Geologic Time: Group 1: You have been assigned the entire geologic timescale. Please plot the major Eon boundaries and the following events: Event Earth forms Formation of the moon Oldest known zircon Oldest known rocks Period of major impact events on moon Oldest known banded iron formation (free oxygen in the ocean) Major interval of banded iron formations Snowball Earth events Ediacaran fauna Cambrian explosion (abundant marine organisms in the geologic record) Formation of Pangea (supercontinent) Gondwana glaciation and major coal deposits Largest Mass extinction in Earth history and outpouring of the Siberian Traps Rifting of Pangea (Triassic basins, e.g. Palisade sill; Central Atlantic Magmatic Province CAMP) Extinction of the Dinosaurs and outpouring of Deccan Traps Most recent glaciation of New York city Time in billions of years before present 4.56 4.45 4.4 4.0 3.9 3.8 2.4-1.8 0.713, 0.635, and 0.580 0.549-0.543 0.542 0.300 0.320-0.290 0.251 0.200 0.065 0.00002 **Note to all: The Deccan and Siberian Traps are examples of Large Igneous Provinces. Both are large volume outpourings of basaltic magma onto the surface of the Earth that are believed to have altered the chemistry and transparency of Earth's atmosphere. Group 2: You have been assigned the Paleozoic. Please plot the major Period boundaries and the following events: Event Precambrian-Cambrian boundary (~time of deposition of sedimentary and volcanic rocks in Central Park) Early fish Taconic Mountains (~time of high grade metamorphism of rocks in Central Park) Earliest land plants Deposition of Shawangunk Quartzite (rock climbing cliffs in New Paltz) Earliest fossil amphibians (i.e first animals on land!) Acadian Mountains (second period of high grade metamorphism in Central Parkformation of small granite bodies); deposition of sediments that form the Catskills Early trees, formation of coal deposits Reptiles! Alleghenian Mountains (Himalayan size mountains along current east coast of North America, major sedimentary deposits in Pittsburg PA) Gondwana glaciation and major coal deposits Final assemblage of Pangaea super-continent Emplacement of the Siberian Traps and the largest Mass Extinction event in Earth history! (Paleozoic-Mesozoic boundary) Time in millions of years before present 542 490 450 430 416 370 370-360 363-300 325 300 320-290 300-290 251 Group 3: You have been assigned the Mesozoic. Please plot the major Period boundaries and the following events: Event Paleozoic-Mesozoic boundary First crocodiles Rifting that eventually led to opening of the Atlantic Ocean begins (Triassic/Jurassic rift basins- local examples are Newark and Hartford Basins, these are the sources of "brownstone" building material) Palisade Sill emplaced (CAMP)- this is approximately the Triassic-Jurassic boundary Early Mammals (shrew-like, rodents) North America separates from Africa- beginning of North Atlantic Ocean First bird, Archaeopteryx Earliest flowering plant, Archaefructus South America separates from Africa- beginning of South Atlantic Tyrannosaurus Rex and Velociraptors roam Extinction of the dinosaurs and outpouring of the Deccan Traps basalt (MesozoicCenozoic boundary) Time in millions of years before present 251 240 220 200 200 190 155 130 100 70 65 Group 4: You have been assigned the Cenozoic. Please plot the Epoch boundaries and the following events: Event Mesozoic-Cenozoic boundary First Primates Crocodiles in Canadian Arctic First horses India begins to collide with Asia Antarctic Circumpolar Current forms Antarctic Ice caps form First evidence of North Atlantic Deep Water forming Alps form (restriction of Tethyan seaway, formation of Mediterranean Sea) Panama passage closes, linking of North and South America Early hominids (Australopithecus) Initiation of major Northern Hemisphere glaciation Beginning of prominent 100 ky glacial cycles First use of fire Last time glaciers covered New York City (last glacial maximum or LGM, (pCO2 180 ppmv) Last major cold snap in Greenland Modern man Medieval Warm Period (Vikings settle Greenland) Little Ice Age (Viking settlements collapse) Death of King Tutankhamen Beginning of Industrial revolution (pCO2 280 ppmv) Today (pCO2 380 ppmv) Time in millions of years before present 65 60 55 55 40 35 35 35 20 4 3 2.7 0.7 0.5 0.018 0.013 0.01 0.0007-0.0010 0.0035-0.0015 0.003 0.0001 0