Eruptions of Mauna Loa have historically been characterized by high volume flows that produce lava capable of travelling long distances, contributing to its shape. Scientists believe that 90 percent of the volcano's surface has been covered with flows that erupted within the past 4,000 years.

Why is Mauna Loa considered active?

Mauna Loa is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. It has produced large, voluminous flows of basalt that have reached the ocean eight times since 1868.

What is the activity of Mauna Loa?

Activity Summary: Mauna Loa Volcano is not erupting. Rates of seismicity at the summit remain at long-term background levels. Other monitoring data streams—ground deformation, gas discharge, and visual observations—show no significant changes.