June 25, 2009
A weekly feature provided by scientists at the Hawaiian Volcano Observatory.
The beginning of a new era—Kilauea's 1952 summit eruption
The HVO Web site was recently revamped to make access to our increasing number of Webcams easier for About 20 minutes before midnight on June 27, 1952, almost exactly 57 years ago, Mrs. John Fox walked from the living room of her home on the east rim of Kilauea caldera into an adjoining room. She was instantly startled by a loud, whistling roar coming through an open window. Running back into her living room, she saw a bright orange glow lighting the night sky.
At about the same time, just down the road at Kilauea Military Camp (KMC), Colonel B.W. Rushton pointed out the bright glow to Hawaiian Volcano Observatory (HVO) staff member John Forbes, who quickly called Gordon Macdonald, then Scientist-in-Charge of HVO.
When John Forbes arrived minutes later at HVO, on the edge of Kilauea caldera, he was greeted by the top of a huge lava fountain rising above the rim of Halema`uma`u. The crater was then nearly 245 m (800 ft) deep—more than twice its current depth from the rim to the crater's floor. By the time Gordon Macdonald arrived at HVO some 10 minutes later, the fountain was no longer visible, but incandescent fragments could still be seen arcing out of the crater.
Quickly grabbing the necessary equipment, Macdonald and Forbes set out by car for Halema`uma`u Crater to make detailed observations. As they followed Crater Rim Drive down onto the western floor of Kilauea caldera—the section of road that is closed today due to ongoing summit activity—they encountered a choking, sulfurous fume cloud so thick that they could barely see the road.
The fall of tephra onto the road was so heavy that they were hard-pressed to keep the car moving forward as it plowed through the drifts of pumice. The hail of tephra onto the car, with pieces reaching up to 10 cm (4 inches) across, sand-blasted the car's exterior to the point that it later had to be repainted and have its windshield replaced.
Pressing onward, Macdonald and Forbes passed through the tephra fall and quickly walked to the southeast rim of Halema`uma`u, reaching it about 10 minutes past midnight. When they peered into the crater, they saw a continuous line of lava fountains, 790 m (2,600 ft) in length, crossing the entire crater floor from southwest to northeast and extending part-way up the northeastern crater wall.
For the most part, the individual fountains were 15 to 30 m (50 to 100 ft) in height, but a fountain 120 m (400 ft) high jetted up near the bottom of the southwestern wall of the crater—probably a diminished version of the same fountain, at more than 245 m (800 ft) in height, seen minutes earlier from HVO.
Though views were poor due to the heavy fume, brief glimpses of the crater floor showed that older spatter cones on the floor of Halema`uma`u had already been buried beneath a rising lava lake. This suggested that more than 3 million cubic meters (4 million cubic yards) of lava were erupted in the first half-hour of the eruption. It would take about six days for Kilauea's current east rift zone eruption to pump out that much lava today.
The eruption rate quickly declined after the initial outbreak, but lava fountains continued to play on the surface of the lava lake over the following weeks. By late summer 1952, activity had begun to decline, but the eruption persisted until November 10, when the last fountaining activity was observed.
Having erupted for 136 days, the 1952 summit eruption brought to an end, in grand fashion, any doubts as to whether or not Kilauea was still alive. Prior to 1952, Kilauea had been quiescent since October 1934, when the previous summit eruption had ended, and some had begun to think that Kilauea was dead. But frequent earthquakes and the occasional swelling and shrinking of the volcano over the intervening years told volcanologists otherwise. It was no great surprise, then, when the eruption finally occurred.
Followed by dozens of eruptions in the years since, the 1952 eruption undoubtedly ushered in the current era of volcanic activity at Kilauea. Today's ongoing summit and east rift zone eruptions are just the most recent in the string of eruptions that have followed since Mrs. Fox was surprised by the glow outside her living room window.
Kīlauea Activity Update
Surface flows in the Royal Gardens subdivision may have stagnated early this past week in response to a deflation-inflation (DI) event at Kīlauea's summit. Smoke continues to rise, however, from forested kipuka in the subdivision, indicating that at least some burning continues. At the coast, the Waikupanaha and Kupapa`u ocean entries remain active and continue to produce prominent plumes, accompanied by small littoral explosions, as lava spills into the ocean.
At Kīlauea's summit, the vent within Halema`uma`u Crater is still emitting elevated amounts of volcanic gas, resulting in high concentrations of sulfur dioxide downwind. Glow from the vent was visible at night through the past week, and rare views into the vent by HVO scientists found that the lava surface is still present about 205 m (675 feet) below the floor of Halema`uma`u Crater.
No earthquakes beneath Hawai`i Island were reported felt this past week.
Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov. Volcano Watch is a weekly article and activity update written by scientists at the U.S. Geological Survey's Hawaiian Volcano Observatory.
Updated: June 29, 2009 (pnf)