Here's why:
* Water content: Basaltic magma typically has a low water content, usually less than 1% by weight.
* Viscosity: This low water content contributes to basaltic magma's relatively low viscosity, meaning it flows more easily.
* Eruptions: This fluidity often leads to effusive eruptions, producing vast lava flows.
Contrast with other magmas:
* Rhyolitic magma: This type of magma is considered very "wet," with water contents often exceeding 5%. The high water content increases viscosity, making eruptions more explosive.
Important Note:
While considered dry, basaltic magma still contains some water, which plays a role in its behavior. The "wet" and "dry" classifications are relative terms used to compare water content across different magma types.
