No Tsunami after 2 Earthquakes at Kīlauea, 4.8 and 3.2 Magnitude
By Wendy Osher
There is no tsunami threat to Hawaiʻi following a 4.8 magnitude earthquake reported in the Hilina Region of the Kīlauea Volcano on Hawaiʻi Island, according to the Pacific Tsunami Warning Center. The quake was reported at 5:54 a.m. on Sunday, Aug. 11, 2013, and was followed by a smaller 3.2 earthquake at 6:07 a.m. in the same region.
Additional Info from the USGS Hawaiian Volcano Observatory say the quakes were centered about 5 miles S of the summit area of Volcano, almost directly below the Kulanaokuaiki campground within the National Park.
Wes Thelen, HVO’s Seismic Network Manager issued a statement in an HVO press release saying, “These earthquakes were most likely structural adjustments of the Earth’s crust due to the weight of the island on the underlying mantle.”
He continued saying, “The earthquake likely occurred on a near-horizontal fault plane in the mantle, which has hosted earthquakes in this region before.”
Despite their location near Kīlauea’s summit, Thelen said, “it’s unlikely that the earthquakes were volcanic in nature due to their depth, which is below, and offset from, the volcano’s known magma plumbing system.”
HVO Scientist-in-Charge Jim Kauahikaua also commented saying that the earthquakes had no apparent effect on Kīlauea’s ongoing eruptions.
According to Kauahikaua and information released by the HVO, the larger event is only the second earthquake with a magnitude greater than 4 to occur at this location and depth since the start of Kīlauea’s ongoing East Rift Zone eruption in 1983.
The HVO notes that there were six such earthquakes in the 20 years before Kīlauea’s ongoing East Rift Zone eruption began.
The magnitude 4.8 earthquake was felt throughout the Island of Hawai`i, as well as on parts of Maui and O`ahu, according to the “Did you feet it?” reports tracked by the USGS.
***Supporting information courtesy Pacific Tsunami Warning Center, USGS, and Hawaiian Volcano Observatory.