Why doesn radiometric dating work on sedimentary rocks
The most widely known form of radiometric dating is carbon14 datingthis is what archaeologists use to determine the age of humanmade artifacts but carbon14 dating wont work on dinosaur bones the halflife of carbon14 is only 5730 years so carbon14 dating is only effective on samples that are less than 50000 years old.
Because most sedimentary rocks are composed of sediment which derived from many sources any dating process would find many different results for example a zircon from a sedi mentary rock may have been formed in an igneous rock many hundreds of millions of years before.
sedimentary rocks cannot be dated directly using radiometric dating which is based on the idea that when rocks are in liquid form their radiometric clock resets this technique is generally used to date igneous and metamorphic rock which are rocks that were once melted due to extreme heat and pressure.
If an igneous or other rock is metamorphosed its radiometric clock is reset and potassiumargon measurements can be used to tell the number of years that has passed since metamorphism carbon14 is a method used for young less than 50000 year old sedimentary rocks.
sedimentary rock is composed of the weathered remains of a variety of rocks of all ages it would therefore only be possible to date specific components of a sample none of which would equate to.
radiometric dating of rocks and minerals using naturally occurring longlived radioactive isotopes is troublesome for youngearth creationists because the techniques have provided overwhelming evidence of the antiquity of the earth and life some socalled creation scientists have attempted to show that radiometric dating does not work.