TABLE

TIME

GENERAL

PLATES

ILLINOIS

15-20 BY Big Bang
4.6 BY Age of moon rocks, meteorites
3.8 BY Oldest earth rocks
3.0 BY Stromatolites
1.7 BY Supercontinent
1.5 BY

Cascade

volcanics

1.2 BY Grenville Orogeny Suturing of SE N. Am & Gondwana
1.15 BY Formation of Gulf of Mexico Rifting Reelfoot Rift Aulacogen
1-0.57 BY Rifting - N.Am & Europe Emergent
542 MYBP Cambrian 5 separate continents

Emergent, then shallow sandy seas

490 MY Ordovician

Rise of Appalachians; widespread seas Collision of Gondwana & N.Am begins Shallow limestone seas; sands wash in
425 MY Silurian Widespread seas Continued collision Extensive reefs in tropical seas
405MY Devonian Widespread seas Rise of Appalachians; suturing of plates Deep stagnant basin; Black shale
355 MY Mississippian Widespread seas and limestone deposits Continued suturing Widespread seas; deposit of lead, zinc
300 MY Pennsylvanian East coastal sands, coal forests, swamps and deltas Formation of Pangaea Coastal Coal forest; Deltas, swamps
280 MY Permian Seas surround Pangaea Pangaea Emergent; no record
230-65MY Reefs in Tx; Glaciers in Gondwana Break-up of Pangaea Fluorite Fm; meteorite impact, Hicks dome
65-1.8 MY Glaciation; rise of Himalayas Separate continents continue to move Delta sediments
1.8-0.1 MY Slow rise of Himalayas Continents move; ring of fire Glaciation, Great Lakes, exhuming of canyons

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