click below
click below
Normal Size Small Size show me how
Chapter 10
vocabulary words
Term | Definition |
---|---|
Fossils | The preserved remains or evidence of ancient living things |
Catastrophism | Idea that conditions and organisms on earth change in quick violent events |
Uniformitarianism | States that geologic processes that occur today, are similar to those that occurred in the past |
carbon film | The fossilized carbon outline of an organism or part of an organism |
Mold | Impression in a rock left by an ancient organism |
Cast | Fossil copy of an organism made when a mold of an organism is filled with sediment or mineral deposits |
Trace fossil | Preserved evidence of the activity of an organism |
Paleontologist | Scientists who study fossils |
relative age | the age of rocks and geologic features compared with other rocks and features nearby |
superposition | the principle that in undisturbed rock layers, the oldest rocks are on the bottom |
inclusion | a piece of an older rock that becomes part of a new rock |
unconformity | surface where rock has eroded away producing a break or gap in the rock record |
correlation | matching rocks and fossils from separate locations |
index fossils | represent species that existed on earth for a short length of time, were abundant, and inhabited many locations |
absolute age | to mean the numeral age, in years of a rock or object |
isotopes | atoms of the same element that have different numbers of neutrons |
radioactive decay | the process by which an unstable element naturally changes into another element that is stable |
half life | the time required for half of the parent isotopes to decay into daughter isotopes |