Great Southern Fissure Trap

Disaster / Destruction

A massive fissure opening, releasing molten rock and toxic chemicals into the southern ocean.

Up until this point in the planet’s history, a small portion of the western most parts of the southern sea had begun to pull away from it. This would continue, until a massive fissure opened up and released harmful contaminants, must notably hydrogen sulfide, into the ocean and resulting in the planet’s first mass extinction. In addition, the molten lava also released from the fissure isolated this body of water long before it had actually separated from the ocean, locking off the species seen in that region from the all the others.