechanics and physics behind inducing an earthquake is probably a bit beyond the technical level that I'm willing to dive into for this podcast. But essentially what happens is that when we FRAC, like I said, we're pumping this high pressure fluid and this fluid will pressure EZE or increase the pressure of the pores inside the Rock. So the increased poor pressure inside the rock will put stress on the Rock, causing it to slip or move. In certain areas, this movement is known as sheer failure and that's really what triggers the earthquake. So when two pieces of rock are pushed together and rub against each other, the pressure and friction will cause them to stick together a little bit. Sheer failure occurs when there's enough force or energy for the two pieces to shear, meaning slide along one...

...another. The origin of the first break or sheer failure is called the focus of the earthquake, and the areas surface directly above this point is called the epicenter. And so remember here, when we're talking about the rocks below the surface of the earth, I'm not talking about two slabs of rock the size of a table or a car or a room. We're talking like the size of a house or an apartment building or an entire city block. And so when these things start moving, it's enormous amounts of energy that are required to do this and therefore enormous amounts of energy that get released. So I'll give you a bit of analogy to try and picture how this works in your mind. So imagine two people arm wrestling that are in a stalemate. So to the casual observer, their arms aren't moving at all, but there is a lot of force that's in a state of equilibrium and all it can take is a little help pushing on one side and all of a sudden one arm will able to overtake the other. Now imagine millions of these little arm wrestling matches going on beneath the surface of the earth between giant layers of rock that have been in this stalemate for millions of years. Eventually one side will win out and it'll shift over the other because the massive rock involved is so massive. But when this happens, the energy released when one side gives in his enormous. This release can happen naturally over time, or it can be induced by things such as dams, coal mining, drilling, even water disposal injection wells, but the most common one, or at least the one that we hear the most about, is fracking. So the action of pumping the water down a well and charging up a specific area with pressure is what can actually change the balance in those little arm wrestling matches below the surface of the earth.

Once one starts to give way, it can have a domino effect and the rock will start to break along a fault. This release of energy, as this is happening, causes seismic waves, and it's the seismic waves that make the ground shake and ultimately cause damage. If you're in an area that seismically active, meaning it has a history of earthquakes, natural earthquakes, with lots of these arm wrestling matches going on, the chances of inducing an earthquake because if racking is higher than it would be in an area with little or no history of earthquakes. Kind of intuitive, but some fract jobs can induce dozens or more of earthquakes, but most of them, or all of them, are magnitude too or less. This is on the Richter scale, which means that they aren't even felt its surface. So technically this sort of makes sense because when you're fracking you're actually, like I said, you're fracturing or shattering the rock with high pressure fluids. So it's not that much of a leap to realize that you can induce seismic events by injecting that much energy into the ground that you're going to be fracturing or shattering rock. The question really becomes one of risk tolerance and government regulation. So we know fracking can and does induce seismic events or earthquakes, not in every case, but it certainly has the potential to do so. So what's the risk of causing a significant event, and when I mean a significant event when we're fracking, if we've got, you know, ten or twenty or a hundred of these magnitude one and two seismic events or earthquakes, meaning that if you're a magnitude one or two,...'s not something that's even felt its surface. It's just it's a seismic event which means that really there's just a release of energy, which is happening anyway as we're fracking. So we're having all of these little seismic events as the rock is breaking and fracturing below the surface of the earth, and we're recording these on surface as a magnitude one or a magnitude to earthquake, and I'm using air quotation marks here. But there's no nothing felt at surface, because there's it's just energy that's being released below the surface of the earth. So those I would call non significant seismic events. But what's the risk of causing a significant seismic event? If one occurs, what could the magnitude be? Are we talk in magnitude three, four, five six? Are you in an isolated location? Because if something occurs, are you near populated area? So, to put this in perspective, and I'm talking perspective relative to fracking, according to the USGS, between the years one thousand nine hundred and seventy three and two thousand and eight, so thirty five years, there was an average of twenty one earthquakes of magnitude three and larger. In the central and eastern United States. This rate jumped to an average of ninety nine level three earthquakes between years two thousand and nine and thirteen, and the rate continues to rise. In two thousand and fourteen alone, there were six hundred and fifty nine magnitude three and larger earthquakes. To put this in perspective, like I said, magnitude three earthquakes are considered minor but can be felt by people at surface but very rarely cause any sort of damage. So one, level one, or magnitude one and two would be the lowest level of seismic event and cannot be felt a surface. Typically right around magnitude threes when you would start to f feel something. We're not talking your whole house shaking, but... could actually feel something. It's not really until you get to magnitude five where you can start doing damage and it's not really until magnitude seven, eight nine that results could become catastrophic. We're talking like movie, something you could see in a movie for an earthquake where it's leveling a whole city block or destroying a home. Those would be like magnitude eight nine to type of earthquakes. So governments aren't stupid. Most of the time they can see a trend in the increase in seismic events and that certainly coincides with an increase in fracking. They also know that the Publicans is concerned because of the increased attention from the media or social media. However, the oil industry is a significant source of jobs and revenue from taxes and royalties and things like that, so inevitably they have to find some sort of happy medium between oil companies and the public. This is why we're starting to see more regulation around seize mcmonitoring, which means watching for and recording the seismic events or earthquakes, and also bringing in consequences, which means shutting down operations if they if they're or if we're inducing earthquakes which could cause damage or harm to the public. So let's be real for a little bit here. We talked about magnitude one and two earthquakes or seismic events being basically insignificant. We talked about three being minor but you can feel something at surface, and we talked about it kind of when you start getting to four and five where there's potential. So a lot of the oil and gas companies that I know have adopted a system, and this again this is an areas where there is government regulation around this, but they've adopted what's called a traffic light system, and so it kind of the red, yellow... approach. And so the oil and gas companies will be monitoring seven while fracturing operations are going on, and they'll have the ability to monitor these seismic waves. As fracking is occurring at surface, they'll be monitoring it and these seismic events will be occurring. You might have a one point two and then a one point three along the surface of the earth as your for wing your well or wells. And so as these events are occurring, they're monitoring them and tracking them and as long as they're below a certain threshold, it's kind of the green light approach. So okay, we're monitoring them, but they're non significant events and we have the green light to keep going. If the fract job keeps going and you start to see the trend of seismic events increase or we start to see them get to a higher level, maybe something in the three range, three point one, three point two, then it's a yellow light approach and it's okay, guys, something's going on here. We're seeing an increase in trend. You know, the the magnitude of the earthquakes is getting a little bit higher. We're not above the threshold, but we're getting close, and so instead of just monitoring, then the team could start talking about how do you mitigate the risk? What can we do differently? Can we pump less propit? Can we reduce our rate? What are the certain ways that we can change the design and so that we can try and impact it so that there's less potential for these significant seismic events? And then, of course, there's The red light, and that is where the government regulation steps in and says if you record a seismic event, a single seizemic event, that exceeds a certain level or magnitude, and the level that I'm...

...familiar with this typically magnitude for then there would be a set procedure that you would have to follow before you can start your operations again, and typically that would be shut down operations, inform everybody of what's going on, sit down with your team and start putting together a mitigation plan on how you can change what you're doing, because of course you don't want to have any significant seismic events. So I think that's probably a little bit more detail than we needed to go into here, but it kind of hopefully helps you understand the logic or the process behind how this type of situation is managed, because a lot of the times in the media you hear about earthquakes and it's all this negative connotation and of course people naturally probably go towards the oil and gas companies fracking a well and it's causing a magnitude nine on the Richter scale earthquake that's going to level the entire community. Well, that's not true, but I think it's important for us to understand that these things do happen. The oil and gas companies do monitor them and do put in place processes to help mitigate them. There is government regulation around it and so it is a controlled situation, but certainly is there is some risk to it. So I think it's just important to understand both sides and how the whole process works when it comes to earthquakes or seismic events, because it is such a hot topic in the media. I mean it's really only fracking is really only become a popular method to complete wells recently, despite having been around for a long time. So as a result of this really the consequences of it are still not very well understood. The benefits of fracking are huge for the economy and employment, and it's...

...a big reason why the price of boiling gases come down so much in the last few years, several their decade really, I guess. Cheaper prices at the pump, cheaper heating bills for your house directly related to the increase in oil and gas supply generated by fracking. But there are downsides too, and size seismicity is potentially one of them. It is a risk that we know exists, but it's one that we can't exactly measure. We may know what's going on, but we don't know exactly what layers it's happening in, and that mostly because if we want to monitor it more, that accuracy, or that additional accuracy in terms of what we're doing, is expensive. So all we can really do at this point is do our best to understand the risk and minimize it we're acceptable, and eliminate it where it's not so really, at the end of the day, this is something that is part of fracking and so, like anything else that exists, if we can't eliminate the risk, we have to do our best to mitigate or minimize it, and so I hope I've done a good job in this podcast and educating not only what the earthquakes are and what causes them, but how the process works to minimize and mitigate that risk. Hey, guys, if you like today's episode, make sure you subscribe to the podcast. Unlike most podcasts that release an episode every week or two, I did all twenty four at once, Netflix style, so you can listen to them all right now if you just hit subscribe. If you like today's episode, make sure you leave me a comment or a thumbs up, or you can email me at from fossil to fuel at GMAILCOM or look me up on Linkedin. I'm Brendan McDougall.

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