Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
10 Cards in this Set
- Front
- Back
|
Fossil |
Remains or traces of prehistoric life |
|
|
Relative dating |
Relative dating is the science of determining therelative order of past events
|
|
|
Uniformitisiam |
the theory that changes in the earth's crust during geological history have resulted from the action of continuous and uniform processes. |
|
|
Uniformity |
Represents a long period during which deposition stopped, erosion removed previously formed rocks, and deposition resumed |
|
|
|
|
|
|
Index fossil |
a fossil that is useful for dating and correlating the strata in which it is found |
|
|
Radioactivity |
the process by which the nucleus of an unstable atom loses energy by emitting radiation, including alpha particles, beta particles, gamma rays, and conversion electrons. |
|
|
Half life |
half-life of a radioactive substance is the amount of time it takes forhalf of its atoms to decay, and the half-life of a drug is the amount of time it takes before half of the active elements are either eliminated or broken down by the body. |
|
|
Era |
a long and distinct period of history with a particular feature or characteristic. |
|
|
Eon |
Eon, a variation of aeon, is defined as a unit of geological time equal to a billion years, or a very long period of time. An example of an eon is the unit of measure used when talking about how long ago the solar system was created. An example of an eon is the amount of time since dinosaurs roamed the earth. |
