Volcanologists knew something was coming.
Between November 1957 and February 1959 measurements from newly installed sensitive tiltmeter bases around the summit indicated that the whole caldera region was tilting outward, apparently because magma was welling up from the mantle and accumulating in the reservoir several miles beneath the caldera.
Between August 14 and 19, 1959, a swarm of deep earthquakes was recorded on the seismographs at the Hawaiian Volcano Observatory. The earthquakes were located about 35-miles below the volcano.
By October, tilt surveys of the caldera, using the new water-tube tiltmeter network, indicated that the summit reservoir of Kīlauea was beginning to inflate with new magma. Scientists later concluded that magma began its upward journey during the August swarm.
Another series of earthquakes – shallow tiny events beneath the caldera – began in mid-September near Halema‘uma‘u Crater. By November 1, more than 1,000 tiny earthquakes were being recorded per day.
Scientists conducted another caldera tilt survey during the second week of November and discovered it was swelling at least three times faster than during the previous months. Magma was moving into the summit reservoir at a high rate.
During the afternoon of November 14, earthquakes beneath the caldera suddenly increased about tenfold in both number and intensity. For five hours, the entire Kīlauea summit region shook as seismic tremor signaled magma was forcing its way from the summit reservoir toward the surface.
An erupting fissure of small lava fountains broke through the south wall of Kīlauea Iki Crater at 8:08 p.m. In the first 24 hours, activity decreased and then eventually ceased at the outermost fissure vents. By nightfall on November 15, only a single vent on the west side of the fissure remained active.
Over the next five days, lava fountain heights fluctuated between about 650 and 980-feet, with a maximum fountain height of 1,247-feet.
A brand new cinder cone called Puʻupuaʻi (translates to “gushing hill”) was formed. As cinder and spatter rapidly accumulated to form Puʻupua‘i, slabs of congealed spatter occasionally broke loose and slid down the cone into the churning lava lake.
The 1959 summit eruption occurred in Kilauea Iki, a collapse crater adjacent to the main summit caldera of Kilauea. There were 17 eruptive ‘episodes’ (or phase) of the eruption which ranged in duration from 1 week to 1¾-hours..
On December 17, episode 15 produced lava fountains that were approximately 1,900-feet high, the highest recorded in Hawaii during the 20th century.
That’s about three times the size of the Washington Monument. That’s also 124 feet higher than the tallest building in the US now: One World Trade Center. (CNN)
Downwind from high lava fountains, forests suffered tremendous damage. Trees were stripped of leaves and branches – or completely buried – by falling cinder. You can now walk through this area of the National Park; it’s called ‘Devastation Trail.’
A few ōhi‘a trees, dead and bleached, poke up through the pumice and very gradually some ōhi‘a, ōhelo and ferns are beginning to recolonize the dead zone (unfortunately, some blackberry, too.)
Here is a video of the eruption (unfortunately, there is no sound, the sound of an eruption is as impressive as the visual):
The lava lake attained its greatest depth (414 feet) and volume (58 million cubic yards) at the end of the eighth phase on December 11, 1959. The eruption ended December 20, 1959.
When we were kids, living on Kāne‘ohe Bay on O‘ahu, whenever the eruption happened we’d go to the Big Island to see it, including the 1959 eruption of Kīlauea Iki.
