Hawaiian eruption

Definition

A Hawaiian eruption is a type of volcanic eruption characterized by the effusive flow of low-viscosity basaltic lava, resulting in broad, gently sloping shield volcanoes. This eruption style is typically non-explosive and produces extensive lava flows that can travel over long distances, shaping the landscape and forming features such as lava tubes and pāhoehoe flows. The gentle nature of these eruptions contrasts sharply with more explosive types, allowing for unique lava formations and a generally safer environment for observers.

5 Must Know Facts For Your Next Test

1. Hawaiian eruptions primarily occur at shield volcanoes such as Mauna Loa and Kilauea, which are known for their large size and gentle slopes.
2. The lava produced during Hawaiian eruptions can create various flow types, including pāhoehoe and ʻaʻā, each with distinct physical characteristics.
3. The low viscosity of basaltic lava allows it to flow easily and rapidly across the landscape, contributing to the expansive nature of Hawaiian volcanic activity.
4. Hawaiian eruptions can produce features like lava tubes, which form when the surface of a lava flow cools while molten lava continues to flow underneath.
5. These eruptions are often accompanied by spectacular fire fountains, where gas pressure causes bursts of lava to shoot into the air before falling back down.

Review Questions

• What are the defining characteristics of a Hawaiian eruption compared to other types of volcanic eruptions?
  • Hawaiian eruptions are characterized by the effusive outpouring of low-viscosity basaltic lava, resulting in broad shield volcanoes. In contrast to explosive eruptions that release ash and pyroclastic material, Hawaiian eruptions produce gentle lava flows that can travel great distances. This creates distinctive landforms like lava tubes and various flow types such as pāhoehoe and ʻaʻā.
• How do the physical properties of basaltic lava influence the formation and behavior of Hawaiian eruptions?
  • The physical properties of basaltic lava play a crucial role in Hawaiian eruptions due to its low viscosity. This allows the lava to flow smoothly and easily, creating extensive lava fields and shaping the landscape into gently sloping shield volcanoes. Additionally, the fluidity facilitates the formation of unique features like pahoehoe flows and lava tubes, demonstrating how these properties directly impact volcanic behavior.
• Evaluate the ecological and geological impacts of Hawaiian eruptions on their surrounding environments.
  • Hawaiian eruptions have significant ecological and geological impacts on their environments. The extensive lava flows can reshape landscapes, creating new landforms and altering drainage patterns. Ecologically, these eruptions can lead to both destruction and regeneration; while they may initially obliterate existing habitats, they also create new environments that promote biodiversity over time. This dual impact highlights how Hawaiian eruptions contribute to both geological evolution and ecological dynamics in volcanic regions.

Related terms

Basalt: A dark, fine-grained volcanic rock that forms from the rapid cooling of basaltic lava, typically associated with Hawaiian eruptions.

Shield Volcano: A broad, gently sloping volcano built up by the accumulation of low-viscosity lava flows, characteristic of Hawaiian eruptions.

Pāhoehoe: A type of lava flow that is smooth and billowy, formed by low-viscosity lava, often seen in Hawaiian eruptions.