ERA PERIOD AGE (of start) Cenozoic Quaternary 1.6 my Tertiary 65 my Mesozoic Cretaceous 140 my Jurassic 205 my Triassic 250 my Paleozoic Permian 290 my Carboniferous 355 my Devonian 410 my Silurian 438 my Ordovician 510 my Cambrian 540 my

Carboniferous 355 -290 million years ago Life Dominant life includes: Trees, ferns, amphibians, air-breathing molluscs and insects Development of amniotic egg by early reptiles occurs Climate The early part of the Carboniferous, the Mississippian, was heavily marine due to a rise in sea level. The later part of the Carboniferous, the Pennsylvanian, is known for its vast coal swamps that later become the coal and petroleum that we use for energy. Geology The main rock types/ deposits in PA are limestone, coal, and shale.