GENERAL GEOLOGY

Detailed explanation-1: -Relative dating is used to arrange geological events, and the rocks they leave behind, in a sequence. The method of reading the order is called stratigraphy (layers of rock are called strata ). Relative dating does not provide actual numerical dates for the rocks.

Detailed explanation-2: -To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.

Detailed explanation-3: -Superposition. This principle states that a sequence of rocks in their original orientation will have the oldest rock on the bottom and the youngest rock on the top.

Detailed explanation-4: -Stratigraphy is the study of the order of the layers of rocks and where they fit in the geological timescale. This method is most effective for studying sedimentary rocks. Cross dating is a method of using fossils to determine the relative age of a rock.

Detailed explanation-5: -The numerical ages of rocks in the Geologic Time Scale are determined by radiometric dating, which makes use of a process called radioactive decay – the same process that goes on inside a nuclear reactor to produce heat to make electricity. Radiometric dating works because radioactive elements decay at a known rate.