A strong earthquake rattled much of the Big Island of Hawaii this morning, with the epicenter of the quake on the southeast slopes of the giant Mauna Loa volcano near the town of Pahala, Hawaii. Mauna Loa is considered to be the world’s largest active volcano and in recent weeks, it has shown an increase in seismic activity.
According to USGS, the magnitude 4.6 earthquake, which was originally rated a 5.0 magnitude event, struck at 9:07 am Hawaii time at a depth of 13.4 km. The epicenter was located just-off shore the famous Punaluʻu Black Sand Beach on the island’s Kaʻū district. Kaʻū is the largest and southern most district of the Big Island of Hawaii and is likely one of the most vulnerable to future activity from Mauna Loa.
Despite the intensity, the Honolulu-based National Weather Service’s Pacific Tsunami Warning Center says there’s no threat of tsunami to Hawaii from the earthquake. “An earthquake has occurred….no tsunami is expected. Repeat. No tsunami is expected. However, some areas may have experienced strong shaking,” their bulletin, issued 3 minutes after the earthquake read.
Mauna Loa is one of 5 volcanoes that make up Hawaii’s Big Island. The oldest volcano on Hawaii Island is Kohala, which is more than one million years old. Kilauea is the youngest, at an estimated 300,000-600,000 years old. Mauna Loa is the second youngest volcano on the island, estimated to be about 700,000 years old.
Mauna Loa is considered the largest active volcano on Earth, rising to 13,681 feet above sea level. Mauna Loa rises up from the ocean floor of the Central Pacific at a depth of about 3 miles. Because of the volcano’s significant mass, the ocean floor directly beneath Mauna Loa is depressed by another 5 miles. According to USGS, this places Mauna Loa’s summit about 56,000 feet above its base; the enormous volcano covers half of the island of Hawaii, also known simply as the “Big Island of Hawaii.”
Hawaiian Volcano Observatory (HVO) scientists with USGS continue to urge caution and preparation for the eventual day Mauna Loa will erupt again. “While an eruption of Mauna Loa is not imminent, now is the time to revisit personal eruption plans. Similar to preparing for hurricane season, having an eruption plan in advance helps during an emergency,” said HVO in an earlier statement.
In recent days, officials in Hawaii have urged people there to be prepared for the inevitable eruption of the volcano. Developing an action plan and packing a go-bag are among the many recommendations authorities are suggesting people on Hawaii pursue now.