I heard this too and somehow just accepted it, even though I could not imagine how this should have happened. So during this major extinction event all the big dinosaurs just gathered in giant groups, fell over, then never really decomposed but got covered with something and turned into coal, oil and gas?
Plankton is new to me too though. I thought it was plants, which could not be fully digested by anything at the time, so they just broke down a bit and formed layer after layer, until other organisms caught up and started digesting them completely - so this sort of concentrated organic matter doesn't exist in upper layers.
Plankton is new to me too though. I thought it was plants, which could not be fully digested by anything at the time, so they just broke down a bit and formed layer after layer, until other organisms caught up and started digesting them completely - so this sort of concentrated organic matter doesn't exist in upper layers.