Chpater 9 Flashcards
Who is Nicolas Steno?
A Danish anatomisg, studied a shark’s head and realized that the shark’s teeth resembled mysterious stone called “tonguestone.”
What is geology?
the study of rocks and rock formtions.
What is relative dating?
a method of putting events in the order in which they happened.
What is relative dating?
a method of putting events in the order in which they happened.
What is fossil?
the remains or traces of a dead animal or plant that has been preserved for a long time.
What is a paleontologist?
a scientist who studies and identifies fossils.
What does superposition mean?
the bottom layer of a rock formation is older than the layer on top, because the bottom layer formed first.
What does lateral continuity mean?
the idea that when layers of sediment are formed, they extend in all directions horizontally.
What does cross-cutting relationships mean?
a vein of rock that cuts across a rocks’ layer is younger.
What is a geologic time scale?
a model of Earth’s history.
What is absolute dating?
a method of measuring the age of an object in years.
What is radioactive decay?
refers to how unstable atoms lose energy and matter over time.
What is an element?
a substance composed of only one kind of atom.
What is half-life?
The amount of time it takes for half pf the unstable atoms in a sample to decay.
