It's 2019 for many around the world! At the time of this writing, the Pacific Northwest is still living in the past. So let's look back on some of the notable themes of 2018, and at the end, you'll get a sneak peek at what's coming up for Rosetta Stones in the new year.
Of course, Kilauea was the biggest news of all! The feisty Hawaiian volcano moved eruptive operations to Leilani Estates and surrounding areas, eating a fair number of subdivisions and providing some really spectacular action before going completely quiet. Will Pele renew her efforts in 2019? It's a distinct possibility! Kilauea is young and restless, and I won't be surprised to see hot new eruption action before the end of the decade.
Things got incredibly exciting in Hawaii over the last week. Kilauea's East Rift Zone showed an abrupt uptick in seismic activity on Monday afternoon, showing that magma was on the move. No one knew if it would actually erupt; magma often goes traveling without showing up on the surface, and this was in an area that hadn't seen activity in the past. But everyone was on high alert – especially when cracks began to appear in one of the Big Island's newest subdivisions.
Things remain pretty heated in Hawaii. The Leilani Estates eruption continues apace, at least thirty-five homes have been destroyed, and there's no sign the lava will stop any time soon. What comes next, no one knows for sure; but judging from the ongoing seismic activity in the area, and the continued opening of new fissures, it looks like the eruption certainly won't be ending this week.
Volcanoes typically give warning before they erupt, but that warning may only be hours. You could be left with little or no time to prepare. May is Volcano Awareness Month in Washington State, and with the Kilauea eruption in Leilani Estates causing more evacuations, now is an excellent time for us all to find out if we're living in or visiting volcano country. If so, it's time to prepare.
Kilauea's most recent lava flows reached the sea over the weekend, and they've been beach bumming ever since. Few things are as dramatic as molten rock contending with seawater. We'll be talking about all the neato things that are happening and that we may see if the eruption continues. We're starting with LAZE, which in this case isn't something you do on a hot summer afternoon.
The eruption on Kilauea volcano has settled into a routine, with one fissure pumping lava in a fiery river that runs to the sea, creating new land. It's a pattern that has repeated on the Hawaiian islands for millions of years. Unfortunately, there's another pattern repeating: people seeing a rather calm and perfectly ordinary volcano doing what shield volcanoes do, and thinking the entire island's about to blow. An eye-rolling number of doomsday predictions have been made since the eruption shifted to the Leilani Estates/Vacationland area.
You know what's better than a fireworks show? A dust devil made of lava. You've got to put down whatever you're doing and watch this, because it is spectacular...
For a while, there, Kilauea settled into a predictable routine, and there wasn't much news surrounding the eruption. The most exciting and terrible thing was the lava channel developing a kink and the flow covering more structures and a park; otherwise, you could pretty much depend on the news being pretty much the same every day. But this past week has seen one quite dramatic event, plus a couple of awesome ones if you're a volcano geek.
First, the dramatic (and for some, traumatic) event: on July 16th, a lava tour boat skirted a little too near to the active ocean entry and got to see a littoral explosion up far too close.
Kilauea's been almost as quiet as this blog for the past few weeks! Summit collapses have paused, earthquakes are down to just the occasional rumble, and SO2 emissions are the lowest they've been since 2007. Most notably, the spectacular Fissure 8 has gone completely still. All that remains of the robust lava river is a small crusting pond deep within the snazzy new spatter cone.
Has Pele ceased her remodeling, or is she just taking a nice break before continuing? We won't know for a few months at least – pauses in eruptive activity are common on active volcanoes, and they can last quite a while. All we can do is wait and watch.
In the meantime, let's take a look back at the brief life of Fissure 8. It's a really wonderful example of how Hawaiian volcanism works, and we got to watch it all from birth to (possible) death.
We left Fissure 8 busily devouring Vacationland and Kapoho Bay. By the next day, June 7th, the lava flow pumped out by those industrious fountains had built a delta 1.2 miles wide. That was just the visible flow: the water upwelling around 1,000 seaward of the new shoreline suggested part of the flow front was happily tooling along on the seabed quite a ways out.
Kilauea's been quiet since August, but here's the thing about volcanic eruptions: the science doesn't end when the lava stops flowing. While it's going on, events are happening too fast to process on more than a superficial level. The amounts of data being generated are staggering. Volcanologists are scrambling to merely collect it, and as far as interpreting it, most of the in-depth stuff has to wait until the volcano goes sleepy-bye. The eruption generally doesn't give anyone a chance to do more than the most superficial analysis when it's sudden and constantly involving.
Other Major Geologic Events
There were more geologic happenings around the world than I had time to write up, but a couple of them made some particular waves. Sometimes literally.
Last Friday, an unusual sequence of events unfolded on Sulawesi Island in Indonesia, with catastrophic results.
It began with an earthquake. This wasn't at all out of the ordinary: Indonesia is a nation of islands born from very complex and deadly plate tectonics. Sulawesi is right in the path of a triple junction, where three major plates – the Australian, Philippine, and Sunda – converge. The island is stitched together from island arcs and continental fragments mashed together by colliding plates, plus volcanoes birthed by subduction. The area is a mess of thrust and strike-slip faults all trying to accommodate the motions of the major plates, plus microplates resulting from all the tectonic chaos.
On Friday morning, Anchorage got a jarring reminder of the importance of seismic building codes.
Alaska's no stranger to earthquakes. The Pacific plate is headed northwest, but that oceanic slab is too heavy to override the more continental North American plate. But those 2.28 inches (57mm) of plate per year need to go somewhere, so the slab dives. Tectonic forces we're still working to fully understand pull it down into the mantle. And as it goes, of course, earthquakes and volcanoes happen.
The M 7.0 earthquake that struck Anchorage occurred in that slab, 27 miles (44 km) down. The rupture happened a mere 8 miles (12km) from the city. The large size of the earthquake, plus its proximity, meant that Anchorage and its surrounding areas saw some pretty heavy-duty shaking.
We spent some time with rocks that burn, and with rocks that preserved evidence of ancient forest fires. In the process, we discovered charcoal that won't light your grill, but will gouge your rock hammer!
We all know charcoal, right? Most of us have taken bits of it from the ashes of wood fires and played with it. It's light, soft, and crumbly. It leaves a black sooty residue on everything it touches. It's marvelous stuff for drawing, even though it's prone to unintentional smudging. You can easily crush it to powder. Take a moment to imagine it. Score it with a fingernail. Remember how soft and delicate it is.
Now imagine taking a chunk of it from the ground, and seeing it blacken your fingers, but it's heavy.
Were you naughty (or lucky) enough to get some coal in your stocking this Christmas? Congratulations! Coal is a fascinating rock and tells us a lot about the geology of ages past in the locations where it's found.
You probably wouldn't expect Santa to be able to locally source his coal – after all, it's a rock that requires swampy or marshy areas with lots of lush plants. That's not really what you find around the North Pole! But a mere 650 miles away, halfway to Norway, you'll find an island that provides all the coal Santa would ever need. It's the glacier-capped island of Svalbard, and Santa wouldn't even have had to go digging when he first went looking for coal. It was right in plain sight...
We looked back at previous pioneers, and met a new one.
It's International Women's Day. While we're appreciating living women worldwide, let's celebrate some of the pioneering women who made the current state of earth science knowledge possible.
Dr. Janet Vida Watson's geology career is a love story.
She loved her rocks immensely. To her, they weren't inert, cold stone. They had character. They had emotions. She loved her "happy rocks," and trusted them more than she trusted the isotopes labs wrested from them (though she never shied away from new technology: on the contrary, she eagerly embraced it). She turned to them throughout her career, and they imparted their life stories to her, sometimes revolutionizing an aspect of earth science in the process.
She loved geology so much she did it on her honeymoon, with her groom, John Sutton. She adored field work, and teaching students to do this good science of rock-breaking. She loved it to the end of her life.
And, finally, we explored the Galápagos with Charles Darwin, and discovered that it's not just finches evolving on those islands!
Darwin, the Galápagos and the Evolution of Basalt
The Galapagos, a fairly young and still quite active group of volcanic islands, are an ideal playground for a keen young geologist. The hot, dry climate, combined with lava flows that erupted quite recently in geologic terms, presents a sparsely-vegetated and quite lightly eroded rock record. For a lover of the good science of rock-breaking such as Darwin, it was enthralling. He scrambled over several of the islands, taking notes and rock samples and puzzling over the origins of what he saw. Less than ten years after the voyage of the Beagle concluded, he published his findings on the Galapagos and other islands in Geological Observations on the Volcanic Islands, visited during the Voyage of the H.M.S. Beagle.
Now, keep in mind that Charles Lyell, the father of modern geology, had published the last volume of his Principles of Geology barely a decade before. Western scientists were only just beginning to grapple with the great age of the earth. When Darwin began his travels, James Hutton and other Plutonists had only just convinced most of the scientific world that basalt was deposited by volcanoes, not laid down by seawater. And the science of volcanology hadn't really been born yet when Darwin first laid eyes upon the Galapagos. Yet he saw things no one had eyes to see.
We covered a lot of very new ground in 2018. In 2019, we're going to take a look at another, even more unusual Indonesian tsunami, get into the geology of birthstones, and cover the basics of basalt. And I'm sure the planet will throw a lot more geologic excitement our way!
Happy New Year, my dear readers! May this be your best year yet.