The original burning ring of fire.

13 08 2008

Today was utterly amazing. I went with one of HVO’s Kilauea research geologists to the active lava flow field to map the new surface flows, perform a hazard assessment, and collect a sample. After we made the hour drive to the flow field we hiked across some of the miles of lava flows near the lava’s ocean entry. We were greeted with this:

That’s a skylight, which is essentially a hole with a view into a lava tube. Here’s a close up.

It’s hard to discern in this picture, but there was a veritable river of lava rushing past. The bright orange at the center is, in fact, lava. The area surrounding the tube is all flow that has issued within the last day or so.

That wasn’t enough lava for us, however. We continued hiking across the flow field until we found an active surface flow. That’s when things turned violent…for the lava, that is.

Hey, I had to attack it with a hammer before it attacked me, right? In actuality, this is how we collect samples from slow-moving surface flows. After you use the rock hammer to grab some lava, you toss it in a bucket with some water to quench it and make it safe to handle.

That picture is unfortunately a bit blurry, but it demonstrates the elasticity of the molten lava. The lava that I’m up close and personal with in these pictures is approximately 1000 degrees Celsius. That translates to 1832 degrees Fahrenheit for those of us from the United States. The extreme heat radiating from the flow is the reason I’m wearing those silver gloves and the stylish balaclava. I have my hand up to my eyes to shield them from the heat as well. It was like nothing I’ve ever felt before. Every atom of my body was enveloped by the invisible heat waves from that molten rock. Incredible.

This shot gives a better perspective of the shapes a pahoehoe flow can take.

I decided that the lava was ready for its close up.

After the necessary sample was safely quenched and packed away for later analysis, we hiked back across the flow field in order to map the newest surface flow with potential to threaten people. We used GPS to map it, and then headed into the forested kipuka. I probably ought to mention that the lava had was flowing through the kipuka and burning the forest.

The lava was setting fire to everything in its reach, and the flames were travelling up downed tree branches and grasses. Small methane explosions were nearly constant, so we couldn’t get too close to the kipuka flows. This begs the question of what to do when you encounter a lava flow that is in the process of burning a forest. Well, I am happy to report that I have the answer.

Why, you poke it with a stick of course! Nothing teaches unruly lava to behave quite like jabbing it with a stick.

I think it’s safe to say that this was one of the greatest days of my life.

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Highly educational

28 07 2008

After last week’s intense office work, I was dying to get back in the field. Since my knee wasn’t cleared until Saturday, my field experiences would have to be tame. Still, that doesn’t mean they were boring! Since there are a good number of pictures, I’m going to break things up into Thursday and Friday. Tonight’s post will cover last Thursday.

My boss organized a field trip for anyone interested to Kona’s Gold Coast. 13 of us set out from HVO early Thursday to begin a day of learning in the best way possible – while standing in front of the subjects of our study! The first stop was Rainbow Falls outside of Hilo.

While the average tourist might have stopped here to marvel at the falls themselves (and the tiny rainbow you can just glimpse at their base), we were here to look at the volcanic stratigraphy. Behind the mist of the falls it’s possible to glimpse columnar basalt. Lava flows of several different ages are visible here.

The next stop was at Kaumana Cave, a well-known skylight in a massive lava tube created by the 1881 eruption of Mauna Loa. The tube is about 25 miles long, and definitely illustrates the hazards posed by lava flows. The guy at the bottom of the picture is a visiting scientist from Japan, and the guy on top of the tube is one of our preeminent seismologists.

While stopped at a kipuka for some geologic question and answer time, I spotted this plant that was reveling in the morning dew. Just thought you might like some Hawaiian foliage to brighten your day! If any of you biologically-inclined sorts know what kind of plant this is, do tell.

This is an incredibly interesting thing to geologists. It’s called a xenolith, which translates from Latin as “foreign rock.” That’s exactly what it is. This particular xenolith is dunite, a rock that is composed of coarse grains of olivine and originates in the earth’s crust. Essentially, the basalt grabbed the piece of dunite from where it formed deep below the surface and carried it upward, where it came to rest inside the flow. This particular lava flow is one of the best sources of xenoliths in the entire world. It is from Hualalai volcano, and the eruption took place in 1800. There were plenty of other xenoliths nearby ranging from clinopyroxene to gabbro and more. This is amazingly interesting for someone who is captivated by crust-eruption interactions (yeah, that would be me).

Our trip informed us in detail about Kilauea, Mauna Loa, Mauna Kea, and Hualalai. The only volcano we didn’t touch on was Kohala, the oldest one on the island. My boss is so knowledgeable on all things Hawai`i that it blows my mind. I know he was born and raised on the islands, and that he’s been working at HVO for over 20 years…but still! He’s brilliant. Here is where I ought to mention that he’s the scientist who proved that Kilauea volcano has a deep plumbing system. This is critical to our understanding of the volcano’s eruptions. This is such an amazing opportunity.

After our long day of learning, we headed down to Mauna Loa’s 1881 lava flow on the western portion of the island. The flow took 8 days to reach the coast, and reach the coast it did. It travelled over 31 miles, and this is how it looks today.

Not too shabby, is it? The grass is a pretty nasty invasive species and is resistant to fire. Eradicating it is nearly impossible, but at least it makes the pictures look good. We ended the educational portion of our trip at Anaehoomalu Bay (known as A Bay by people who don’t want to attempt THAT tongue-twister). You can just look at the water and guess what we did when we got there. I’m not going to give away all of our secrets.

Tomorrow will be pictures and talk about Friday’s gravity survey. This Thursday I’m going to the southern end of the island to collect samples from littoral cone deposits on Mauna Loa’s Southwest Rift Zone. I’m ready and waiting for the fieldwork to begin anew!





`Ainapo Adventures

15 07 2008

At long last, the `Ainapo Trail story in pictures and words! Huzzah, and here we go.

The day started early and 5 of us headed up Mauna Loa’s northwest flank in my boss’ heavy duty truck.

Once we were near the summit, the helicopter met us and flew us across the caldera to the southeastern flank. My boss was already waiting for us, as the helicopter had taken him up first. We split into teams of 3 to perform our surveys. My group headed down the `Ainapo Trail, certain to camp overnight. The second group headed around Mokuaweoweo (Mauna Loa’s caldera) and was able to drive back down the same day.

Here’s the start of our survey. We were at the 3rd benchmark here, and we were just finishing up lunch. The day started off beautifully.

The good weather was not to remain our companion for long, however. This was the scene near our 5th or 6th benchmark. I have to say that I love my boss’ outfit. Like all good geologists, his style is impeccable. You’ve seen the way I dress in the field, so be aware that this is utterly tongue-in-cheek. Perhaps we should look into Nike sponsorship or something. At least then we’d match.

The fog was accompanied by rain, and we found our last benchmark of the day in a steady drizzle. Luckily for us, the bossman is resourceful and found a dry (albeit cramped) place to sleep for the night. In a lava tube. On the side of the world’s largest volcano. This has to be one of the highlights of my outdoor life, if not of my entire life.

My boss did a lovely job of modelling the tube for the camera. We had a simple dinner of minestrone heated over the tiny stove, and then we were about ready for sleep. Camping conversations are always fun, and ours was no exception. I’m not going to post a photo of my portion of the lava tube, as it was an even tighter fit than the one pictured. My parents do not need their respective blood pressures elevated any higher than necessary by my escapades.

I do have to say that one of the most rewarding parts of camping is the unexpected splendor of the early morning views that are often available. When you reach a campsite at night, the daylight can offer wonderful surprises. Shortly after dawn on Mauna Loa was no exception.

The plume from Kilauea’s Halema`uma`u vent is visible in the middle of the picture. It is situated at approximately 4,000 feet above sea level. Our campsite was about 9,000 feet above sea level. We started our hike around 13,000 feet above sea level. The temperature dropped to 42 degrees Farenheit in our lava tube, so we weren’t that uncomfortable. I slept poorly, but that could have been because my tube section was the size of a coffin. Most of the hike was over a`a lava, and that’s why I was so battered by the end.

The survey went well overall, and we’ll polish the data tomorrow. We should be able to compare this information with last year’s in order to assess Mauna Loa’s deformation rate. This, in turn, will enable us to form a better picture of the volcanic activity beneath the mountain’s massive surface.





Day of exploration.

29 06 2008

Yesteday was gorgeous on the island. I did some necessary grocery shopping in Hilo and then headed to Chain of Craters Road to explore the park a bit. I’m living at the USGS dorm while I’m here, so that was my post-grocery starting point.

Dorm, sweet dorm.

Chain of Craters Road runs through lava field of varying ages. The lava is often cracked and deformed. This is a Pahoehoe lava flow that has fractured.

Pahoehoe fracture

As I continued to the end of Chain of Craters, I came across something ominous:

An effective deterrent.

If that’s the road sign, then where’s the road? Oh, right.

4WD only, right?

At any rate, I decided to get a closer look at all of this lava. It’s actually very interesting up close.

Who knew?

The small holes in the lava are called vesicles, which makes this a vesicular basalt. The more large vesicles present, the slower the lava cooled. Rapidly-cooled lava won’t have vesicles. The vesicles are formed by gas escaping from the molten lava. This one is my favorite.

Mmm.

From the end of Chain of Craters I was south of the current eruption’s ocean entry point. I’ll go around closer soon, but for now here’s the sulfur dioxide plume caused by the lava’s contact with water.

Fire and water.

Finally, I headed back towards the dorm. On the way back I stopped at Thurston Lava Tube. These are cave-like structures formed when lava moves beneath the surface of a flow. When they’re extinct, they look like this:

Freaky when you\'re alone.

I went up to HVO last night around midnight to see the glow from Halema`uma`u’s vent. It faded in and out due to the shifting of the wind, but it’s still enthralling to watch glowing from the earth’s depths. Today is a day for relaxing, as tomorrow I leave at 6AM to drive to Mauna Loa’s summit for my first day of field work. Wish me luck!