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!

Fun with Gravity!

1 08 2008

Last Friday I helped one of my colleagues with a gravity survey of Kilauea. He’s measuring the gravity in several specific pre-determined areas around the volcano to determine if there’s a correlation between gravity changes and eruptions. Pretty cool. Behold, the Graviton EG!

This is a self-levelling electronic gravimeter. There are only a few of these in the world, so we’re renting this one from the University of Wisconsin. Yeah, I have no idea why they have one and the US Government doesn’t. Hmm. What’s going on up there, Wisconsin?

One of our stops was next to Kilauea Iki, a collapse crater off of Kilauea’s main caldera. In 1959 it erupted and formed a spectacular lava fountain between 180-240 feet high. Now you can walk across the remnants of the fiery lava lake. You can see the trail in the middle of this picture.

Here’s a picture of my gravimetry-loving Italian colleague. This picture has all sorts of cool stuff going on. Not only is he displaying the coveted USGS orange shirt, he’s also standing next to the Graviton, a USGS benchmark, our beast of a work truck, and you can see the plume from Kilauea’s current eruption behind the truck. Pretty freakin’ sweet. Also, notice the fine footwear on display. Hah. The gravity benchmarks are all near the road, so no hiking required. We generally wear industrial work boots.

Oh yeah, did I mention that I was driving? Yep. It’s a scientific fact that the bigger the truck, the more fun it is to drive…especially when you go off-road.

We ended the day by the Hilina Pali trailhead. I think the views speak for themselves.

Talk about a great end to the day. This is why geology is so much better than everything else. Hehe.

Everything except for poking it with a stick.

24 07 2008

Tonight after normal work hours I was trained how to monitor the vent at Halema`uma`u. Ever since the caldera explosions earlier this year, HVO has had staff members watching the vent around the clock. The explosions have been at night, so it’s critical to have someone monitoring it constantly. However, monitoring an active vent isn’t as simple as sitting and staring at it.

There are several measurements geologists, seismologists, and geophysicists use to forecast eruptive activity and study an active volcano. Some of these measurable factors include earthquakes/seismicity, vent temperature, and tilt (deformation).

Seismicity and earthquakes help us see the frequency and characteristics of movement inside the earth. Some earthquakes are very shallow and originate within the volcano, oftentimes near the magma chamber. Other earthquakes are deep and come from the earth’s mantle, more than 70 kilometers (43.5 miles) below the surface. We’re concerned with the shallow ones, since they often occur in “swarms” before a volcanic eruption. Tonight I learned how to examine a seismograph and earthquake data to determine if significant eruption activity is happening.

We constantly monitor the temperature of the sulfur dioxide (SO2) gas that Halema`uma`u emits. Temperature spikes can indicate changes in vent activity, or just changes in the weather. You have to pay attention to see what is significant.

Another of the things that we monitor closely is called deformation. We use electronic tiltmeters that are semi-permanently or permanently located all around the island to measure changes in the slope of various locations. If the slope of an area increases steadily, it can indicate that the magma chamber is filling up. This can mean that an eruption is in the near future. It doesn’t always, however, so we have to make sure that we see a definite trend or we’ll be caught crying wolf. Here’s a really cool example of how volcanologists used tilt to track Kilauea’s past eruptions.

There’s more than this to monitoring, but it’s late and I have a field excursion tomorrow! It’s going to be very low-impact, since I’m still 2 days away from medical clearance to resume hardcore field work. I’m housesitting for another volcanologist now, and this one has eight cats. It’s quite a bit different than watching the two dogs at the other house! Word has gone around the office that I used to be a vet tech, so my pet-sitting skills are proving helpful to members of the staff who want their vacations.

Just so you don’t feel deprived, here’s a picture of the ocean entry plume from last week. Tomorrow will bring new and exciting pictures of Mauna Loa, Mauna Kea, Hualalai, and the Kona coast, provided the weather decides to cooperate. We’re catching the rain from a passing tropical storm, and it’s quite wet right now. Anyway, the plume awaits!

Hot enough for you?

19 07 2008

The ocean entry was spectacular on Tuesday. It’s the terminus of a series of lava tubes that issue from Pu`u O`o, a parasitic eruption site on Kilauea’s flank. The ocean entry had dried up completely for a while after the lava fountain from one of my earlier posts began, but it’s back and better than ever. Instead of just oozing into the ocean or producing small explosions, the lava was shooting between 40-50 feet in the air. I saw 3 flashes of lightning in the plume while I was there. That’s a newly observed phenomenon that had just started the day. Like I said, spectacular. I’ll just shut up and let you see for yourself.

It was after 7PM when I arrived, but a full moon illuminated the plume and water quite a bit.

The plume was creating massive disturbances in the surrounding atmosphere. You can see a waterspout to the left of the plume. Genuinely amazing.

In that one the lava was reaching for the ocean as well as for the land. The entire time I was there the eruption was building a spatter rampart (a wall-like structure of ejected lava). Remember, the lava is 40-50 feet high in these photos.

So yes, all of you who were waiting on tenterhooks for actual lava…there you have it! I’ve never heard a group of entirely disparate people, young and old, all ooh and ahh like I did on Tuesday. Adults failed to disguise the outright wonder in their voices, and children decided to inform everyone else that this was much, much better than fireworks. I could’ve watched it forever. The earth doesn’t get any newer than this…or more beautiful.

Quick Plumage

14 07 2008

Kilauea painted quite a lovely picture last night, and even though I haven’t looked at my `Ainapo Trail pics I thought that you might enjoy these. They were taken slightly before midnight last night. The moon was nearly full and the stars were out en masse.

I told you it glowed at night.

And a slightly closer view:

That glow is intense.

I want to say thank you to everyone who has visited and/or commented. The incredibly positive response this site has garnered from family, friends, colleagues, and complete strangers is my motivation to continue publicly documenting my ongoing adventures in volcanology. I can’t believe it hasn’t even been three weeks yet!

`Ainapo Trail pics and story will appear tomorrow, I promise.

Oh, I should also mention that Okmok volcano in Alaska erupted today. The Alaska Volcano Observatory site has some interesting information about the eruption. One of their scientists has been here at HVO for a few weeks, and he was supposed to be on seismic watch at AVO today. The poor guy missed out! I’m crossing my fingers that we’ll have some explosive activity while I’m over here. It’s every volcanologist’s dream.