Fossil Test Flashcards
(21 cards)
Studies fossils and reconstruct the appearance of animals.
Paleontologist
Remains,imprints,or traces of prehistoric organisms
Fossils
Fossils in which spaces are filled with minerals from groundwater are called….
Per mineralized fossils
Thin film or carbon residue forms a silhouette of the original organism
Carbon film
Cavity in rock left when the hard parts of an organism decay
Mold
If sediments wash into a mold, they can form a ____ of the original organism
Cast
Occasionally ____ remains are preserved in a material such as amber,ice, or tar
Original remains
Evidence of an organisms activities
Trace fossils
Tracks left in mud or sand that become stone or burrows made by worms or other animals are also____
Trace fossils
Abundant, geographically widespread organisms that existed for relatively short periods of time
Index fossils
Process of reading undisturbed rock layers
Superposition
How old something is in comparison with something else is it’s
Relative age
Gaps in rock layers
Unconformities
Rock layers are tilted, and younger rocks are formed over it is called an
Angular conformity
A layer of horizontal rock once exposed and eroded before younger rocks formed over it is called a
Disconformity
Sedimentary rock forms over eroded metamorphic or igneous rock
Non conformity
Age, in years, of a rock or other object; determined by properties of atoms
Absolute age
Unstable isotopes break down into other isotopes and particals in the process of
Radioactive decay
The time it takes for half the atoms in an isotope to decay is the isotopes
Half life
Calculating the absolute age of a rock using the ratio of parent isotope to daughter product and the half life of the parent is called
Radiometric dating
Principle that earth processes occurring today are similar to those that occurred in the past
Uniformitarianism
