2nd largest division of time, 4 of these
make up an eon
Scale that divides earth’s 4.6 billion
year history into intervals of time
The time it takes for ½ of a
radioactive sample to decay
Any naturally preserved evidence of life
Any object created when sediment fills
a mold and becomes rock-shows what
the outside of the organism looks like
Occurs when organism’s tissues are
completely replaced by minerals
4th largest division of time
Organisms that lived during a short well
defined span
3rd largest division of time, divides eras
Cavity in the ground or rock where a
plant or animal was buried
Any naturally preserved evidence of an
animal’s activity
Largest division of geologic time
Preserved feces from animals
WORD BANK: PERIOD, INDEX FOSSILS, COPROLITES, PETRIFICATION,
MOLD, ERAS, EPOCHS, GEOLOGICAL TIME SCALE, HALF LIFE, TRACE
FOSSIL, CAST, EONS, FOSSIL,
Principle that states that the same
geological processes shaping the Earth
today have been at work throughout all
Earth’s history
When internal forces slant rock layers
instead of folding them
Determines whether an object is older or
younger by comparing it to other objects or
events
Establishing the age of a rock or fossil by
determining the # of yrs it has existed
Principle that states that all geological
change occurs suddenly
Process in which minerals fill in pore spaces
of an organisms tissue
An ideal sequence of rock that contains all k
known fossils and rock formations on earth
arranged from oldest to youngest
Unstable isotopes that break down into
stable isotopes of other elements
Atoms of the same element that have the
same # of protons but different neutrons
A break along Earth’s crust in which blocks
of crust slide relative to one another
The principle that states that younger
rocks lie above older rocks
Calculating the age of rock based on the the
percentage of parent material to daughter
material
Molten rock that squeezes between existing
rock layers and cools
Word bank: INTRUSION , RADIOMETRIC DATING, UNIFORMITARIANISM,
ISOTOPES, SUPERPOSITION, TILTING, GEOLOGICAL COLUMN, CATASTROPHISM,
ABSOLUTE DATING, RELATIVE DATING, RADIOACTIVE DECAY, FAULT,
PERMINERALIZATION
Vocabulary word
definition
Exists between horizontal rock
layers and rock layers that are
tilted or folded
illustration
Exits where part of a sequence
of parallel rock layers is missingcommon buy hard to see
A surface that represents a
missing part of the geological
column- represents time that
was not recorded in rock layers
Exists where sedimentary rock
layers lie on top or an eroded
surface of non layered igneous
or metamorphic rock
NONCONFORMITY, UNCONFORMITY, ANGULAR UNCONFORMITY,
DISCONFORMITY