|
|
Lava pours down a well-developed lava channel below a series of erupting vents (background) on the northeast rift zone of Mauna Loa Volcano. This channel fed an `a`a flow flow that reached 25 km from the vents; the channel width varied from 20 to 50 m. A scientist is standing near the channel (thin white vertical line in center). Fluid basalt flows may extend tens of kilometers from their source, and the leading edges of basalt flows can travel as fast as 10 km/hour on steep slopes. The flow front of a basalt flow on gentle slopes typically advances less than 1 km/hour. Where basalt lava flows are confined within channels or lava tubes, however, velocities within the channel or tube can be higher than 30 km/hour. |
