Several hundred years have passed since Haleakala last erupted. This movement has shifted Maui a few kilometers from a molten rock reservoir. Thus, eventually, Haleakala will become extinct. Today, earthquake records indicate internal adjustments are still taking place in the earth's crust. At present, however, no volcanic activity of any form is visible in the crater nor at any other place on the island of Maui.
Volcanoes spew noxious plumes of acidic gases.
The resulting vog and laze effect many communities across the county. When a volcanic erupts, sulfur dioxide within the molten rock is converted to sulfuric acid. Gases are also produced at the ocean. Both of these gases can contain particulate matter, such as volcanic glass or trace metals. Vog and laze are carried by winds across the county.