How do scientists think they know the age of the earth?
They can test the age of the rocks and find out when the oldest rocks started cooling from their liquid state, then use calculations involving the mass of the earth and the presumed temperature of the total ball of melted rock based upon the temperature of the core to figure out when earth started cooling.
Those who don’t know what Science is, often say things are ‘only theories’ as if to mean it is only a wild guess, but a Scientific Theory is better than a fact because it is based on Facts. Scientists don’t ‘know’ the age of the Earth, they have theories. There are many different ways they collect data but superstition is not one of them. — after reading other answers here, and noticing all the thumbs down, i just want to say, those who are giving the thumbs down to the scientific answers, are truly evil and foolish people.
Erosion. observation shows that erosion takes place at about 1 ft. every 5,000 years. Knowing this method, we can estimate the age of rock formations like the Grand Canyon. If the Canyon started out flat, it would take 30,000,000 years for the Colorado river to erode 600 ft of the Grand Canyon. Sedimentation. Another method used is to measure the rate at which sediment is deposited. Scientists think it takes between 500 and 10,000 years to deposit 1 foot of sediment. This method is not as accurate as the erosion method. Salinity of the oceans. Some geologists try to measure the age of the earth by the amount of salt in the ocean. First they need to find out how much salt is in the oceans. Then they find out how much salt rivers carry into the oceans each year. By comparing how much salt there is in the oceans now to how much is carried in by rivers each year, scientists can estimate the age of the oceans. Radioactive method.. One of the methods used is to study the uranium in igneous a
