Feature request: hot spots and plate rifting #68
Description
Right now there don't appear to be any mantle plumes or hots spots in the simulated tectonics. Hot spots:
- create oceanic island chains, a very recognizable feature of earth's surface, and may create other landmasses (e.g. iceland, where a hotspot is on a rift zone)
- drive volcanic activity, which contributes to geology in various ways (I know someone else was asking about mineral composition)
- induce or contribute to tectonic plate breakup (e.g., african great rift valley, which is driven by two hot spots iirc)
The last one is especially important. I don't think a hot spot alone is always necessary to form a rift, nor does its presence under a plate guarantee one. The extensional forces on the plate tearing it apart play a big (maybe even bigger?) role. And the thickness/density of the plate also influences whether a hot spot can initiate rifting. But fortunately you already simulate those other two features! And there is a characteristic geography that forms when a rift involves a hotspot: three rift arms spread out from the hotspot, two meet plate boundaries and divide the plate and the third becomes a failed rift arm.
Failed rifting events are also important, though I can't tell if you're already simulating those. But they create a lot of interesting geography, especially large inland lakes or seas (the great lakes, lake baikal, the mediterranian/black seas, the baltic sea and gulf of bothnia. I don't know the degree to which hotspots were involved in all of them, but they're all failed rifts!