A couple of years ago I was blessed to witness one of our planet’s most spectacular phenomena: an erupting volcano. Kilauea on Hawaii’s Big Island has been in near constant eruption for centuries (millennia?), slowly elevating Hawaii’s slopes and expanding its shoreline with lava that cools and hardens to form the newest rock on Earth. This island building process has been ongoing for the last five-million or so years, as the Pacific Plate slowly slides northwest over a hot spot in Earth’s mantle, building the northwest/southeast-trending Hawaiian chain of islands. The Hawaiian Islands get successively older moving northwest up the chain, with the island of Hawaii currently on the hot-seat, making it the youngest of the chain’s exposed islands (though there is a newer, still submerged island rising south of Hawaii).
As active as Kilauea is, much of its volcanic activity occurs out of the view of the average visitor. But on my annual visit in September of 2016, my workshop group and I got a firsthand look at Kilauea’s island-building furnace when the lava lake inside Halemaumau Crater rose high enough to be seen from the safety of the caldera’s rim. (Read more about this experience in my 2016 blog post, Nature’s Transcendent Moments.)
This week Kilauea is back in the news with an eruption far more significant (and destructive) than the event I captured in this 2016 image. The 2016 experience resulted from the good fortune of catching an elevated phase of the normal summit crater activity that started in 2008. The Kilauea activity that started this week, complete with earthquakes and lava flows, is a new eruption in Kilauea’s east rift zone. It could be over in hours or days, or could continue for decades.
The relatively fluid nature of Hawaiian lava makes its eruptions less “run for your life!” crises and more, “Well, I guess I better start packing up,” events that range from inconvenience to financial disasters, but are rarely life threatening. Local residents know the risk and are generally philosophical and positive when Pele points her fiery finger in their direction.
On the other hand, a volcanic eruption in the Cascade mountains of the Pacific Northwest is potentially far more dangerous than a typical Hawaiian eruption. We only need to look back on the eruption of Mount St. Helens in 1980, a relatively minor event on the continuum of possible Cascade eruptions, to see the extreme power of an explosive eruption. The viscous lava of the Cascade volcanoes makes their eruptions far more dangerous than Hawaii’s eruptions. While Hawaii’s basalt lava flows easily when internal forces push it to the surface, the Cascade lava resists, setting up an irresistible force versus immovable object standoff that is resolved suddenly and explosively (in favor of the irresistible force) as a cataclysmic explosion.
The undeniable aesthetic appeal of the Cascades is actually a byproduct of the the viscous lava that makes them so explosive. As it emerges and flows down the mountain’s side, Cascade lava doesn’t spread too far before cooling in place. The result is a strato-volcano that builds more vertically to form the towering symmetrical cone that photographers love to photograph. The more fluid Hawaiian basalt spreads rather than builds, wreaking slow-motion havoc on the countryside and accumulating over thousands of years to form massive, but visually unimpressive, flat, shield volcanoes.
Having just returned from a couple of weeks photographing in the Pacific Northwest, the beauty of the Cascade volcanoes is fresh in my mind. But nothing compares to witnessing the actual mountain making process in action.