# Chapter 9 GEOL

### Chapter 9 GEOL

Which era are we currently in?

Precambrian
Cenozoic
Paleozoic
Mesozoic

Cenozoic
What is the definition of relative dating?

Counting tree rings to determine an age
Calculating dates based on the theory of relativity
Using radioactive materials to determine an age
Putting events in order from first to last

Putting events in order from first to last
Match the relative dating principles with the correct definition.
Unconformities

Missing time
The oldest is on the bottom, the youngest on top
Chunks of weathered rock are older than the rock they are contained in
Faults, fractures are younger than the rocks they cut through
Sedimentary layers/lava flows are deposited in flat layers
Rock extend in all directions until they reach the edge of a basin or pinch out

Missing time
A worm burrow is an example of which type of fossilization?

Mummification
Cast and Mold
Carbonization
Trace Fossil

Trace fossil
T/F – The fossil record is biased toward preserving organisms with hard parts.
True
What is correlation?

Matching up rocks of similar age in different regions
Matching up continental coasts based on matching shapes
Dividing up rock layers into new ones based on mineral content
Putting events in order from first to last

Matching up rocks of similar age in different regions
When correlating rock between widely separated areas or between continents, what feature do geologists rely on the most?

Mineral content
Sedimentary structures
Fossils
Rock type

Fossils
Match the relative dating principles with the correct definition.
Lateral Continuity

Missing time
The oldest is on the bottom, the youngest on top
Faults, fractures are younger than the rocks they cut through
Sedimentary layers/lava flows are deposited in flat layers
Chunks of weathered rock are older than the rock they are contained in
Rock extend in all directions until they reach the edge of a basin or pinch out

Rock extend in all directions until they reach the edge of a basin or pinch out
Match the relative dating principles with the correct definition.
Cross-Cutting Relationships

The oldest is on the bottom, the youngest on top
Sedimentary layers/lava flows are deposited in flat layers
Missing time
Rock extend in all directions until they reach the edge of a basin or pinch out
Chunks of weathered rock are older than the rock they are contained in
Faults, fractures are younger than the rocks they cut through

Faults, fractures are younger than the rocks they cut through
Match the relative dating principles with the correct definition.
Inclusions

Missing time
Chunks of weathered rock are older than the rock they are contained in
Sedimentary layers/lava flows are deposited in flat layers
Faults, fractures are younger than the rocks they cut through
The oldest is on the bottom, the youngest on top
Rock extend in all directions until they reach the edge of a basin or pinch out

Chunks of weathered rock are older than the rock they are contained in
What is an index fossil?

Organisms that are restricted to one small, geographic setting
Organisms that were geographically widespread but limited to a short span of geologic time
Trace fossils that define a colony of organisms
Organisms that existed for a vast period of time and are representative of an era

Organisms that were geographically widespread but limited to a short span of geologic time
What is an isotope?

An atom that has more or fewer electrons than it should
An atom that has more or fewer neutrons than it should
A nucleus of an atom that has split during the decay process
An atom that has double the protons of a stable atom

An atom that has more or fewer neutrons than it should
What is a fossil?

Mudcracks preserved in sedimentary rock
A really old geologist
Evidence of past life that can include skeletal as well as trace material
Only the hard parts of a skeletal structure that have been preserved

Evidence of past life that can include skeletal as well as trace material
Match the relative dating principles with the correct definition.
Superposition

Rock extend in all directions until they reach the edge of a basin or pinch out
The oldest is on the bottom, the youngest on top
Sedimentary layers/lava flows are deposited in flat layers
Faults, fractures are younger than the rocks they cut through
Missing time
Chunks of weathered rock are older than the rock they are contained in

The oldest is on the bottom, the youngest on top
T/F – The first life on Earth developed during the Cambrian Period.
False
A mammoth frozen in the Arctic tundra of Siberia would be an example of which type of fossilization?

Carbonization
Mummification
Replacement
Permineralization

Mummification
________ is a term used to define 88% of Earth’s history prior to the start of the Paleozoic Era.

Jurassic
Precambrian
Quaternary
Paleogene

Precambrian
T/F – Rapid burial is an important condition favoring preservation.
True
T/F – In cast and mold fossilization, the cast is the hollow space in the rock that subsequently becomes filled with mineral matter.
False
Match the relative dating principles with the correct definition.
Original Horizontality

Sedimentary layers/lava flows are deposited in flat layers
Rock extend in all directions until they reach the edge of a basin or pinch out
The oldest is on the bottom, the youngest on top
Faults, fractures are younger than the rocks they cut through
Chunks of weathered rock are older than the rock they are contained in
Missing time

Sedimentary layers/lava flows are deposited in flat layers