2 billion BCE3 Aug 2020 13:40
By way of distraction, here is some of my learning over the weekend. I guess experts will already know lots about the geology of the Bushveld igneous intrusion. I was wondering what was life was on the planet at the time when it was produced about 2 billion years ago. The Great Oxidation Event (GOE) occurred about 2.0-2.1 billion years ago. Prior to the GOE, most existing lifeforms were anaerobic organisms. Oxygen produced by photosynthesis from e.g. cyanobacteria in the sea began to accumulate in the atmosphere from around 2.4 billion years ago, subsequently leading to extinction of many of the anaerobic organisms. Multicellular organisms began to appear around 1.7 billion years ago. The earliest complex land plants developed around 850 million years ago, and vertebrates about 525 million years ago. So, at the time when all of the molten goodies extruded upwards, there were probably just a load a single-celled organisms bobbing around like soup in the sea.