Relative vs absolute dating for kids
Relative vs absolute dating for kids - software internet dating
The main relative dating method is stratigraphy (pronounced stra-TI-gra-fee), which is the study of layers of rocks or the objects embedded within those layers.This method is based on the assumption (which nearly always holds true) that deeper layers of rock were deposited earlier in Earth's history, and thus are older than more shallow layers.
Both are attempting to get information on the history of events.Once students begin to grasp "relative" dating, they can extend their knowledge of geologic time by exploring radiometric dating and developing a timeline of Earth's history.Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years.Once they are able to manipulate the cards into the correct sequence, they are asked to do a similar sequencing activity using fossil pictures printed on "rock layer" cards.Sequencing the rock layers will show students how paleontologists use fossils to give relative dates to rock strata.Before radiometric dating it was difficult to determine the actual age of an object.
Radiometric dating, based on known rates of decay of radioactive isotopes in objects, allows a specific age of an object to be determined to some degree of accuracy.Mountains have been built and eroded, continents and oceans have moved great distances, and the Earth has fluctuated from being extremely cold and almost completely covered with ice to being very warm and ice-free.These changes typically occur so slowly that they are barely detectable over the span of a human life, yet even at this instant, the Earth's surface is moving and changing.However, by itself a fossil has little meaning unless it is placed within some context.The age of the fossil must be determined so it can be compared to other fossil species from the same time period.Although most attention in today's world focuses on dinosaurs and why they became extinct, the world of paleontology includes many other interesting organisms which tell us about Earth's past history.