Liquid Rock

  Volcano, Hawaii, United States
Monday, March 16, 2009

We are fascinated by lava, and ever since we found out we were moving to the Big Island we have been determined to see orange, molten lava flowing on the surface.  At this stage of Kilauea's ongoing eruption, this turns out to be easier said than done.  While historically there have been very dramatic displays of lava shooting into the air and flowing down slope, currently Pele (the Hawaiian volcano goddess) is being somewhat secretive and lava is mostly flowing underground.  We spent a lot of time poring over maps of the active lava zone, talking to park and county rangers, and monitoring the daily update on volcano activity (http://volcano.wr.usgs.gov/kilaueastatus.php) to determine if there were any areas of surface flow, and if there were, whether it was at all safe to see it.  At the end of last week scientific updates indicated there was in fact a "strong surface temperature anomaly" indicating lava on the surface plains just above where lava has been flowing into the ocean. We decided to give it a shot, not at all convinced we would actually see liquid rock.

We got up at 4:00 Sunday morning in order to start the long hike at sunrise.  We had with us 2 gallons of water, lunch, dinner, snacks, and the rest of the usual gear.  The plan was to hike about six miles over recent lava flows (less than 20 years old) toward the obvious ocean entry (giant steam plume billowing high into the sky), without the aid of a trail.  We expected a difficult scramble of a hike, since lava is notoriously challenging to walk on. There are two main classifications of lava: pahoehoe, which is relatively smooth and formed by slow flows, and a'a, composed of loose razor sharp rocks and formed by faster flows.  The way to remember these names is to think of the sound you would make while walking over the rough version in bare feet ("Aa!  Aa!").  We were pleasantly surprised to find very little a'a.  

Trippy moonscape

Fresh lava fields are desolate places.  The only vegetation is the occasional fern sheltering in a crack where there is somehow enough water and nutrients to support life.  There is no shade.  There is no water.  There is very little flat surface.  There is only rock.  Yet these landscapes are strangely compelling.  We were continually awed by the beauty of the lava-up close there is infinite variety in shapes, textures, patterns, formations, colors, and even the sounds as you walk.  Every footstep was completely different than the one before it, even though from far away it looked like miles and miles of featureless black moonscape.  

Lunch spot

After hiking for four miles we sat for a bit to eat lunch and take stock.  We were very close to the active flow, evident from the steam vents that dotted the landscape in front of us.  Helicopters had been touring between Pu'u O'o (out of site) and the ocean entry.  As we got closer we noticed that many of the helicopters spent time just upslope from the ocean entry, hovering over the plain we were walking across.  We took this as a strong indication that the surface flow was still active, and a clue to where the action was.  We took a compass bearing on the general area the helicopters were targeting and set out. 

Shortly after leaving our lunch spot the rocks became noticeably warmer, the radiant heat reflecting off our arms.  As we kept going the rocks got warmer and steam vents more common.  The smell of sulfur became stronger.  Intense heat waves rising off the rocks in front of us distorted views to the horizon.  The texture of the lava was noticeably different than in the older flow with a silvery sheen that was very fragile to the touch (or footstep).  In this area, lava flows through tubes beneath the surface on its way to the ocean, so we knew there was lava under our feet; now if we could just find it on the surface...

Navigating this landscape had some obvious challenges-clearly we were on an active flow, even if we couldn't see any orange and weren't yet to the spot being keyed on by the helicopters.  Each footstep had to be gently tested before full weight was applied, and we tried to stay on the high spots.  We frequently had to check the bottom of our boots to make sure they weren't getting too hot (they never did, even when the rocks were almost too hot to touch with our hands).  We were quite close to the ocean entry now, by far the most active lava spot on the island. 

Suddenly Dan saw a small pool of light silvery liquid rock, with brilliant orange edges.  This was it, what we had hiked so many miles to see.  As we watched, it burbled and slowly spilled over the edges of the small depression from which it emerged.  We were in awe watching this pool expand by tiny orange rivers on one side, and thick drops on the other.  We saw the flow get slowed by some unseen obstacle, and "ropes" of pahoehoe form.  So many of the bizarre formations we had seen and wondered at were being created right before our eyes-this was truly an experience of a lifetime.  Naturally, Dan threw some rocks in the pool (how could you not?), expecting them to sink or create ripples as they would on a pond of water, but we were shocked to see them bounce off instead, even as the flow continued to move.  What had been liquid only seconds before was already semi-solid.  The flow was so slow and gentle, but at the same time so fast when you considered it was oozing a new foot-deep rock layer from the center of the earth in a matter of minutes.  As it slowly grew and oozed closer to us (still 30 feet away) we could hear it making a distinct crackling sound, much like a campfire.  We stayed as long as we could, and when the flow edged a bit closer and we could feel the radiant heat on our faces, we decided it was time to give Pele her space.  

Lava pool

Crazy?  Maybe.  But it was one of the most fascinating and awe-inspiring things we've ever seen.  What we saw was new solid earth being created, the shape of the land changing...nothing short of the birth of the Hawaiian Islands right before our eyes.