Images and Video Show Indonesia's Most Active Volcano Mount Merapi Erupting

Dramatic images have emerged of a huge ash plume emerging from Mount Merapi, Indonesia's most active volcano, which erupted twice on Saturday.

Indonesia's Center for Volcanology and Geological Hazard Mitigation said the eruptions lasted around seven minutes, and spewed ash up to around 20,000 feet into the atmosphere, AFP reported.

Ash blanketed several villages surrounding the volcano, which is located on the densely populated Indonesian island of Java, while residents in neighboring areas reported hearing deep rumbling sounds.

Local authorities implemented a no-go-zone around Mount Merapi, advising villagers—thousands of whom live on the volcano's fertile flanks—to stay at least 1.8 miles away from the crater.

Authorities also warned locals to look out for lava flows, Sky News reported. However, they did not raise the alert status of the volcano, which has remained at its third highest level since August, 2019.

Although Indonesian authorities did not raise the volcano's alert status, they did warn commercial planes flying in the area to be cautious.

Mount Merapi—located in the center of Java, around 20 miles north of the city of Yogyakarta, whose metropolitan area is home to more than four million people—is one of the world's most active volcanoes, and the most active in Indonesia, having erupted regularly since the mid-1500s.

In fact, Merapi is one of 16 "Decade Volcanoes" identified by the International Association of Volcanology and Chemistry of the Earth's Interior as being particularly worthy of study due to their history of destructive eruptions and proximity to populated areas.

Other volcanoes on the list, include Mauna Loa in Hawaii, Mount Rainier in Washington state and Mount Vesuvius in Italy.

In March, eruptions at Merapi—the name of which means "Mountain of Fire" in Indonesian and Javanese—forced the closure of an airport in the city of Surakarta, Central Java.

A series of eruptions in late 2010 killed more than 350 people, and forced authorities to evacuate around 280,000 residents living in the areas surrounding the volcano. In 1930, an eruption produced pyroclastic flows that destroyed thirteen villages and killed more than 1,300 people.

Pyroclastic flows are avalanches of hot ash, gas and rock that sweep down the mountain at high speeds. Pyroclastic flows, alongside a similar phenomenon known as lahars—lethal, volcanic mudflows—have been responsible for much of the destruction caused by eruptions at Merapi, which rises to more than 9,500 feet.

Indonesia, a country consisting of more than 17,000 islands, is particularly volcanically and seismically active, lying at the meeting point of four tectonic plates—giant slabs of the Earth's crust. The country is home to around 130 active volcanoes.

It forms part of the "Ring of Fire"—a long, horseshoe-shaped, seismically active belt that extends around the Pacific Ocean basin along which many earthquakes and volcanic eruptions occur.

Mount Merapi eruption, Indonesia
This picture taken in Sleman, Yogyakarta on June 21, 2020 shows clouds of ash rising from Mount Merapi during an eruption. RANTO KRESEK/AFP via Getty Images