There are all sorts of clear indications against a young Earth.
One for misguided people to think of is the formation of stalactites. These are formed by droplets of water with a tiny amount of dissolved limestone evaporating before they drop. As such they can only grow at a very, very low pace. It just doesn't do to send water through more rapidly, because water only evaporates at a very limited rate (this is deep underground which has a very stable temperature all year round, and certainly never gets hot).
With this understanding, some known stalactites have taken around 200,000 years to form. Radiometric dating has provided an independent estimate of their age at 190,000 years which agreement provides support for both estimates.
That's a LOT longer than some people erroneously believe the Earth to have existed. But these stalactites do exist (and they are still growing at a similar extremely slow pace).
That is also a great point that I didn't even know almost anything about. So to overturn all this evidence the 6,000 year old earth theory needs a lot of proof and so far the 4.5 billion year model is proving far more accurate in almost all branches of science. (I say almost to be nice but I can't think of an example of a branch of science that argues for a 6,000 year old earth.)
There are all sorts of clear indications against a young Earth.
One for misguided people to think of is the formation of stalactites. These are formed by droplets of water with a tiny amount of dissolved limestone evaporating before they drop. As such they can only grow at a very, very low pace. It just doesn't do to send water through more rapidly, because water only evaporates at a very limited rate (this is deep underground which has a very stable temperature all year round, and certainly never gets hot).
With this understanding, some known stalactites have taken around 200,000 years to form. Radiometric dating has provided an independent estimate of their age at 190,000 years which agreement provides support for both estimates.
That's a LOT longer than some people erroneously believe the Earth to have existed. But these stalactites do exist (and they are still growing at a similar extremely slow pace).