Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years. Mountains have been built and eroded, continents and oceans have moved ...

Potassium-argon dating of igneous and metamorphic rocks with applications to the basin ranges of Arizona and Sonora / P.E. Damon -- A comparison of the isotopic mineral age variations and petrologic ...

Using a method applied directly to ancient hominin teeth, researchers have calculated the age of several important fossils. Measuring the concentration of radioactive elements in a single, sand-size ...