784
« on: July 19, 2008, 04:59:14 pm »
Currently, when magma cools, it always forms obsidian.
However, there are lots of other types of igneous extrusive rock.
Have two types of magma vents, felsic and mafic. Mafic will flow faster than felsic, and forms different rocks when it cools. They will not be different types of lava, but instead tied to the regional biome information.
When felsic magma cools quickly, i.e. from water, it forms obsidian.
When it cools slowly, i.e. isolation from the source, it forms rhyolite.
Mafic magma will form basalt when it cools.
If the vent is a mafic-felsic mix, it will become andesite upon cooling.
Ideally, rhyolite volcanos should erupt more often than basaltic volcanos, but volcanos currently don't erupt.