Geologist Dr. Tamie Jovanelly will discuss the mechanics of a fissure eruption, highlight historical eruptions in Iceland that have had global consequences and explain the current volcanics on the island. Additionally, she will share why geologists all around the world are excited about the new scientific discoveries being revealed in the magma.
e e e e e e e e e e e e e e e e e e e e e e e e e e e e e e well good afternoon and welcome to uh another edition of our lunch lunch and learns I’m Dave dunde I’m Director of Education I’m so glad you’ve chosen to take part of your busy day and spend it here at my favorite Science Museum uh as always I’d like to tell you about exciting things coming up because we only do exciting things here at Tellus and uh next up uh we have a wildout weather day on uh July 13th uh we’ll have meteorologists from uh The Weather Channel here uh we’ll have uh meteorologists from uh WSB radio here and meteorologists from Georgia Tech here doing uh uh some talks and also doing uh some uh uh interactive activities out in our Great Hall and we’ll have some uh specific shows about weather in our planetarium our brand new projection system which is awesome if you haven’t seen it come see our planetarium it’s really great um also uh on in July we have our Building blast uh if you like rockets uh we have a a special Workshop where you come and build Rockets you hear from our NASA Ambassador about the latest NASA rockets and then you get to launch your rockets and take your Rockets ETS home with you what’s cooler than that really um our next uh lunch and learn on July 17th is on hydroponics and it’s a new industry that’s really coming to Georgia uh the future of farming may be inside and so uh talking about how this whole industry is is growing no pun intended uh uh and uh talking about how uh Hydroponics may be the future of where our fresh food may be coming from well today it is a great honor to to introduce a good friend to tell us uh she’s talked here many times before and she’s been very generous with her time and her expertise uh with our Museum uh Tammy jelli um is a uh an associate professor of geology at Barry College uh uh she received her PhD from Kent State University uh and her master’s from University of Nebraska uh she is an amazing person she travels uh to Iceland regularly she leads trips to Iceland if you want to have an expert geology trip boy Tammy’s the one to talk to um and uh she actually is embarking in a little bit uh on a 2-year road trip through Europe it’s it’s amazing so it’s hard to keep up with Tammy all the different things she that she’s doing uh but today she’s talking about her favorite topic uh Iceland and uh the land of Fire and Ice and talking about Fisher eruptions since uh 2021 so uh please give a warm welcome to Dr janelli thank you thank you let’s see let’s go back good afternoon thank you for having me thank you for the introduction um yes I’ve spoken a few times here at the Tellis Museum and it’s one of my favorite locations to be able to share my knowledge of a variety of different things so um again my name is Dr Tammy jovanelli I’m an associate professor of geology over at Barry College um and I’m also an international researcher and and author in uh 2020 I wrote a book for Wy about iand and it talks about a variety of different things but focuses on tectonics volcanics and glacier features so I’m excited to be here today particularly because there’s an active volcanism that’s happening on the island of Iceland it’s called a fissure eruption and so what I want to do in the course of the next 60 minutes or so is to give you some introduction to what a fissure eruption actually is and put it into some type of historical context whereby looking at past eruption so that we can make some comparisons about the the future and look at predictive models of what might what is yet to come but before I do that most people are interested as to how I ended up in Iceland in the first place so my first trip to Iceland was in 2006 when I was setting up a study abroad program for Barry colle College geology students and just like many of you that I’ve already spoke to in the audience once you visit Iceland once you always look for a reason to go back so I’ve been lucky enough to visit the island pretty much every year since 2006 and in doing that for more than a decade I decided that I had enough knowledge that I would write a textbook so I wrote an advanced geological Concepts book about the island again published by Wy in 2020 that focuses on the islands tectonics volcanics and glacier features and that’s really how I conceptualized the the island so the te is moving and Shifting the island it leads to the volcanism and then you have these things called glaciers that ruin it all and erase the signature but the the interplay between those three different systems have really fascinated me and continued to fascinate me when I was leading these study ofroad trips I would come back and parents would ask me Dr Joe when are you taking me to Iceland and so with that I decided in 2019 to start my own tour company and it was originally called Iceland geology tours but I’ve since expanded and rebranded to be called Adventure geology tours so we go to Iceland but we go to a variety of other different places with fantastic geology and it’s been so much fun to be able to take different people to visit these places that I love so much there’s one more thing that you need to know before we get started thank you Google and that is I don’t speak Icelandic as you heard it’s a pretty complicated Nordic language and although I practice with really good intentions I never quite nail it so I’m going to apologize in advance for my mispronunciations in addition because this is a talk on geology you’re going to see some acronyms on my slides that include M yo millions of years old M ya millions of years ago and the majority of the Drone footage that you’re going to see in this lecture today is part of my Personal Collection so you’ll get a glimpse of this beautiful landscape that keeps me going back every single year so we’re going to start uh with a discussion about the plate tectonics of the island so you’re looking at a modern-day plate tectonic diagram and we’re going to locate ourselves in the great state of Georgia and we’re resting on top of What’s called the North American Plate and if we go all the way up to 66° North we find the island of Iceland Iceland is approximately 38 miles south of the Arctic Circle is bordered by the Arctic Ocean to the north in the cold dense Seline Waters of the North Atlantic to its South Iceland is conveniently located on top of a divergent plate boundry so we can look at that purple North American Plate and just next to it is the orange Eurasian plate and so these two systems are pulling or spreading or rifting apart from one another another unique characteristic of Iceland is that there’s also a hotspot or a mantel plume and when we look at the geological history of Iceland this Hotpot begins to originate at the end of the last Pangia cycle approximately 50 million years ago so you’re imagining this body of magma upwelling from deep within the Earth’s system called the mantle and eventually at approximately 33 million years ago the magma begins to breach onto the ocean surface and it creates something that’s called the Icelandic basaltic Plateau which is the island of Iceland so if we look at the oldest ages of rocks Exposed on the island of Iceland they’re only 33 million years old if we consider the age of the Earth to be 4.6 billion years old Iceland has barely had a birthday and it is this dynamic system of Divergence that really impacts what we see on the island we’re looking at a map of Iceland and highlighted in red is the modern-day position of where this diverent plate boundary is on the right is that Eurasian plate that was highlighted in Orange on the previous mat on the left you find the North American Plate that was highlighted in purple when we look at modern day movement of this diverging system we find that these plates are moving apart rifting spreading at a rate of 1 inch per year or 13 miles per million years I’ll repeat that because that’s going to be part of your quiz these plates are moving or spreading at one inch per year or 13 miles per million years so there’s really an accumulation effect that we see as a result of PL tectonics in addition one of the other amazing things about the island is that we can look at a lot of active volcanism so when we focus our attention on this map we can see the position of some of these volcanoes Iceland is about the size of the state of Virginia Iceland is about the size of the state of Virginia but contains 33 active volcanoes what Iceland that’s about the size of Virginia contains about 33 active volcanoes so anywhere you look in the landscape you’re going to see an active volcano a dormant volcano or some type of volcanic feature and that’s why really why volcanologists are so excited about this Dynamic landscape you’re focusing on this map of Iceland you can see the numbers and position of those 33 active volcanoes so I’m going to have you look close and hopefully when you look at this map you’re going to tell me that a pattern has begin to emerge relative to where the position of these volcanoes are and what you’re going to tell me is that Dr Joe the position of these volcanoes outlines the position of the divergent plate boundary and that surely makes sense doesn’t it so when you have Divergence and pulling apart you’re creating a conduit for magma to more easy come up to the Earth’s surface so the position of the active volcanoes is also the position of where that divergent plate boundary is when we talk about volcanism on the island of Iceland we separate them into three major parts so we talk about them in terms of the northern volcanic Zone the Western volcanic Zone and the Eastern volcanic zone so we separate them really into three major major systems at modern day some of the biggest and baddest volcanoes on the island of Iceland and arguably in the world are located in the eastern volcanic Zone and I’m going to call your attention here to number 15 her name is catla and we’re going to come back to her but the volcanism that we’re seeing in 2024 and really since 20121 is on this location that’s called The Rainy Peninsula and this ranes Peninsula represents the Western volcanic Zone the volcanism that we’ve seen for the past three years are classified as what we call a fissure eruption so what exactly is a fissure eruption fure eruption by definition occurs when these linear underground passageways called dkes gets infilled with Magma and when we’re looking at these fissure eruptions we separate them into two distinct categories and I I would love for you to pay attention to these two diagrams because this is going to continue as a theme throughout the presentation so this first diagram is what I’m going to call and refer to as scenario one and what we’re looking at in scenario one is you have this magma Reservoir that’s that’s connected to the mantle so this magmatic material that’s coming from deep within the Earth system is filling that magma Reservoir in scenario 1 however this Reservoir is connected to a magma chamber and that magma chamber is underneath a central volcano when when the magma chamber fills it will infill this linear subsurface Dy system so in this scenario one we would call these predictable and the reason why we call these predictable especially in Iceland is because we have a really good handle on the size and the shape of these magma Chambers underneath these volcanoes so if you know something about the size and the shape of the magma chamber you can anticipate how much volume of magma that they can hold so you can make some predictive models of how long it would take for these linear Dy systems to infill in addition we call them somewhat predictable because these magma Chambers and Dyke systems are relatively shallow below the surface they’re only about 2 to four miles below the below the Earth’s surface so we can instrumentally m monitor them and as a result when we look at scenario one especially in places like Iceland these are really good regions to harness geothermal energy because they’re predictable and because the heat is so shallow towards the Earth’s surface moving into scenario 2 you can have the presence or absence of a central volcano but more importantly we’re focusing on this magmatic Reservoir that is directly connected to the linear Dy system the magnetic Reservoir in scenario 2 is directly connected to the Dyke system so what that means is that these are unpredictable and they’re unpredictable because theoretically you have an unlimited supply of magma that’s in direct connection with these linear passageways in addition they’re also considered to be unpredictable in their nature because usually in scenario two these Dyke systems are much deeper so they’re much harder to instrumentally monitor when we talk about fissure eruptions we refer to them as something that’s called a fissure swarm here again on the screen I have this map of the position of where these 33 active volcanoes are and we said that they are correlated to the the position of where this divergent plate boundary is happening but on this volcanic map I want you to focus on the position where these red dots are and each of these individual red dots that represents a central volcano scenario one now if you focus your attention on these um areas of light blue these areas of light blue that are also numbered those represent scenario Ario number two so on this map of volcanism we now can understand that 14 of the 33 volcanically active areas in Iceland are designated as fissure swarms so half about half of them represent scenario one and about half of them represents scenario 2 if there is a central volcano the fissure swarm will be named after the volcano if there is not a central volcano the fissure swarm is still in and of itself named as a system there’s a few precursors that can be uh monitored that are precursors to understanding when a fissure eruption will occur so the first thing that we can think about is looking at how the ground surface changes when you have either scenario one or scenario two you have magma that’s moving up through the system from the deep mantle and it’s infilling these cavities and as you can imagine when those cavities that are underneath the ground surface get infilled you’re going to have inflation because you have the proximity of this magma that’s moving closer and closer to the Earth’s surface it’s taking up space so one of the things that um the Iceland meteorological office monitors in the Iceland Met Office is equivalent to our United States Geological Survey so one of the things that they monitor all around the Rainy Peninsula and other places in Iceland is the the ground surface so if we look at this first diagram on the x axis this represents days and on the Y AIS this is going to represent a distance from a a ground surface so it’s going to represent how the ground surface is increasing over time so for one of the fissure eruptions in 2023 we’re looking at a data set and what you can realize is the ground surface is flat and then all of a sudden you get an increase in inflation this map represents an inflation of of almost a foot and a half but it can be it can be much more and as that magma is moving up to the surface eventually the magma will breach there’ll be a crack or a fissure the reservoir the Dyke system will empty and then the ground surface will go through deflation and so deflation is is as equally as important as inflation because you want to have an understanding of when the Dyke system has end emptied because that’s going to indicate when the process theoretically has ended when your when your um when your system has been complete and all of the magma has reached the surface so the conclusion of the volcanic episode so we can look at inflation as a precursor to indicate when we think these things are are going to start but we can also look at size it and what we said is that there’s a divergent plate boundary that’s ripping apart this island nearly in half so there’s always lowlevel seismicity that’s always happening on the island of Iceland there’s always lowlevel magnitude two magnitude 3 earthquakes that are happening but prior to a fissure eruption more important than the intensity will be the quantity of of earthquakes that happen so this again is the Peninsula this is a data set from 2023 from the Iceland Met Office that correlates to the previous diagram and each of these individual dots represents an earthquake so prior to a fissure eruption it’s not uncommon to get like 10,000 earthquakes that happen and that makes sense too doesn’t it because this magma is moving up into the Dyke system through cracks and crevices and it’s trying to find the the path of least resistance and as it does that it’s fracturing The Rock and giving off energy so we can look for the ground surface to inflate and then we can also look for earthquake activity particularly earthquake swarms that happen so when that magma finally breaches you have a crack literally literally a crack or what we call a fissure that opens up in the Earth’s surface it allows for a conduit from magma to come from that dyke gently to the surface so in Iceland um this type of material is called Basalt when it solidifies it’s a type of ous rock very similar to what we find on the Hawaiian Islands this type of magma has a low viscosity or a low resistance to to flow in geology we term we use a term called effusive the magnet is effusive so it’s gently coming to the to the landscape and in Iceland usually when visure eruptions occur these are called tourist eruptions and the reason is because this magma is so gently coming to the Earth’s surface you can get in pretty close proximity of them so the limiting factor to getting close to these systems usually and especially if gases are not being emitted that’s my husband at least he cooks me dinner right so these are called tourist eruptions because you can get so close to them usually so the limiting factor is really the proximity of heat that you can tolerate other things is um a t this type of tourm is is usually encourage in Iceland and that’s because um these These Are So Beautiful they really want the government of Iceland and the Met Office really wants people to enjoy them and enjoy them safely so they’ll have people going around and monitoring for gases because that’s the the limiting factor on really how and if you can enjoy these types of of events now what’s fun to think about is that when we consider um Iceland and what we said was that it’s 33 million years old what we know is that there’s always been a divergent plate boundary and there’s always been a hotspot therefore there’s always been active vulcanism on the island of Iceland uh as an example when we consider what we call the Repose or the recurrence interval of a of a volcanic event on Iceland we say that there is activity once every five years so if you’re lucky enough to meet somebody who’s lived on the island for a hundred years they’ve experienced at least 20 different volcanic events in their lifetime so the Vikings show up in 874 CE they um they begin to build their homesteads and what’s fun to think about is that the Vikings in 874 CE were seeing things that we are actually seeing today literally on the island of of Iceland so when the Vikings write about the island in their sagas they talk about these types of eruption being fires or they talk about them being curtains of fires and when we look at this picture that makes a lot of sense doesn’t it so it’s a visual representation of what we’re seeing and a shared connection to the Vikings that established themselves in 874 CE now um when they settled they were um initially pagans um they later switched to Christianity but when you read their writings the Vikings certainly were not afraid of the volcanism they realized that that is a natural process and remembering that the Vikings initially were nomadic so if there was a a fissure eruption that was causing the too much of a problem they were able to to move away to another part of the island the benefit of being in an area of fissure eruptions is sometimes you get geothermal heated pools so they had to make a decision as to whether to stay or whether to to visit but the whole perspective of the Vikings was thinking in terms of their con connection with the natural environment recognizing this is a natural process seeing them once every five years and just knowing that this two shall pass when we talk about fissure eruptions they don’t form a central volcano instead what they’re forming are these things that are called Vents and this is a a video from the bab Boomer eruption in 2019 so in this video you’re seeing the two different vents that are forming and so you’re imagining you have this crack and you have these areas of concentrated lava flow so just these areas along along the fissure where pressure has um has risen and that’s creating the magma to come up at a at a specific location for a specific length of time we can also call these vents they’re sometimes referred to as spatter cones and the reason why they’re called spatter cones is if you look close it there’s tiny pieces of magma that float into the atmosphere and they cool as they fall down to the to the surface and so along the central vent of a spar cone you find a deposit that’s called tefra and so essentially the tea is just tiny tiny pieces of magma that’s cooled and it’s cooled as these tiny pieces of Basalt so they become unconsolidated around the central vent as they’ve been spattered out onto the Earth’s surface and cooled in the media um when these types of fissure eruptions are described um we like to talk about two specific things we talk about the fountain height and so the distance of How High the magma is uh approaching the surface that’s called The Fountain height and then we also like to talk about the discharge and the discharge is how quickly the magma is Flowing on the Earth’s surface so it kind of depends on the intensity of the eruption and the intensity of the eruption will largely depend on how much magma is is stored in that dyke system and it’s also considered on how long the event has taken place so looking at the duration so intensity and duration usually go hand in in hand and if we’re thinking about duration fissure eruptions are are are unpredictable because they can happen over the course of a day over the course of weeks over the course of years the course of decades and even the course of a of a century so what I want to do now to put this in uh some type of of context for us is I want to talk about three really well documented historical fissure eruptions and this will give us some perspective to make comparisons of what’s Happening literally today so the first one is called the called the meaan fires named by the Vikings that occurred from 7 1724 to 1729 the meot fires occurred over the course of five years and they occur in the northern volcanic Zone highlighted with this star here you might be familiar with the term meat if you’ve been to Iceland because there’s a pretty famous Lake there lakes in Iceland are relatively unusual they’re either formed by divergent plate boundaries that create a basin or there’s lava flows usually f is eruptions that help to create a basin and that’s what we find in in the lake Moten region so 800 years after the the Vikings settle there is an a fissure eruption along the cfla fissure and we have a central volcano her name is craa she initiates this linear Dy system and and um and movement called the fissure eruption cfla is one of five of these fissures in the northern volcanic Zone and so remember what we’re thinking in terms of is scenario number one so you have a central volcano and then you have this lateral Dyke system that’s being fed by by a magma chamber so over the course of eruption this um this area was really monitored by a pasture who is living along the lengths of of MOT and and he really noted drastic changes and specifically on how the Basin was was changing um over the course of these 5 years it brought to the surface about 18 square miles um change again changing this shape of lake moton and what he writes about is how five different homesteads were annihilated so they were overcome with with u with lava and that was a a pretty uh distinct portion of his his manuscript but what you notice in this picture is that you still see the remaining church so if you visit Lake meaton you can still see this structure so it uh it still stands maybe through prayer but probably because it’s on elevated topography so you’re able to visit the structure from the 1700 which is pretty un unusual on the island of of Iceland if you if you go there so we have the mot and fires lasting five years we fast forward to to 1783 and this is where you’re going to buckle your seat belt because in 1783 we’re going to see the evidence of what we call the lacky fires get ready for this folks Lackey fires June 1783 to February 1784 over the course of nine months there’s going to be a fissure eruption that’s going to be considered Iceland’s worst natural disaster in historic time and not only is it going to influence the island of Iceland but it’s going to influence Europe and it’s going to have Global consequences and this is again a fizure eruption that only last nine months this is what uh icelanders write about in their history books and they certainly continue to to to teach their children and their history classes lacky fires occurs in the Eastern volcanic Zone and um lacky fires are the result of the volcano number 15 here called catla so again we’re thinking scenario one and what happens over the course of these nine months is that a crack in the earth’s surface is going to open that’s 15 miles in length what over the course of nine months a crack in the Earth surface is going to open it’s going to be 15 miles in length and along that crack that’s in the interior of of Iceland within the Eastern volcanic Zone 130 of these different vents are going to form along this very linear feature and I really appreciate this Photograph it’s from Thor thoris he’s a um a foundational Icelandic geologist who studies Lackey crater he wrote a fantastic paper that was published in 2003 and I highly recommend you take a look for that on Google Scholar if you want to know more this aerial photograph of um Dr thoron gives us a perspective of the linearity of these crater systems so what happens when you have a crack 15 mile long that brings and produces 130 different vents it brings to the surface about 42 billion tons of magma this is going to be the second largest historic eruption in Iceland so there’s consequences when you bring so much magma to the surface but what is different about the Lackey fires that’s going to be different than any of the fissure eruptions that we talk about today including the one that’s occurring now is that the lacky fires occurred um in the Eastern volcanic Zone but it was on the the western side of v and jokul so vac and jokul is considered to be Europe’s largest remaining glacier and when we look at the Lackey fires which is highlighted in pink the fissure where the the place where the fissure was what happens is when you have magma that intersects glacial melt water you intensify the eruption so magma mixed with water produces something called a ftic eruption and so in this area June 1783 you get a massive eruption of the surface that produces a lot of volcanic ash and this volcanic ash is going to cover about 90% of the island so when we look at this map of map of Iceland the orange represents the proximity of where that volcanic was so other than really the Western fiords the majority of the island is covered in this volcanic ash but wait there’s more so not only are we dealing with volcanic ash but the big problem is that this particular eruption contained fluoride and what we know is that when Ash goes up Ash falls down and so 90% of the island is now covered with this contaminant that’s going to seep into the groundwater is going to get into the surface water the cattle are going to go try to graze so they’re ingesting the fluoride and then the sheep and cattle are going to come down with fosis the people are going to come down with fosis from eating the cattle ingesting the water and remember this this activity went on for 9 months so you have a lot of gases going into the into the atmosphere you have water vapor carbon dioxide carbon monoxides and abundant particularly with this eruption of of of so SO2 so when we look and call this Iceland’s worst natural disaster it’s because 1th of the population passes away within the course of 9 months and then what tends to happen is because they’re still you’re still dealing with all of that volcanic ash famine is going to widespread over the island 1783 folks the population isn’t all that big so this was a huge hit to the population density of the island this is what happened in Iceland but guess what that volcanic ash moves to Europe and here we’re going to see some more consequences so when you have particularly SO2 that goes up into the atmosphere when it mingles with water vapor there’s a chemical reaction and so what ends up being produced is sulfuric acid h2so4 and re remembering we’re talking 1783 folks there’s not internet there’s no phone call there’s no texting and so the people of Europe are going about their daily habits and they’re noticing this acid Haze that they write about so what’s going to happen is that that sulfuric acid is going to come down it’s going to completely devastate their crops and Institute famine throughout Europe to the point where where even it’s thought that perhaps the French Revolution might have been instigated by the Lackey fires because if we know anything about the French Revolution people were very hungry and there was end up being a Revolt so perhaps the lacky fires contributed to to um to big and lifechanging um events happening in Europe 120 megatons of suric acid aerosol was released over the course of 10 different episodes but wait there’s more so when you have a volcanic event usually we talk about these gases I mentioned water vapor carbon dioxide carbon monoxide so SO2 we categorize them as a greenhouse gas so usually we associate them with a planet warming however again when you have SO2 in all this water vapor from the significant eruption going up into the atmosphere you’re producing h2so4 sulfuric acid and sulfuric acid is actually an inhibitor to solar radiation it doesn’t let the heat in it blocks the Sun and so globally when we look at data during the the five years after the lacky eruption temperatures decrease almost 5 degrees Fahrenheit Global consequence is associated with this particular fissure eruption it’s fun for us to look at this data this was published Again by Thor thordson in 2023 and he’s looking at um at time he’s looking at specifically winter temp in the eastern part of the United States where we are and so there’s a distinct um distinct drop in temperature uh at about at in and around the Lackey fires more important to us in the eastern United States is that that decrease in temperature in winter temperatures is the difference between 32 degrees Fahrenheit freezing or being above freezing so again worldwide famine could have been instituted by the Lackey fires that happened only over the course of nine months moving forward in time really Iceland in terms of fish eruptions were um were quite stable um the next big event that’s going to happen is going to be in December of 1975 these are called The Craft LIF fires and they’re going to last all the way until September of 1984 so they’re going to last for 9 years years and over the course of these nine years there’s going to be about nine different episodes this is in the northern volcanic Zone again and so we already talked about cfla right scenario number one where you have this linear uh Dyke system off that Central volcano magma chamber so 250 years after the meon fires we see some activity uh again what’s important about the crafta fires is that when we look at the duration of these events they’re really short they’re on the order of days so the first event is going to happen for for two days and then we see three days and the very last event that happens in September of 1984 is going to go only going to last just over two weeks so it’s going to last about about 15 days so we’ve gone from the meot and fires that consistently erupted over the course of 5 years Lackey that erup erupted intermittently over the course of nine months but had significant consequences and then we see this decade almost this decade long event that happens just very short over the course of a few days at a at a time another thing that’s important about the crafta fires in the in the northern volcanic zone is that what we said about scenario one was that these Dy systems are really great for harnessing geothermal energy because those Dy systems are close to the surface between two and four miles deep and so they recognized this in Iceland in and around December 1975 they were planning to open their very first geothermal energy plant but then there starts to be fissure eruption so they had to ask some questions as if they wanted to proceed with a building and proceed with the opening but in true Viking fashion they recognized if you can’t beat it join it you might as well monitor it and that’s exactly what they did so they went ahead and they opened up this plant they made it through the ciers and this plant is still in full operation today this event is important because this is the very first instrumentally monitored fissure eruption in Iceland so when we talk about those inflation and deflation models and this idea that a lot of earthquakes swarm before the fissure opens we know that from this monitoring and we know that because they were trying to protect their geothermal energy plant that they had just invested a lot of money in so where are we at today today there’s activity on the rain East Peninsula which you’re seeing in this map here and I’m going to give you this position here which represents the capital city of rovic and then the second star is going to represent kvic kic is where the international airport is so if you fly into Iceland you will fly into kic and you’ll take a boat about one hours to the north to the city of rovic but when we zoom in on this area of the Raines Peninsula what you will notice is that you see these linear systems these are fissures these are fissure swarms and each of these fissure swarms there’s six of them are in eelin to one another each of them have their own specific name name what you also notice on this map of these of the Raines Peninsula you notice that there’s not Central volcanoes so we’ve talked a lot about scenario one but what’s happening on the Rainy Peninsula today is actually scenario 2 so we are thinking in terms of this deep-seated magma that’s infilling a reservoir that’s directly connected to these linear Dy systems that are are a bit more unpredictable as a result another thing to highlight on this map is that you have this hash line that hash line represents the divergent plate boundary so on the rain East Peninsula we refer to this area either as the Western volcanic zone or we call it the the Rainy volcanic belt but because you have that divergent plate boundary again there’s always low-level seismicity I don’t know that I’ve ever been to the capital city of raikov and haven’t felt uh an earthquake although they’re low level so they’re a magnitude four or or less so we have six different fissure swarms on the rain East Peninsula and the last time the most recent eruption was about 800 years ago and this is termed the Raines fires the Rainy fires occurred from 1210 to 1240 it lasted three decades and It produced It produced this feature called Stamper crater row so I showed you earlier the creation of these vents in that babonga 2019 eruption this is what they look like solidified you’ll notice their linearity off into the distance so they’re following the the fissure system not nearly as extensive as Lackey crater with 130 different vents but certainly a dramatic site for these Vikings to actually witness another thing I want to call your attention to is we talked about these being called either vents or spatter cones and we call them spatter cones because this is that loose uncol unconsolidated pieces of of tea so that as that magma was going up it was Cooling and falling so you can still see that around these these vents even though they are 800 years old the people are nice for scale too so this is what you get into if you’re looking at the Rainy peninsula so when we T talk about um this more modern activity we say that this particular fissure swarm is called faral FAL and so we’re looking at this particular fissure so a different one one of the six and the last time that this fissure was active was about 6,000 years prior so activity on the Raines Peninsula only about eight years ago this particular particular fissure has been dormant for the past 6,000 years and the first time it started to wake up was in 2019 the first eruption that occurred was in 2021 so on the Rainy Peninsula and really in all these volcanic regions the Iceland Met Office is monitoring for inflation and they’re monitoring for increases in in earthquake activity and that’s exactly what they saw in this region starting on March 19th in 2021 so this event is only going to last on the order of of nine months the good news is is that in this particular fissure swarm this area that’s approximately 18 miles outside of of the city of rovic the capital city is largely uninhabited so largely uninhabited so this particular fissure swarm was truly considered a tourist eruption when we look at this topographic map you can notice that if you’re willing to do the hike in there’s a lot of places that are elevated so if the Contra lines are closer together that’s going to indicate a hill there’s a lot of places where you could magically get up and you could view the this Dynamic process as the fissure opens and brings magma to the surface and what we said is that the magma is a fusive a low viscosity low resistance to flow and so what it does is it just really follows the topography if you choose to study these fissure eruptions a little more deeply what I want you to recognize is um is their naming practices so this these eruptions are either going to be named by the fissure swarm faral FAL but usually they’re also named by the location of where the fissure opens so in this 2021 eruption the first eruption fissure opened in glender Valley so it’s named after the after the valley so over the course of nine months in purple what you find is a lava field that’s about three square miles about three square miles and I’m going to show you um this other map which indicates the areas where these vents open there are six different vents that were created and they were up here on the left side of your diagram and because they’re so concentrated this is where the thickest part of the deposit is so the thickest part of the is about 400 ft thick and I want to show you a drone video that my wonderful husband took starting from the Star so he’s going to fly up Valley so we mentioned this area is largely uninhibited yeah yeah but what stunning landscape so the black represents the 2021 lava flow you can imagine this being a lava waterfall you can look at how these Peaks are elevated right so these are areas of higher topography where the lava just goes around them of to the distance you can start to see some of those vents that have formed during the 2021 eruption so moving forward the following summer there is also activity in faral FAL again the yellow is going to represent that 20 uh 2021 3 and a half square mile lava field the fissure is going to open just to the North in 2022 it’s not going to last for very long long it’s going to last for under a month it’s going to bring about a square mile of of magma to the surface the good news for me was that I was there leading a group of um for the association for women geoscientists we just took two tours around the island and we ended with these spectacular views of the building of some of these craters I like this particular view of the vent that that goes into slow motion because it really gives you an idea of that tea That’s Falling to the surface cool slowly as Cinders and then will be preserved as an unconsolidated Mass so but wait there’s more so in in 2023 almost exactly to the date another fissure opens in farra dfal just further to the north so up here will be a small crack on the Earth’s surface along that fissure swarm but look at this the the uh flow rate has drastically increased from its Inception so it’s so in 2021 the flow rate was around 300 cubic feet per second in 2023 the initial flow rate 1,800 cubic feet per second is there a correlation between the amping of magma coming to the surface prior to the conclusion of an event still that’s still being determined but there seems to be a correlation that you have a low intensity and then you end with um with a much bigger event it doesn’t last for long and eventually this 2023 eruption will flow down toward merod dollar Valley this eruption is referred to as little her or little RAM and again it’s they’re naming it based on the topography so this is a hill here that’s called little her and we were lucky enough to be there again for this eruption so this is Joey’s Drone footage he’s going to get confident and get close to this crater we now have insurance on our drone and we’ve used the insurance but look how stunning this is so this was on um the 21st so this was really at the beginning of the creation 10 days after the initial opening um near the Central um vent you’re often you have a Lava River and that’s what you’re starting to to form here you’re seeing the edges of where this lava flow we’re up on a hill and again we’re away from the wind direction you can see the direction the wind is blowing so we’re in in safety and again the Iceland Met Office circles around and they have monitors to tell you if you need to to to move along looking for carbon monoxide SO2 Etc off of the distance you see fire but that’s really the the lava F field meeting the mosses and so it start begins to start to to burn if you haven’t experien a volcanic eruption I certainly hope you do it’s completely sensory so particularly in Iceland you have um you have breezes that come off the ocean that um have uh condensation it falls on top of the lava field the lava field begins to sizzle it kind of smells like charcoal and obviously like they’re they’re truly beautiful so this if you’re going to hike all the way to see uh this volcanic eruption you’re going to day for the real show so this is the same day but this is just at night it’s the same vent and what’s starting to happen up here is like you start to have a breach eventually this uh sidewall will collapse itself so you can uh we talked about the fountain height you can see the increase in discharge the temperature of the lava um is different depending on the color so if it’s more of an orange color the temperature is about, 1600° fah and when we look at this particular eruption um what’s starting to form is a lava tube so the the the basalt layer that was there that solidified was eventually eroded by this hot magma is remelted so you’re building a deep Channel and then eventually the surface will insulate itself and you start to see the darker areas up here that start to form and then eventually you can form a a complete lava tube beautiful you can start to see poy Hoy structures here starting to form too Joey’s getting a little confident I see we’re going closer to the crater so what does that mean for for U for volcanism on the rain East Peninsula today so in starting in uh December just before Christmas there was another fissure eruption oh there is another fissure eruption that uh that opened but this is in a different um this is in a different fissure swarm so so we so from 2021 to 2023 we were here and now we’re in the sarasen Getti fissure swarm so we’ve moved some proximity to the West so this has been reactivated the difference between these eruptions is that while the first eruptions in farad FAL was uninhabited now we’re um having activity that’s closer to the city the city is called grenic there’s 3,700 people that live in the city and on December 18th when the fissure opened it was approximately two miles just north of the of the town so the lights represent the perimeter of grenic it’s a fishing village with this particular event that lasted about a month two more fissures opened another big difference is that this is lowly topography again aiding to aiding to its unpredictability because instead of having a nice channel that can be infilled it is a wild card where the lava will go um during this eruption um there’s a quick movement to make barricades along a hydrothermal plant and that’s because this is where the water hot water for the city of ravic is generated there’s about 200,000 people that live in the city of of rikic so they quickly made barricades to protect the hydrothermal plant in this event four houses were lost they’ve made some um important zoning Maps so people are aware of the danger they um they go through periods of evacuation and again um it’s important to look at these inflation and deflation models so since December these red lines indicate new fissures that have opened so there have been about five different fissures that have opened in proximity of grindvik within the sarti fissure swarm it’s currently erupting the total is about 9.2 Square kilm since December so the lava field continues to grow even today um what you should notice is that um is that each of these events have been building so the ground surface will build there’ll be a fracture and then it keeps on um going through these repetitive inflation and deflation models but what we also know is that it’s probably not that end of its like cycle because it the subsurface hasn’t gone through collapse yet so it hasn’t completely gone through deflation since December the city of Iceland has then been able to build barricades to protect their City centers and in and around so trying to redirect where the position of the lava flow will go to try to protect some of the structures that are in place however um here here’s a a recent a picture from early in June where the lava flow is going over the the road there’s not many roads on the Raines Peninsula so it’s pretty important to try to keep these roadways open and they do the best they can in trying to um immediately cool the lava lava by bringing in water from the ocean to exacerbate the cooling process and again trying to redirect it away from infrastructure so where are we at now so what I mentioned is that this is a pretty exciting time for volcanologists for a variety of different reasons one of the the big reasons and interest of study and the push to learn so much from these fissure eruptions on the rain East Peninsula is well they haven’t happened in 800 years so that’s really important but also this is the first time on the island of Iceland that magma in scenario 2 has been um has been measured the fissure eruptions in scenario 2 have been measured measured we talked about cfla 1975 to 1984 that was in the northern volcanic Zone that was scenario one it was tied to a central volcano the magma looks a lot different because there’s been mixing here when the magma comes to the surface you’re seeing a direct image of the magma that’s coming from the mantle before it cools how cool is that so so one of the um the the great papers is by benman that was published in 2022 too what we’re looking up here at the top is a cross-section from the Eastern volcanic Zone through the Western volcanic Zone and across the rain Peninsula one of the interesting things about Iceland is that the magma is so heterogeneous it’s still a really big question mark you have the influence of a hot spot and you have the influence of a divergent plate boundary but you have some weird uh chemical compositions of of magma even between the Eastern volcanic Zone and the Western volcanic Zone zone so when B bman was sampling that um that magma when you look at the the geochemical properties of it it gives indication that this magma is coming from about 10 to 15 miles below the surface if you remember from geology 101 you might be familiar with the terms lithosphere in asthenosphere so lithosphere is the crust and the upper mantle and the asthenosphere is below the moho line and so so it’s thought that this this um magma is coming from the asthenosphere below the moho line which is really exciting and impressive to begin to begin to look at now in conjunction with that um there’s a research group and this paper is by call 2022 they’re looking at the specifics of of these basaltic um these basaltic magmas and in this picture what you notice are these crystals so these are cryst crystals of Olivine and crystals of pelagic felar so also from geology 101 you might remember Bowen’s reaction series so Bowen’s reaction series tells you um how hot the magma is to form specific types of of minerals so when we look at Bowman’s reaction series when we look at Olivine Olivine crystallizes at400 degrees C plag clays belar that’s calcium rich also crystallizes at, 1400° C so this confirms what bman suggested that this magma is coming from a really deep source and the other thing that was confirmed is that this magma is very similar to what you find on the Rainy Peninsula this is cool too so kette all age dated these crystals so they isotopically took an age of the crystals and they find out the age of the crystals are 2 years old so what that means is that this deep-seated magma was probably stored in the subsurface Dyke system for at least two years and what we said if we back up is that in 2019 the Icelandic Met Office started to see inflation and they started to see earthquakes begin so what the data is trying to do is it’s really trying to to figure out the plumbing of this scenario 2 system that hasn’t been studied before because they want to be able to protect the city of grindvik if you know how much storage is there and you know how quickly the reservoir gets infill maybe you can make some predictions as what you expect to happen in the future and so what what will happen in the future and talking to um my great friends in in Iceland today the city has been uh evacuated and again they got the Iceland Met Office goes back and forth as to whether there’s letting people back into their homes this is not considered a tourist um destination tourists are not welcome because they don’t want looting to happen like they want to keep people away from the the the houses and likely what and what has already started to happen is that the Iceland government is allowing people to sell their houses back to the government so the government is giving fair price for the houses to encourage people to move what may happen is they might pick up the entire city of grindvik and put it somewhere else so we’ve got the displacement of about 3,700 people um it’s a fishing Village it’s been established a long time will they stay on the Raines Peninsula what you know is that there’s six different in Echelon fissures usually when one gets active it can kind of trigger another one so that might not be the best case perhaps they move the fishing Village somewhere further along the southern coast but I think it um it gives us um a really good example of how much the government cares about the people and they’re willing to help them to to resettle and give them fair and Equitable prices for the houses in order to do that so I thank you for your attention the land of Fire and Ice is waiting for you I’m happy to answer your questions and comments if you haven’t got enough of of me I’m a featured host on a show on The Weather Channel that’s called the Earth unlocked season two is uh re-airing season 3 will be released on January 14th um if you’d love to go to Iceland I would love to take you well thank you so much Dr Jay that was great I think everybody love your your talk and um the um we for all your all the junior GE geologists out there we have some activities over here my staff has on volcanos and I know Dr G vanelli’s got some touch pieces up here she’d love to talk about if you’ve got some questions for her uh she’ll be uh hanging around up here up at the front and thank you so much for coming to our lunch and learn thank you thank you very much that was wonderful good I’m glad you enjoyed it