“Astonishment and awe for some moments rendered us mute, and like statues, we stood fixed to the spot, with our eyes riveted on the abyss below. Immediately before us yawned an immense gulf, in the form of a crescent, about two miles in length, from north-east to south-west, nearly a mile in width, and apparently eight-hundred feet deep.”
“The bottom was covered with lava, and the south-west and northern parts of it were one vast flood of burning matter, in a state of terrific ebullition, rolling to and fro its ‘fiery surge’ and flaming billows.” (Ellis, 1823)
In 1823, Reverend William Ellis visited Kīlauea caldera on his journey around the island of Hawaiʻi. He was the first foreigner to be shown the home of Pele.
By the time Ellis arrived, more than 300-years after the summit collapses of the late 1400s, the caldera had begun to refill. He measured the chasm from the highest rim to its depths; it was over 1,000-feet deep, with a series of terraces that stepped down to a vast inner crater that occupied nearly half the caldera’s floor. (NPS)
“Sometimes I have seen what is called Halemaʻumaʻu, or South Lake, enlarged to a circuit of three miles, and raging as if filled with infernal demons”. (Halemaʻumaʻu is lit., fern house.)
“On another occasion I found the great South Lake filled to the brim, and pouring out in two deep and broad canals at nearly opposite points of the lake.”
“The lava followed these crescent fissures of fifty or more feet deep and wide until they came within half a mile of meeting under the northern wall of the crater, thus nearly enclosing an area of about two miles in length and a mile and a half in breadth.”
According to Hawaiian oral tradition, the Kīlauea caldera formed during an epic battle between Pele, the Hawaiian volcano deity, and her younger sister, Hiʻiakaikapoliopele (Hiʻiaka.)
Pele had sent Hiʻiaka to fetch her lover, Lohiʻau, from Kauai. Upon returning, Hiʻiaka discovered that Kawahine‘aihonua (Pele, the woman who eats the land) had broken her promise and set fire to Hiʻiaka’s beloved ‘ʻōhiʻa forests.
To avenge this transgression, Hiʻiaka made love to Lohiʻau at the summit of the volcano, in full view of her sister. Pele lashed out in anger and buried Lohiʻau beneath a flood of lava.
Driven by remorse, Hiʻiaka dug furiously to recover the body. Rocks flew as she dug the great pit. Their brother stopped Hiʻiaka from digging deeper, for doing so would surely have let in water and put out the fires of Pele. Thus the great caldera of Kīlauea was formed. (NPS)
Within the heart of Kīlauea, a great reservoir swells with magma prior to an eruption. In the late 1400s, however, large volumes of magma erupted or moved elsewhere in the volcano, emptying the magma reservoir.
Its internal support withdrawn, the top of the mountain collapsed, accompanied by explosive eruptions. Great blocks of the old summit slumped inward. The gaping depression that formed was ringed with stepped terraces descending to its floor. (NPS)
The summit caldera (‘crater’) of Kilauea is 2-1/2 miles long and 2 miles wide and its floor has an area of approximately 2,600-acres. Near its southwestern edge the caldera floor is indented by the depression Halemaʻumaʻu, the ‘Fire Pit,’ a collapsed crater about 3,200-feet wide. (NPS)
Geologic evidence suggests that the modern caldera of Kīlauea formed shortly before 1500 AD. Repeated small collapses may have affected parts of the caldera floor, possibly as late as 1790. For over 300-400 years, the caldera was below the water table.
Kīlauea is an explosive volcano; several phreatic eruptions have occurred in the past 1,200 years. (Phreatic eruptions, also called phreatic explosions, occur when magma heats ground or surface water.)
The extreme temperature of the magma (from 932 to 2,138 °F) causes near-instantaneous evaporation to steam, resulting in an explosion of steam, water, ash and rock – the 1980 eruption of Mount St Helens was a phreatic eruption. (NPS)
There were explosions in 1790, the most lethal known eruption of any volcano in the present US. The 1790 explosions, however, simply culminated (or at least occurred near the end of) a 300-year period of frequent explosions, some quite powerful. (USGS)
Keonehelelei is the name given by Hawaiians to the explosive eruption of Kilauea in 1790. It is probably so named “the falling sands” because the eruption involved an explosion of hot gas, ash and sand that rained down across the Kaʻū Desert. The character of the eruption was likely distinct enough to warrant a special name. (Moniz-Nakamura)
The 1790 explosion led to the death of one-third of the warrior party of Kaʻū Chief Keōuakūʻahuʻula (Keōua.) At the time Keōua was the only remaining rival of Kamehameha the Great for control of the Island of Hawaiʻi; Keōua ruled half of Hāmākua and all of Puna and Kaʻū Districts. They were passing through the Kīlauea area at the time of the eruption. (Moniz-Nakamura)
Estimates of the number of fatalities range from “about 80 warriors” (William Ellis) to about “400 people” or “800 warriors” (Stephen Desha) to “5,405 countrymen” (David Douglas, quoting an eyewitness, a Priest of Pele, in 1834.) The lower numbers are probably most realistic. The dead were warriors and family members of Keōua’s army bound for Kaʻū. (NPS)
The next subsidence of the caldera floor occurred in 1868, when large earthquakes shook the southern part of Hawaii and simultaneous eruptions occurred from Mauna Loa and Kilauea. An area about 6,200-ft wide on the central caldera floor sagged about 330-ft, and a deeper conical pit about 900 m wide and about 3,000-ft developed at its southwest end at Halemaʻumaʻu. (USGS)
The pit again filled, and by 1874 a lava shield at Halemaʻumaʻu had once again grown to about the elevation of the southern caldera rim. Minor subsidences in and around Halemaʻumaʻu occurred again in 1879, 1886, 1891, and 1894.
The subsidence of 1894 was followed by 13-years of dormancy and very subdued, episodic activity within the pit of Halemaʻumaʻu. (USGS)
Lava returned to Halemaʻumaʻu shortly after the 1924 explosions ceased, but instead of being sustained the activity was now episodic. A series of seven brief eruptions in the next 10-years reduced the depth of Halemaʻumaʻu from 390 to 150 m, and then no eruptions occurred for 18 years, from 1934 to 1952.
Sustained eruption from June to November of 1952 filled Halemaʻumaʻu with another 120 m of lava. A brief eruption in May-June 1954 added 6 m of lava in Halemaʻumaʻu and a thin lava flow on the caldera floor to the east (Macdonald, 1955) (USGS)
The eruption of Kīlauea volcano continues at two locations. In the park, the vent within Halemaʻumaʻu Crater is easily viewed from the overlook at the Jaggar Museum. The second location is the Pu’u ‘Ō’ō vent located 10 miles east of the summit, on the remote east rift zone of Kīlauea. This area is not accessible to the public.