Chapter 30 Section 2 Precambrian and Paleozoic Objectives: -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: Cambrian -Index fossils include -Trilobites (crablike invertebrate) -Brachiopod Take notes for each Period (highlight 3 points/events for each period) Ordovician Period Silurian Period Devonian Period Carboniferous Period Mississippian Pennsylvanian Permian Period