1. http://go.flvs.net/webapps/login/?action=defa ult_login MODULE 5 TIME TERMS EXPLAINED Absolute time – absolute means unconditional. Absolute time is exact time that does not rely on any other measure of time. Relative time - relative means has some connection to. Relative time must be related to some other value of time already known. Superposition – Super means above, position means location. The above position had to be placed on something that already existed. Faunal Succession – Faunal means of an animal, succession means to follow. Something had to follow (or be of the same time as) about the time of the animal Original Horizontality – Original means beginning, horizontal means flat or level. Something had to be flat or level when it started. Uniformitarianism – Uniform means consistent. Consistent patterns of time that happen over and over.

2. http://go.flvs.net/webapps/login/?action=defa ult_login MODULE 5 TIME PERIODS Precambrian - Pre means before, Cambrian is the time of widespread animal diversity beginning. So this is the beginning of the earth before the beginning of most animals. Paleozoic - Paleo means old or ancient, zoic means related to animal life This is the beginning of multi-celled animal life. Mesozoic – Meso means middle. This is time of the middle animals, such as dinosaurs. Cenozoic – Ceno means recent. This is the most recent time period, and refers to the development of most mammals including man.

3. http://go.flvs.net/webapps/login/?action=defa ult_login MODULE 5 RADIOMETRIC DATING Isotopes – Individual atoms that have different numbers of neutrons in the nucleus – sometimes a large number of isotopes can cause the atom to be unstable which leads to the change/decay process. Protons – Positively charged sub-atomic particles – in the nucleus Neutrons – Neutrally (or no) charged sub-atomic particles – in the nucleus Electrons – Negatively charged sub-atomic particles – surrounds the nucleus

4. http://go.flvs.net/webapps/login/?action=defa ult_login MODULE 5 RADIOMETRIC DATING Half Life – The amount of time it takes for half of the atoms in a sample to change/decay from parent element to daughter element It is an absolute amount of time. Each element has it’s own specific half life. Parent Element – The original element (unstable due to isotopes). Daughter Element – The final element (stable). Radiometric Dating - Radio refers to the radiant energy given off when the nucleus breaks up, metric refers to a form of measurement. The radiant energy given off causes the change/decay from the parent element to the daughter element. So, Radiometric Dating means measuring the change /decay that occurs from one element (parent element) to another element(daughter element) and then measuring the amount of time based on the amount of change/decay. The next slide shows a demonstration of a parent element’s decay over 3 half lives of time.