Thursday, September 29, 2011

Tambora and Hierro - sleeping giants

Well, I was going to write a blog specifically about Tambora today, but the volcano world is abuzz with news about El Hierro in the Canary Islands (Spain). Both Tambora and Hierro have not erupted in recent times. Tambora last erupted in 1815 and killed nearly 80,000 people (although this number varies greatly depending on the source). Hierro last erupted in the 1700's, so there are no witnesses left alive that would have seen either of these erupt.

Hierro is an interesting monster. Its neighboring island of La Palma (also an active volcano), along with Hierro, have been responsible for some of the largest and deadliest tsunamis in human history. In fact, Hierro unleashed a 100 meter tsunami that slammed into the East Coast (New York area) about 10,000 years ago. La Palma is thought to be the biggest tsunami threat to the East Coast of the US, as the island has already begun to 'fall apart'. A huge fissure runs down the middle of the island, and GPS records about 10cm a year of motion into the ocean with the sliding land precariously waiting to catastrophically release. There is nothing that will stop this, and an eruption on La Palma will likely speed this process.

Hierro is a tourist destination, and as of this writing, approximately 53 tourists have been evacuated, and thousands of residents are preparing for what seems to be an inevitable volcanic eruption on the paradise island. Over 8,000 tremors have been recorded in the past couple months, and some articles are saying that elevated CO2 emissions are present in certain areas. The largest quake so far has been a 3.4 quake. Some residents are saying they can hear the volcano at night, with low rumblings underneath that get louder and louder. Quite freaky!

If Hierro blows, nobody quite knows what characteristics this eruption might have. The activity center appears to be within the collapse area of the 10,000 year old tsunami generating landslide. It looks like a half-moon shaped crater on the North West side of the island. This could also be a caldera. If it is a caldera explosion, or even submarine, the explosions generated could be quite large. However, Hierro has a long history of simply eruption cinder cones, and small lava flows... so time will tell. In any case, it is unprecedented in our history.

And in Indonesia, residents have voluntarily evacuated near Mt. Tambora, the volcano with the largest historical death toll in semi-recent history. Tambora is a large stratovolcano truncated by a 4.5 mile wide caldera. The shape is symmetrical and reminiscent of Oregon's Crater Lake volcano. But residents should not fear this volcano as much as they might, because the most damage it could ever produce has already been done. Likely, Tambora will see either phreatic (water hitting magma) eruptions and minor explosions, or an effusive, dome building event within the crater. The risk of a gigantic mega explosion (its last one had a VEI of 7 out of 8) is almost nonexistent, unless it chooses somehow to become a supervolcano, which will not happen. Or, Tambora might not even erupt at all. In any case, it is a spectacular volcano, and one worth checking out on Google Earth. News out of the region is spotty, so I am relying on reports from John Seach, the Smithsonian Global Volcanism Report, and other news sites I can find.

Hierro however, is probably the more exciting and scientifically fascinating volcano to keep an eye on, as it appears this volcano could erupt any day now. The quakes are getting more and more shallow, and residents are getting more and more nervous. They don't know where or when this volcano might have magma break the surface, the type of eruption that's in store for them, nor how long the eruption may last for. But it should be a spectacular display of nature's power, and people should take heed- just because a volcano has not erupted in a long time, does not mean it can't happen at any second. Fortunately for the residents of Hierro, it seems the volcano is warning them far ahead of time!

Monday, September 26, 2011

Volcanic Mechanics

So the last post sort of told you where I was going with this thing. There have been many reports in the news lately about volcanic eruptions, from Eyjafjallajokull in Iceland, to lesser known volcanoes such as Nabro in Eritrea (which had no prior historical records of having erupted). Due to the nature of the Internet, and the speed at which information travels nowadays, it could seem to the layman that volcanic eruptions, earthquakes, and other natural disasters are on the rise.

While it makes for good tabloid news, this is simply not the case. The earth has many, many active, and dormant volcanoes. They did not get to be the size that they are by being eternally quiet, sleeping giants. In fact, the very earth you're standing on was born of fire. This is a normal process, and if you look at the historical record of eruptions, you would actually see that eruptions are decreasing due to the cooling of our planet (obviously the surface is not molten, a result of our planet slowly cooling over time internally).

However, this does not mean that eruptions shouldn't fascinate, and even terrify you. Indeed there are some DANGEROUS volcanoes out there that should they erupt WILL result in mass casualties. Vesuvius is a murderer, and since its famed eruption in Pompeii, and the eruption of WWII, it has remained quiescent as the population grows around it. If Vesuvius has a major eruption, there is no possible way to properly evacuate the millions of people who live around it. The same is true for stratovolcanoes in the Cascades ranges, like Shasta, or Ranier.

Media coverage of volcanic eruptions has been made very easy with the advent and implementation of the Internet, cell phones, and bloggers around the world. Indeed, many reports are first hand, and accurate, however many are from areas of the world where there is no accountability for the things you write. The country of Niger recently had an interesting report of a supposed volcanic eruption in an area without any previous history of volcanic eruption. Reports turned out not to be true. There is another blogger who routinely spreads misinformation and uneducated guesses, and gets a lot of attention (dutchsinse), and recently caused quite a hubub when he claimed that the Pisgah Crater in California was in an eruptive phase. The USGS subsequently was 'forced' to respond to his hype, and publish *actual* scientific data to shut up this loon. Unfortunately he took this as a declaration of war on his ego, and decided to actually campaign against the USGS.

Understanding what constitutes a volcanic eruption or activity is key to making good reports, good predictions (although predicting volcanic activity is FAR from accurate at this point in our history). Bloggers like Dutchsinse have a knack for convincing themselves, then convincing the idiots out there that they are on to something that millions of dollars worth of seismic equipment and satellite monitoring somehow failed to catch. This is simply not the case. You'd have thought that a volcanic eruption just east of Los Angeles would be HUGE news, suspiciously, there is none... or maybe thats no suspicious at all given that the area has not erupted for over 6000 years. That's not to say an eruption can't happen or wont. Chaiten volcano in Chile erupted after over 8,000 years of dormancy, proving that point. But it erupted violently, and without any prior warning other than a few smallish tremors.

In any case, there are actually GOOD online resources out there for volcano monitoring and good reporters out there that are ACTUAL scientists and volcanologists. Some of the good resources out there have very close to real time updates, and some others mostly report on only significant eruptions. The Smithsonian (http://volcano.si.edu) has a weekly report of all new and ongoing activity. The Global Volcanism Blog is a fairly good one to read as well. If you're into Icelandic volcanic activity and were as fascinated by the unexpected eruption of Eyjafjallajokull as I was, then you might check out the blog of Jon Frimann (http://www.jonfr.com/volcano) who usually has a good number of articles on the current state of Iceland's volcanoes and fault lines.

When reading about volcanic eruptions there are several things to consider. Your source, you own background knowledge about the subject, and any motivation for writing an article. It's also important to filter out hype. Mainstream news media is NOT a good source for volcanic reporting as they often embellish speculative opinion, or attempt to have some meteorologist predict eruptions... all of these things should be ignored.

Volcanoes operate on many different factors, and it is important to understand the different types of volcanoes, and how they work. You have subduction fault volcanoes that typically result int he formation of a stratovolcano, like the kinds found in the Pacific Ring of Fire. There are hotspot and sea-floor spreading volcanoes that occur when a mantle plume breaks through the crust usually along a fault, such as in Iceland, or Hawaii. There are supervolcanoes, which much like the mantle plume type, have a large silicic magma chamber such as Yellowstone Caldera or Toba in Indonesia, which take a very long time to 'charge up', and blow. Then you have monogenetic volcnic fields like Michoacan-Guanajuato in Mexico, where numerous small cinder cones such as Paricutin erupt once, then never again. There are rarer types of volcanoes as well, such as Ol Doinyo Lengai in Africa which erupts carbonatite lavas, the only known volcano in the world that currently erupts these strange lavas.

The point is, knowing the type of eruptions your volcano is capable of having is important to cross referencing the validity of any eruption report. Although many times, a picture is worth a thousand words, an a video even more so.

My next blog posts will focus more on specific eruptions, and I will report on those citing viable sources.

Up next: Tambora Volcano, Indonesia's sleeping killer.

Friday, September 16, 2011

Volcanoes explained (for dummies)

Since this is the first post in what will likely be a long running blog, I'd like to introduce myself so you know who is writing these. I am a computer network engineer by trade, an amateur geologist by hobby. I have spent about the last 12 years studying volcanoes, tectonic plates, and the earth's core out of fascination with the subject. My goal here is to provide the public with a clear view of what our planet is really up to, minus the sensationalism, hype, and misinformation. I will site REAL sources of information in regards to volcanic eruptions, the study of volcanism, and earthquakes. I will however boil down most of the jargon for people who have not spent nearly as much time as myself studying the subject.

It is my hope that people can read these posts, and come out with a clear understanding of the world they live on, and the potential hazards, without the meaningless sensationalism that many news sites, and other bloggers impose on you to terrify, misinform, or use for political gain. I also aim to make this slightly entertaining, but not to the point that the science is obscured. That all being said, welcome to the blog, and I hope very much that you enjoy the read!

My first post is going to highlight GOOD sources of information in regards to earthquakes, volcanoes, and other geological forces of nature that are fundamental to understanding what our planet is up to. I will also highlight tactics that the media, and special interests use to twist these facts with opinion, innuendo, and religious rhetoric (all of which completely pervert what is a beautiful science). After these posts, news of current eruptions and earthquakes will be linked, explained, and analyzed!

Enjoy the fireworks!