While it also has some basaltic lava flows, andesite is the dominant type.

Here's why this is important:

* Andesite lava is viscous and explosive. This contributes to Lascar's history of frequent and powerful eruptions.

* The composition of the lava tells us about the volcano's origins. Andesite magma is formed by partial melting of the Earth's crust, making Lascar a subduction zone volcano.

Let me know if you have any other questions!