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Alfred Wegener developed his theory of continental drift in the early 20th century. His theory wasn't well accepted at that time. Geologists of that time had their own not quite scientific ideas regar …

Helium (He) is formed by radioactive decay of uranium (U) and thorium (Th) to lead (Pb). There's another name for the nucleus of a 4He atom: It's an alpha particle. Alpha decay is one of the pathways …

If you ascribe to the giant impact hypothesis, which most scientists do, whatever rotation the Earth had prior to the formation of the Moon was lost thanks to that 'giant impact'. That was a massive i …

The simple answer: Because it is. There's a nice theory that explains why the rotation axis of a big gas giant is more or less coaligned with its orbital angular momentum vector. Those big gas giants …

I gather, but may be wrong, that the mass of earth at present increases by around 108kg/day. All else being equal, one would expect the earth to have gained a mass, since 75 million years ago, of: $$ …

In theory, if the Earth was a solid object, the Chandler wobble would be easy to understand. It's simply a result of the polhode rolling without slipping on the herpolhode lying in the invariable plan …

Japanese legend claims that typhoons twice save Japan from attempted invasions by Kublai Khan, once in 1274 and seven years later 1281. These divine winds ("kamikaze") are mixed in Japanese mysticism …

What is the reason for having silicon in so large quantity on earth surface? I'm assuming this is asking about the Earth's crust versus its mantle, rather than the crust versus the core, or the c …

One needs breathable air, drinkable water, and food to survive. Food as we know it was nonexistent prior to the Ediacaran, which began about 635 million years ago. Life was exceedingly primitive (sing …

The oldest ocean floor in the ocean is no more than 200 million years old. Ocean floor sometimes subducts into the Earth but other times gets lifted to eventually become solid land. Whale fossils have …

You need to be very wary of anything written in the non-scientific media about science. The media loves woo and controversy because those are the things that garners readers, and that in turn garners …

Here's a somewhat different looking graph, from Oxygen and Evolution, Robert A. Berner et al., Science 316, 557 (2007): The graph shows three marked drops in O2 levels, each corresponding to an ext …

I'm not quite sure if the question is asking about glacial, ice ages, or snowball Earth, and whether it's about the onset or end of a glacial period. I'll try to hit all three. Ice Ages and Milankovit …

It thus seems reasonable to say we are entering another Ice Age according to Milankovitch cycles. Some of the Milankovitch conditions would appear to make the Earth ripe for a new glacial epoch star …

It is widely thought that when the Earth first formed there was no continental crust. Subduction is largely responsible for the creation of continental crust. If true, and there is no reason to think …