Ruang Volcano, a stratovolcano rising from the sea in Indonesia’s Sangihe Islands, was once a picture of tropical serenity. Dense rainforest covered its slopes, providing a habitat for a rich variety of plants and animals. This was all shattered in April 2024 when Ruang erupted after years of quiet. The volcano, known for its powerful eruptions, unleashed a series of explosive events that drastically changed the landscape, turning the island into an apocalyptic wasteland.
The first major eruption on April 16th sent a massive ash plume 20 kilometers high into the atmosphere. This was the volcano’s strongest eruption since 1871. The eruption was characterised by powerful pyroclastic flows, substantial ash plumes and intense volcanic lightning. The Indonesian Center for Volcanology and Geological Hazard Mitigation (PVMBG) noted that the eruption was particularly notable for its rapid escalation and the substantial volume of volcanic material ejected. Satellite imagery and ground-based observations revealed massive ash clouds spreading across the surrounding maritime region, posing significant aviation and environmental risks.
While the initial eruption in April caused significant disruption and displacement, Ruang wasn’t done yet. Just weeks later, at the end of April and into early May, the volcano erupted again with renewed force. This second eruption produced another massive ash plume, reaching even higher altitudes than the first, and further blanketing the surrounding islands in ash.
The aftermath of the eruptions was one of chaos and displacement. Around 16,000 residents from Ruang and Tagulandang were evacuated to safety just three hours prior to the first eruption.
The volcano remains in a state of unrest. Although no further eruptions have occurred, heightened seismic activity persists. Continuous degassing further suggests that the volcano’s internal system remains pressurised and volatile. While a period of quiet has settled over Ruang, the potential for renewed eruptive activity remains high.
Five months after Ruang Volcano’s dramatic eruptions, Extreme Pursuit achieved a remarkable feat, becoming one of the first teams to land on the island, successfully climb to the volcano’s summit, and observe the transformed crater firsthand.
Ruang Volcano degassing (October 2024)
Despite the impact of the pyroclastic flows, some plant life has managed to survive and is now quickly regenerating.
The devastation of Laingpatehi village was the first thing that hit us as we landed. Where a thriving community once stood on the island’s western tip, now lay ruin. It was a profoundly sobering sight and a stark reminder of why attempting to ride out a volcanic eruption is never a safe choice. The houses were simply gone. Corrugated iron roofs were shredded, and solid concrete foundations were pulverised into dust. With only hours to flee, the villagers left everything behind. They will never be able to return to their homes and will be relocated to Manado.
The climb was grueling. The heat was unbearable, and the dust was suffocating, infiltrating every piece of gear. As we neared the summit, the slope became so steep that we were forced to scramble on all fours.
A major fracture has developed near the summit, raising concerns about the possibility of further crater collapse.
After a two-and-a-half-hour climb, we finally conquered the summit and gazed down into the crater’s depths.
My drone successfully navigated the 220-meter descent to the crater floor, revealing vigorous degassing venting from multiple locations.
A reminder of the dangers of venturing too close to the crater’s edge: recent rockfalls have occurred.
Intrusion dike
Ruang Volcano presents a complex array of geological phenomena that needs in-depth scientific investigation. While the precise sequence of events leading to the recent eruptions remains to be fully understood, the landscape offers compelling clues. The presence of an intrusion dike suggests that magma forcefully penetrated pre-existing rock strata, contributing to the volcano’s instability and influencing the eruption pathways. Furthermore, the identification of a volcanic plug indicates that solidified magma choked the conduit at some point, possibly leading to a build-up of pressure and a more explosive eruption. The interaction of magma with groundwater is another critical area of study.