30.2 Precambrian and Cambrian Time

Chapter 30 Section 2
Precambrian and Paleozoic
-Compare and contrast the characteristics of Precambrian time and the
Paleozoic Era
-Identify major events in early geologic time
Precambrian – time that includes all geologic time before the start of the
Cambrian period in the Paleozoic Era (Its not a unit of geologic time but a
common way to refer to the Proterozic and Archean Eons)
-Lasts 4 billion years
-Rocks difficult to interpret
-Lack index fossils
-Often are bent and folded
-Economically important
-Iron, Copper, Gold and others mined from Precambrian rocks
Stromatolites – Precambrian fossils made up of cyanobacteria trapped in
domes or columns of sediments
Paleozoic Era:
Includes 6 periods:
-Index fossils include
-Trilobites (crablike invertebrate)
Take notes for each Period (highlight 3 points/events for each period)
Ordovician Period
Silurian Period
Devonian Period
Carboniferous Period
Permian Period