It is not as old as we are told.
Isotopic decay from uranium into lead, is the main means of dating rocks. This varies and is not constant, something that was not fully established until recently and the precise degree of modification of the constant half-life has yet to be established.
If the earth were thousands of millions of years old, with trees and higher animals around for 2 billion years, we would have flat continents and all would be under sea. All the detritus of life is called soil. Soils vary from hundreds of metres deep to nil. If life had been here for that length of time, there would be much more of it.
Another point: the blue whale we are told, is the largest ever animal to have existed, yet it is merely 20,000,000 years old. Dinosaurs were around for 200,000,000 years or so yet never reached that size despite their colossal land size.
The oceans are very recent and their formation and the cause of their origin, via ice, are one reason for earthquakes. Look at the ocean shelf around most continents and it shows the clear margin established for 10-20,000 years before the ice melted and submerged these fertile plains where cities were long ago established.