Dukono: The Forgotten Volcano of Halmahera - Constant Eruptions

Dukono is one of the world’s most active, yet least visited, volcanoes. Located on the northern tip of Halmahera island in Indonesia’s remote Maluku province, it has been erupting almost continuously since 1933.

While famous volcanoes like Bromo and Merapi attract thousands of tourists daily, Dukono remains a “forgotten giant.” It offers a raw, primitive volcanic experience for the few adventurers willing to make the difficult journey to reach it. There are no guard rails, no ticket booths, and often, no other people—just the deafening roar of the earth exploding.

Geological Context: A Complex Beast

Dukono is not a simple cone; it is a complex volcano with a broad, low profile.

• Structure: The summit area is a chaotic landscape of multiple overlapping craters. The active center is the Malupang Wariang crater (360 x 700 meters), which is constantly changing shape due to the relentless activity.
• Activity Style: Dukono’s activity is typically Strombolian to Vulcanian. It ejects ash, lapilli, and volcanic bombs in rhythmic explosions that can occur every few seconds or minutes. This continuous degassing creates a permanent plume of white and grey smoke that drifts over Halmahera.

A History of Noise and Ash

Since its awakening in 1933, Dukono has been a noisy neighbor.

• The 1550 Eruption: The first recorded eruption was a major event in 1550 (VEI 3), which produced a lava flow that filled the strait between Halmahera and the flank of Mount Mamuya.
• The Modern Cycle: The current eruptive phase, which began in 1933, is remarkable for its longevity. For nearly a century, Dukono has been throwing ash into the sky. This ash often damages local crops and forces the closure of the nearby Galela airport.

The Tectonic Engine

Dukono sits at a complex geological intersection responsible for its hyper-activity.

• The Halmahera Arc: It is part of the Halmahera Volcanic Arc, formed by the subduction of the Molucca Sea Plate beneath the Halmahera Plate. This double-subduction zone (the only one of its kind on Earth) creates a massive supply of magma.
• Magma Chamber: Seismological studies affirm the presence of a shallow, open-system magma conduit. This essentially means the “lid” is off the volcano, allowing gas and magma to rise freely without building up the pressure needed for a catastrophic, mountain-destroying explosion. Instead, it “leaks” constantly.

The 1933 Awakening

While the modern eruptive phase is often cited as starting in 1933, the lead-up was dramatic.

• Seismic Swarms: In late 1932, villagers in North Halmahera reported violent ground shaking that lasted for weeks.
• The Breach: In August 1933, the main Malupang Wariang crater cleared its throat. A series of paroxysmal explosions excavated the crater floor, merging several smaller vents into the single, roaring pit we see today. Since that date, the volcano has not stopped erupting for more than a few months at a time, making it one of the most persistent eruptive events in recorded history.

The Chemistry of the Plume

Dukono is a massive polluter.

• Sulfur Dioxide (SO2): It is one of Indonesia’s top emitters of SO2. The gas plume is so constant that it has created a “volcanic desert” downwind.
• Acid Rain: The local ecosystem has adapted to a constant drizzle of acid rain. Metal roofs in nearby villages corrode within a few years, and farmers must choose crops like coconut and nutmeg that are relatively resistant to the chemical fallout.
• Ash Composition: The ash from Dukono is rich in silica and sharp volcanic glass. While dangerous to engines and lungs, it is a mineral goldmine for the soil, contributing to the incredible fertility of Halmahera’s jungle once it weathers down.

Hiking Dukono: Into the Blast Zone

Trekking to Dukono is an expedition, not a day hike.

• The Journey: It usually starts from the village of Mamuya. The trail winds through cocoa and nutmeg plantations before entering dense, humid jungle.
• The Lahar: The path eventually leads into an old lahar (mudflow) channel. Hiking up this grey, river-like scar through the green jungle is surreal.
• The Summit: As you approach the top, vegetation disappears, replaced by a wasteland of black ash and volcanic bombs. The final push to the rim is steep and slippery.
• The Crater: At the rim, you are face-to-face with the active vent. You can see (and feel) lava bombs being ejected hundreds of meters into the air. Caution: It is critical to stay upwind. A shift in the wind can envelop you in suffocating sulfur gas and falling rocks.

Halmahera: The Spice Island

Dukono is located on Halmahera, the largest island in the Maluku chain (the legendary Spice Islands).

• History: This region was once the center of the global trade in cloves and nutmeg, sparking wars between European powers.
• Wildlife: The forests around the volcano are home to unique species like the Wallace’s Standardwing (a bird of paradise) and the giant Wallace’s Bee.
• Tobelo: The nearest major town is Tobelo, a dusty but friendly hub where you can arrange guides and transport. It is also a jumping-off point for exploring the pristine beaches and coral reefs of the surrounding islands.

The Phenomenon of Volcanic Lightning

Dukono is a prime location for observing volcanic lightning (dirty thunderstorms).

• Static Charge: The relentless ejection of sharp ash particles creates massive static electricity within the plume.
• The Display: At night, long arcs of purple and white lightning can be seen flashing inside the ash cloud, independent of any weather storm. This makes Dukono a favorite, albeit dangerous, subject for astrophotographers.

Living in the Shadow: Galela

The town of Galela, situated just northeast of the volcano, has a complicated relationship with the mountain.

• Historical Hub: In the 19th century, Galela was a major trading port for the Dutch East Indies.
• The Ash Reality: Today, life in Galela is dictated by the wind direction. When the wind blows north, the town is blanketed in grey grit. Residents wear masks, and schools often close. Yet, the soil is so fertile that the town remains an agricultural powerhouse, producing tons of coconut, nutmeg, and vanilla.

Flora of the Fallout Zone

How does nature survive constant eruption?

• Pioneer Species: The upper slopes are dominated by hardy ferns (Gleichenia) and coarse grasses that can survive being buried in ash.
• The Recovery Line: There is a sharp “trim line” where the jungle ends and the ash desert begins. As Dukono’s activity fluctuates, this line moves up and down the mountain, a visual barometer of the volcano’s health.

Hiking Safety Guide

If you are committed to climbing Dukono, you must be prepared.

• Gas Masks: A construction-grade respirator is not optional; it is mandatory. The SO2 concentrations can knock you unconscious in seconds.
• Eye Protection: Goggles are needed to protect against gritty ash.
• Guide: Never attempt this alone. The trail is often overgrown, and the “safe zones” on the rim change with the wind and the vent configuration. Local guides from Mamuya know the mountain’s moods.

Conclusion

Dukono is a volcano for the purist. It lacks the scenic symmetry of Fuji or the turquoise lakes of Kelimutu, but it makes up for it with sheer, unadulterated power. It is a place where you can witness the Earth building itself, rock by rock, explosion by explosion. For those who seek the wild and the untamed, Dukono is the ultimate destination.

The New Frontier: Drone Videography

Dukono has become a pilgrimage site for extreme drone pilots.

• The Challenge: The combination of magnetic interference from the magma, turbulent updrafts, and flying rocks makes it one of the hardest environments to fly in.
• The Archive: Footage captured by these daredevil pilots provides scientists with close-up views of the vent geometry that would be impossible to get otherwise. It’s a rare case where hobbyists directly contribute to scientific monitoring.

Soil Science: The Gift of Ash

Why do people stay? The soil.

• Andosols: The ash from Dukono weathers rapidly in the tropical heat, forming Andosols—soils capable of holding massive amounts of water and nutrients.
• The Nutmeg Trade: This volcanic soil is the secret behind the superior quality of North Halmahera’s nutmeg. The volcano essentially fertilizes the cash crops that drive the local economy, creating a dependency loop between the farmer and the fire.

Future Activity

What is next for Dukono?

• Steady State: Most models suggest Dukono will continue its current style of activity for decades. The open conduit system effectively regulates pressure.
• The Risk: The main danger is a sudden blockage of the vent (perhaps by a landslide). If the “lid” is put back on, pressure could build rapidly, leading to a much larger, Plinian-style eruption.

Quick Facts

• Location: North Halmahera Regency, North Maluku, Indonesia
• Coordinates: 1.693° N, 127.894° E
• Summit Elevation: 1,335 m (4,380 ft)
• Volcano Type: Complex Volcano
• Status: Continuous Eruption (Alert Level II or III usually).
• Difficulty: High (Remote, strenuous, hazardous).