Volcanic eruptions and fumes, oh my!

5 09 2008

The night after I helped set up the time-lapse camera to record any collapses of the vent rim, there were two magmatic explosive events. The rim area beneath and to the east of the plume is littered with spatter material. The explosions happened about an hour after I visited the visitor overlook. If only I’d been an hour later! At any rate, I was able to go down into the caldera again yesterday to assist with sampling gases from fumaroles. These are holes in the ground near volcanoes that emit gases and steam. We decided to see the spatter material before venturing in on foot.

Let’s just say it’s a good thing that this road is closed to the public. Some of the ejected material was incandescent at the time of eruption, which signifies fairly high temperatures.

We left that area and journeyed to the less-travelled southern end of Halema`uma`u crater. Here’s a view of the crater wall that you can’t see from the Observatory or Jaggar Museum.

We continued hiking around to the western edge of the crater and stopped for a bit to watch the plume. The vent was making banging noises like it had all day on Tuesday, and after a while it switched to gas rushing sounds. It’s akin to the noise a 747 jet makes as it lands. At one point the plume almost died out, and then it resumed more vigorous puffing and turned brown.

Our resident gas geochemist was nice enough to model for me.

He’s standing in an area of the crater known as the Postal Rift. When Halema`uma`u was filled entirely with lava back in 1919, visitors could walk right up to the rift and dip their postcards into the lava. The edges would become a nicely singed, unique souvenir of their visit to Kilauea. Try to imagine that whole crater and the rift where the scientist is standing as a lava lake. Pretty amazing.

So, I’m sure you’re all curious about what sulfur dioxide does to the areas surrounding it.

It makes sulfur crystals! When sulfur-rich gas seeps out of the earth and the area remains relatively undisturbed, it gives sulfur crystals the chance to grow. They’re beautiful.

Here’s a fumarole up close and personal. The crystals are about 1/2-3/4 inch at their longest. They also smell like rotten eggs. Hey, perfection is hard!

This is what we do with fumaroles…we sample the gas they emit! I’m using a technique called evacuated-bottle fumarole gas sampling. First we measure the temperature of the fumarole using a probe. The temperature around the crater is right near the boiling temperature at this altitude = 94.8 degrees Celsius. After that we insert a teflon tube into the fumarole, and connect the tube to a specially-made vacuum-sealed Pyrex bottle. We then pump the gas into the bottle slowly, and make sure that it cools and condenses enough to close the bottle off.

Once we get back to the lab we run the samples through a manometer (pressure-reading device) to compare the gas pressure in the bottles to the ambient room pressure. After that we stick it on a gas chromatograph and measure the bottle’s levels of air, water, CO2, and SO2. Fumaroles from different areas have different gas concentrations, and this helps us to understand the magma and gas beneath the crater’s surface.

Not a day goes by without me learning something incredibly interesting!





At The Edge Of Oblivion

3 09 2008

Today I did another amazing thing. I suppose if I keep calling everything I do amazing people won’t know how to distinguish daily stuff from special stuff. Either that or you’ll all become geologists! My evil plan will finally come to fruition!

Ok, in all seriousness I did something incredible. So you know the vent in Halema`uma`u I keep writing about? Today I helped install a time-lapse camera where the red dot in this photo is located. Keep in mind that the dot is about the size of 3 adults standing right next to each other, and make sure you click to see the full view of the image.

We also walked all along the rim on either side of that dot to perform maintenance on the ash-catching stations we have set up. I was directly over the vent and it was thrilling.

Here you can see the initial setup phase with the monster sulfur dioxide plume in the background. That’s the tripod.

Here’s the conversation I had with the geologist in that photo just seconds after I snapped the pic.

Him: “Hey, do you hear those loud banging noises from the vent?”
Me: “Yeah! They’re so loud! It’s amazing.”
Him: “If you hear a particularly loud one, get ready to run.”
Me: “Oh, right. Rocks can be ejected.”
Him: “You do realize that we could die, right?”
Me: “Yep!”
Him: “Ok, can you hand me those pliers over there?”

Not your average conversation at the office, was it? Let’s just say I pondered my time on this mortal coil for a minute whilst gazing into the swirling maw of Hell.

Maybe I should take up modelling hard hats? Anyway, here’s the end product of our efforts:

In the foreground you can see the solar panel that is responsible for powering the camera. The grey case on the ground is the battery, and the camera is in the open case on the tripod. The camera case lid is shut once we’re done adjusting it. The reason we installed it is that the vent has been growing. The lip and side walls have been collapsing quite a bit lately, so that first picture in this post actually shows the vent even smaller than it is now.

The noises issuing from the vent were otherworldly. I now understand perfectly why ancient Greeks and Romans believed that Hephaestus or Vulcan, respectively, was hammering away inside of the volcanoes. It honestly sounds like someone is forging things in the traditional hammer-and-anvil way. The booms are loud, metallic, and frequent. Sometimes it sounds like metallic popcorn, and other times it sounds like the resonating, drawn out intonation of a gong. It’s not always noisy like this. In fact, everyone is remarking on how unusual the noises actually are. I feel privileged to have heard them.

For those who are curious, I threw several rocks into the vent. I stopped after it belched out a massive plume that immediately blew in our direction. Making Pele, the Hawaiian volcano goddess, angry while perched on the lip of the vent was not on my To Do List for today.

Also of note: Both my photography and my person are present on the official HVO website! Visit the Kilauea Eruption Update page on HVO’s site to take a look. August 28th is the magic date. Those of you keeping up with the blog will recognize some of the images! The Quicktime video from August 31 is definitely worth a watch, too.