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How old are rocks?
Absolute Dating | Earth Sciences Quiz - Quizizz
The oldest dated rocks formed on Earth , as an aggregate of minerals that have not been subsequently broken down by erosion or melted, are more than 4 billion years old, formed during the Hadean Eon of Earth's geological history. Meteorites that were formed in other solar systems can pre-date the Earth. Particles from the Murchison meteorite were dated in January to be 7 billion years old. Hadean rocks are exposed on the Earth's surface in very few places, such as in the geologic shields of Canada , Australia , and Africa. The ages of these felsic rocks are generally between 2. The approximate ages have a margin of error of millions of years.
Radiometric Age Dating
Lake Turkana has a geologic history that favored the preservation of fossils. Scientists suggest that the lake as it appears today has only been around for the past , years. The current environment around Lake Turkana is very dry. Over the course of time, though, the area has seen many changes. Over time the sediment solidified into rock.
Most absolute age determinations in geology rely on radiometric methods. The earth is billions of years old. The main condition for the method is that the production rate of isotopes stays the same through ages, i.
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