Relative dating answers what age are rocks?
Absolute dating answers how old are the rocks?
Strata: rock units
distinguished by some
physical, chemical, or
palaeontological property, units of time are based on ages of strata
Correlation: correspondence between geographically separated parts of stratigraphic unit
Geochronologic (time) units:
– Interval during which a time-rock unit is formed
– Early and late
Chronostratigraphic (time-rock) units:
– All the strata in the world deposited during a particular interval of time
– Upper and lower
Stratigraphic range: total vertical interval in which a species occurs, form lowermost to