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How Accurate is Carbon Dating?

Geologists do not use carbon-based radiometric dating to determine the age of rocks. Carbon dating only works for objects that are younger than about 50, years, and most rocks of interest are older than that. Carbon dating is used by archeologists to date trees, plants, and animal remains; as well as human artifacts made from wood and leather; because these items are generally younger than 50, years.

Carbon is found in different forms in the environment — mainly in the stable form of carbon and the unstable form of carbon Over time, carbon decays radioactively and turns into nitrogen.

Potassium argon method dating range – How to get a good woman. Developed in geochronology lays the effective time range from about my million years.

The problem : By the mid 19th century it was obvious that Earth was much older than years, but how old? This problem attracted the attention of capable scholars but ultimately depended on serendipitous discoveries. Early attempts : Initially, three lines of evidence were pursued: Hutton attempted to estimate age based on the application of observed rates of sedimentation to the known thickness of the sedimentary rock column, achieving an approximation of 36 million years.

This invoked three assumptions: Constant rates of sedimentation over time Thickness of newly deposited sediments similar to that of resulting sedimentary rocks There are no gaps or missing intervals in the rock record. In fact, each of these is a source of concern. The big problem is with the last assumption. The rock record preserves erosional surfaces that record intervals in which not only is deposition of sediment not occurring, but sediment that was already there who knows how much was removed.

Associated terminology: Conformable strata : Strata which were deposited on top of one another without interruption. Unconformity : An erosional surface that marks an interval of non-deposition or removal of deposits – a break in the stratigraphic sequence. Sequence : Group of conformable layers lying between unconformities. Unconformities are so common that today that sequence stratigraphy – the mapping and correlation of conformable sequences – is a major field in Geology.

With unconformities factored in, the age of the Earth would have to be much greater than 36 million years. Similar attempts yielded results that varied widely between 3 million and 1. Evolution stokes the fire : By the s century, the controversy surrounding evolution prompted new attention.