Evolutionists believe that the Earth is very old. There are many ages given but around 4-5 billion years is generally accepted by them. But the Earth doesn't look young or old! The Earth looks like the Earth. There is nothing that we can find that specifies how old it is or how young it is.
The beliefs and the resulting pre-conceptions of each person will allow them to see the Earth as they expect it to be!
Consequently evolutionists see a very old Earth, because they need that idea for their belief in evolution. And Christians see a very young Earth because that is what the Christian Bible says. There are also other ideas that are based on what people believe. And none of these people can 'prove' what they believe!
So which belief systems does the available science prove or disprove?
There are no absolute ways of knowing. Carbon dating can only be used for things that were once alive and which are not more than approximately 50 thousand years old (because there is no more C14 left to be measured for items before that time). There are many other factors that need to be taken into account to get an accurate reading, up to the 50 thousand year limit of course!
Radiometric dating of fossils is very easy to abuse. A researcher can take a number of sample rocks from around a fossil. When they test them they can simply pick those samples that give the age that they expect the fossil to be! They just ignore the other samples that do not fit their preconceived idea! After all what scientist would be brave enough to announce that they have found a fossil that is outside the time period that the species lived!
Other ways to estimate the age of rocks is to measure isotope concentrations and these measurements can be made very accurately. The problem here is that there are some assumptions that have to be made. We have to assume that we know the isotope concentrations in the original sample. We also have to assume that the rate of decay was constant and that no isotopes were lost or gained in the time.
There is another consideration when estimating the age of the earth from these dating methods. If one accepts Christian Creation then the earth was made with all the radioactive material within it. Measuring that material now and estimating the age from it would be flawed because no one knows the level of radioactivity present at the point the earth was created! There is no reason to assume that God created all the radiation 'brand new'. So calculating half-lives back through millions of years does not conflict in any way with a 'young' earth created by God.
Another approach is to look at the 'wear and tear' of planet Earth. We can look at various situations where we have a known rate of change, and apply that rate of change back through time. We come up with a number of interesting observations including:
- The continents are eroding too quickly.
- There is not enough helium in the atmosphere.
- There is not enough sodium in the oceans.
- There is too much helium in minerals.
Please see this link for a more complete discussion
An interesting result from the 1980 Mt. St. Helens eruption was the rapid deposition and erosion that that occurred over a couple of weeks after the eruption. Stratified layers up to 400 feet thick formed as a result of landslides, pyroclastic flow, mudflows, etc.
A deposit more than 25 feet in thickness, and containing upwards of 100 thin layers accumulated in just one day on June 12, 1980.
The eruption, monitored extensively by scientists, shows that the Grand Canyon and the Rift Vallley could have been formed in a similar way in just a few weeks! No longer can thousands of years be assumed for the formation of rock layers! The geological age of the Earth can be significantly reduced because scientists have now been able to monitor and measure an event that took place in their lifetime.
Genesis describes a scenario where planet Earth was hit by a cataclysmic flood. It broke up the crust of the planet. The flood waters would have swept all the organic material (trees, plants and animals) into the depths of the oceans. This of course is the source of our oil and coal reserves that have been so important in modern society. This is why so many fossil beds include fish, animal and plants all mixed together.
We can use science to understand as much as possible about the physical world we live in. But faith is not scientific! If people could prove that the Christian God exists then they wouldn't need any faith to accept God! It seems obvious to me that everyone would believe in Christianity if we could prove that God exists!
If the science supports the belief system then that is OK. But don't throw the baby out with the bathwater if it doesn't! For example the Catholic church has recently adopted evolution-based ideas to replace belief in Genesis 1-12. In my view this was a panic response to scientists claiming that evolution was a proven fact. Now scientists are beginning to see how complex the cells are, how DNA operates and how these systems cannot possibly be derived from incremental changes over a long period of time (evolution). So is the Catholic Church going to keep their faith in evolution, or go back to the Bible as their authority? Either way will be embarrassing for them!
Interesting articles in the Answers in Genesis site with some answers to these questions.
Answers in Genesis - various Questions and Answers
Answers in Genesis - Young Earth