At https://phys.org/news/2022-03-blobs-earth-mantle-unexpected-differences.html … within Earth’s Mantle there are two massive bob like structures, roughly on opposite sides of the planet. They are each around the size of a continent – and one hundred times taller than Mount Everest. One lies under Africa, and the other, under the Pacific Ocean. They are a puzzle.
Over at https://phys.org/news/2022-03-seafloor-fertilizer-factory-life-earth.html … theories on life on earth are being adjusted all the time. In this research paper, at https://doi.org/10.1038/s41561-022-00906-5... a microbial fertiliser factory on the seafloor is considered – at 2.6 billion years ago. In some ways, it is also an attempt to explain the rise in oxygen at 2.4 to 2.2 billion years ago. This is known as the Great Oxidation Event. One explanation is that it was initiated by rising levels of phosphorous in the oceans. This drove photosynthesis which then switched on oxygen production. Other researchers think it might have something to do with a declining rate of volcanism on early earth, releasing various gases. These assume oxygen increased as volcanoes subsided in numbers. The new study claims phosphorous in rocks at 2.6 billion years ago fueled photosynthetic bacteria, which preserved oxygen levels.