Index Fossils and Geologic Time (NYS Regents)

On top of Mt. Everest, there are fossilized remains of sea life; this tells us that the rocks at the top of world's highest mountain 

• used to be above sea level
• used to be below sea level
• used to be on Mars
• came from an asteroid

Which best describes a fossil that helps determine the relative age of a rock layer?

• trace fossil
• index fossil
• radioactive fossil
• unconformity fossil

How long ago did the Earth form, according to geologists?

• 3.6 million years ago

• 3600 million years ago

• 4600 million years ago

• 4.6 million years ago

Most fossils are found in __________ rock layers

• metamorphic
• sedimentary
• igneous
• igneous and sedimentary

Certain fossils existed all over the world, but only for a short period of geologic time.  If a geologist finds this fossil in a layer of rock, he/she will be able to tell how old that rock layer is.  These are called

• intrusion fossils
  casts
• imprint fossils
• index fossils
• intrest fossils

How do MOST fossils form? 

• living things die and their remains are quickly buried by sediments 
• the hard parts of an organism dry out in the air 
• the soft parts of an organism change to stone 
• freezing preserves the remains of an organism 

Which rock layer in the diagram seems to be the oldest?

• F
• E
• B
• C

Paleozoic, Mesozoic & Cenozoic are all

• Epochs
• Eras
• Periods
• Eons

The diagram represents the placoderm fish Bothriolepis, an index fossil found in New York State. What time period is this fossil from?

• Ordovician
• Silurian
• Devonian
• Cambrian

Valcouroceras is a New York State index fossil. Which mountain-building event occurred in New York State during the time when Valcouroceras was living in oceans covering parts of New York State? 

• Alleghenian orogeny  
• Taconian orogeny 
• Acadian orogeny
• Grenville orogeny