<P> By May 31, 87 houses in Leilani Estates and nearby areas had been destroyed by lava . Advancing lava flows caused additional evacuation orders, including the town of Kapoho . By June 4, with the lava having crossed through Kapoho and entered the ocean, the confirmed number of houses lost had reached 159 . Two weeks later, the confirmed number of homes lost was 533, and as of June 25 it had risen to 657 . </P> <P> In conjunction with the outbreak of lava in lower Puna, a lava lake at Halema ʻumaʻu Crater at Kilauea's summit began to drop on May 2, 2018 . The Hawaiian Volcano Observatory warned that the lowering of the lava lake increased the potential for phreatic (steam) explosions at the summit caused by interaction of magma with the underground water table, similar to the explosions that occurred at Halema ʻumaʻu in 1924 . These concerns prompted the closure of Hawai ʻi Volcanoes National Park . On May 17, at approximately 4: 15 a.m., an explosive eruption occurred at Halema ʻumaʻu, creating a plume of ash 30,000 feet into the air . This marked the beginning of a series of vigorous explosions that have produced significant ash plumes from Halema ʻumaʻu . These explosions, accompanied by large earthquakes and inward slumping and collapse within and around Halema ʻumaʻu Crater, continued until early August . </P> <P> The Global Volcanism Program has assigned a Volcanic Explosivity Index (VEI; the higher the number, the more explosive) to all except five of Kīlauea's ninety - five known eruptions of the last 11,700 years . The eruption of 1790 has a VEI of 4 . The eruptions of 1820, 1924, 1959 and 1960 have a VEI of 2 . The eruptions of 680, 1050, 1490, 1500, 1610, 1868, four eruptions in 1961 and the current eruption since 1983 have a VEI of 1 . The other seventy - four eruptions have a VEI of 0 . </P> <Table> Volcanic Explosivity Index for Kīlauea <Tr> <Th> VEI </Th> <Th> Number of Holocene eruptions for which a VEI has been assigned (total = 90) </Th> </Tr> <Tr> <Th> VEI 0 </Th> <Td> 74 </Td> </Tr> <Tr> <Th> VEI 1 </Th> <Td> 11 </Td> </Tr> <Tr> <Th> VEI 2 </Th> <Td> </Td> </Tr> <Tr> <Th> VEI 3 </Th> <Td> 0 </Td> </Tr> <Tr> <Th> VEI 4 </Th> <Td> </Td> </Tr> </Table>

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