First, radiometric dating methods do not prove an earth that is millions of years old. For years, creation scientists – including our own PhD scientists -- have done their own field research and have cited numerous examples in the published scientific literature of these dating methods clearly giving erroneous dates (e.g., a date of millions of years for lava flows that occurred in the past few hundred years—or even decades). In recent years, creationists in the RATE project have done experimental, theoretical, and field research to uncover more such evidence (e.g., diamonds and coal, which the evolutionists say are millions of years old, were dated by carbon-14 to be only thousands of years old) and to show that decay rates were orders of magnitude faster in the past, which shrinks the millions of years to thousands of years, confirming the Bible.
Some additional arguments for a young earth include:
--Comets disintegrate too quickly
According to evolutionary theory, comets are supposed to be the same age as the solar system—about five billion years. But each time a comet orbits near the sun, it loses so much material that it could not survive much longer than about 100,000 years. Many comets have typical ages of less than 10,000 years.
Evolutionists propose an “Oort cloud” that generates new comets to overcome this problem, but nobody has seen such a cloud. It’s just a convenient guess.
--Not enough salt in the seas
Every year, rivers and other sources of water dump over 450 million tons of sodium into the ocean. If the sea had no sodium to start with, it would have accumulated its present amount in less than 42 million years at today’s rates of input and output. This is much less than the evolutionary age of the ocean (which is about 3 billion years). The usual reply to this discrepancy is that past sodium inputs must have been less and outputs greater. However, calculations that are as generous as possible to evolutionary scenarios still give a maximum age of only 62 million years.