USGS/Cascades Volcano Observatory, Vancouver, Washington 

The Geologic Time Scale



 
Simplified Geologic Time Scale
Era Period or System Epoch or Series
Cenozoic
(66 million years ago - Present)
characterized by the emergence of the Himalayas (cooling, reduced CO2)
also, delineated by the K-T boundary


The Cascade Range began approximately 36 million years ago, with the major peaks appearing early to middle Pleistocene.


The Columbia River flood basalts erupted during middle Miocene, 17-12 million years ago.
Quaternary
(2 million years ago - Present)
characterizted by the appearence of humans
Holocene
(12,000 years ago - Present)
Pleistocene
(2 million - 12,000 years ago)
Tertiary
(66 - 2 million years ago)
Pliocene
(5 - 2 million years ago)
Miocene
(24 - 5 million years ago)
Oligocene
(37 - 24 million years ago)
Eocene
(58 - 37 million years ago)
Paleocene
(66 - 58 million years ago)
Mesozoic
(250 - 66 million years ago)


"The Age of Dinosaurs"
Cretaceous
(135 - 66 million years ago)
Late or Upper
Early or Lower
Jurassic
(205 - 135 million years ago)
Late or Upper
Middle
Early or Lower
Triassic
(250 - 205 million years ago)
Late or Upper
Middle
Early or Lower
Paleozoic
(570 - 250 million years ago)
Permian
(290 - 250 million years ago)
Late or Upper
Early or Lower
Carboniferous
(365 - 290 million years ago)
Pennsylvanian
(310 - 290 million years ago)
Late or Upper
Middle
Early or Lower
Mississippian
(365 - 310 million years ago)
Late or Upper
Early or Lower
Devonian
(400 - 365 million years ago)
Late or Upper
Middle
Early or Lower
Silurian
(425 - 400 million years ago)
Late or Upper
Middle
Early or Lower
Ordovician
(500 - 425 million years ago)
Late or Upper
Middle
Early or Lower
Cambrian
(570 - 500 million years ago)
Late or Upper
Middle
Early or Lower
Precambrian
(Beginning of earth - 570 million years ago)
 
Table by: Lyn Topinka, USGS/CVO, 1997,
Modified from:
  1. U.S.Geological Survey, Paleontology website: http://geology.er.usgs.gov/paleo/ 
  2. Swanson, et.al., 1989, Cenozoic vulcanism in the Cascade Range and Columbia Plateau, Southern Washington and Northermost Oregon, AGU Field Trip Guidebook T106 
  3. U.S.Army corps of Engineers, Portland District, and the U.S.Department of the Interior, U.S.Geological Survey, The Geologic History of the Columbia River Gorge: Information Broshure