This phenomenon is so simple I feel like an idiot trying to describe it but I want to know the name of the process so I can search for a video to understand it better.
Observations: Geologists measure the age of the earth by studying the layers of the earth’s crust. Archeologists dig down and find remnants of the past under layers of dirt.
Assumptions: There are younger layers of dirt on top of the earth’s crust and older layers underneath. This seems like a continuous natural cycle of creation of a new top layer of crust.
Question: Where does all the dirt that becomes the next layer of sediment come from? Where is this perpetual supply of new dirt coming from?
It’s not like there is an endless supply of dirt stored in the sky and it’s constantly falling.
Do winds lift layers of dirt from one area of the earth and drop that dirt in another? That would just be a dirt exchange where one area wouldn’t have new layers of crust and another area would. That doesn’t seem correct with how ubiquitous the concept of layers of crust is.
Is it volcanoes that shoot dirt from the earth’s mantle into the sky then it slowly settles on the ground creating the next layer? If so that would mean the oldest layers of the crust at the bottom become liquified then are expelled into the air and settle as the newest layer of crust in the “dirt cycle” of crust formation. This would make crust creation continuous so it’s plausible but doesn’t feel completely correct.
In: 4
Two primary drivers on a consistent basis and then big dumps from volcanoes every so often.
Organic matter breaks down. Leaves turn into dirt, just to help you remember that a little bit, as does most (pretty much all?) other organic matter that is broken down in the environment. That’s a shit ton of mass every year across much of the planet.
Dust/sand/wind blown sediment w/e you wanna call it is a huge element, probably the primary one but imagine it’s highly specific to different regions. What fuels the dust is all sorts of shit, rocks break down too. Plus then deserts. The Sahara alone is dumping dust all over the world, even if most ends up in oceans, it’s still 400-700 x 10^6 tons/year of dust just from the Sahara and twice that from all deserts combined and tons does end up on land (bringing nutrients and other good stuff in the process)
These things spread out over millions/bullions of years is how you get these layers and periods of volcanic activity are also obvious for this reason because they dump a ton in a short amount of time
Tectonics feels more like a shuffling of these layers ontop of eachother or apart (like Africa’s rift valley where we got tons of old human fossils from) rather than really creating the layers as you describe anyways but either way an element
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