Geologic History: The Geologic Time Scale

self-check Self-Check: Interpreting Time of Geologic Maps

Practice interpreting time on geologic maps by studying the geologic map of New Jersey and then answering the questions below.

Geologic Map of New Jersey. The map includes a key with the following information: Sedimentary Rocks Cenozoic: Yellow = Holocene, Orange = Tertiary, Mesozoic: Light Green = Cretaceous, Grass Green = Jurassic, Blue = Triassic, Paleozoic: Light Blue = Devonian, Dark Blue = Silurian, Pink = Ordovician, Gray = Cambrian. The numbers 1, 2, 3 and 4 appear on the map. The number 3 is over an orange area. The number 2 is over a light blue area. The number 4 is over a yellow area and the number 1 is over a pink area.

Image courtesy of www.state.nj.us 2010

think icon
At what point are the oldest sedimentary rocks in NJ found?
 
Point 1
think icon
At what point are the youngest sedimentary rocks in NJ found?
 
Point 4
think icon
At which point were sedimentary rocks formed at about the same time that the dinosaurs became extinct?
 
Point 3