Dakataua

Geography & Climate

Dakataua is located in Papua New Guinea, within the Bismarck Volcanic Arc of the broader Southwestern Pacific Volcanic Regions. Situated at 5.05° S, 150.10° E in the Southern Hemisphere, the volcano lies within a tropical climate zone. At just 408 meters above sea level, Dakataua is a relatively low-elevation volcanic feature. Despite its modest height, it remains an active geological formation with the same underlying magmatic processes as its taller counterparts. The volcanic landform is characterized as a caldera, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Dakataua sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Papua New Guinea near Dakataua, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Dakataua has 3 recorded eruptions in the geological database, spanning from 653 CE to 1895 CE. The most powerful recorded event was a colossal eruption capable of affecting global climate for years in 653 CE, reaching VEI 6 on the Volcanic Explosivity Index. These eruptions span roughly 1,242 years of volcanic history.

Significance

Dakataua has produced at least one eruption of VEI 6 or higher, placing it among the most powerful volcanic systems on Earth. Eruptions of this magnitude inject massive quantities of sulfur dioxide into the stratosphere, affecting global climate by lowering average temperatures for one to three years after the event.

GVP Reference Summary

The 10.5 x 13.5 km Dakataua caldera anchors the northern tip of the Willaumez Peninsula of New Britain. The latest episode of caldera formation occurred as recently as about 1,150 years ago, and was followed by at least five sub-Plinian or Vulcanian eruptions. A 12-km-wide freshwater lake whose surface is only about 50 m above sea level occupies the caldera. Two vertical fault-bounded blocks form topographic highs at the western and eastern sides of the caldera. A N-S line of post-caldera cones, explosion craters, and part of an arcuate inner caldera rim form a large peninsula that nearly bisects the arcuate caldera lake. The peninsula includes the 350-m-high andesitic Mount Makalia stratovolcano, the largest of the post-caldera cones, which last erupted during the late-19th century. A major submarine debris avalanche deposit NE of the volcano may represent edifice collapse prior to caldera formation. Thermal areas occur at several locations along the central peninsula.

— Smithsonian Institution, Global Volcanism Program