Precambrian
4.6 billion –
570 million years ago
(mya)
Phanerozoic
570 mya –
present
Paleozoic
570 million y.a. – 245 mya
Cambrian 570
– 505 mya
Ordovician
505 – 438 mya
Major Events in the Geologic and Cultural History of Vermont
For use with Landscape Change Project Lesson 2
Compiled by Jens Hilke
7/03
3.5 billion years ago
Cyanobacteria found in fossil record
Invertebrates found in fossil record end of Precambrian
1.5 billion ya Grenville supercontinent existed
700mya Grenville supercontinent begins to breakup
550mya
500mya
450 mya
First fish appear in record (Trilobites, Brachiopods, Crinoids)
Iapetus Ocean has formed (VT underwater)
Champlain Valley Sediments (Dunham dolomite, Monkton quartzite are being deposited underwater on continental shelf )
First Land animals (millipedes)
Taconic Orogeny -Green Mountains are forming under Iapetus as plates have reversed themselves. Proto America collides with
Iapetus plate
Green Mountains pushed up out of water as collision continues
Devonian 408
– 360 mya
400 mya
First amphibians
Acadian Orogeny begins as Proto European plate collides with chain of island arcs from Taconic orogeny. White Mountains begin formation
Carboniferous
360 – 286 mya
Mississippian
360 -320 mya
320 mya
Lush forests covered the Earth (later compressed by weight of rock over top to form present-day coal deposits
Alleghanian Orogeny as Proto European plate collides with Proto
American plate. 320 mya Pangea is formed
Major Events in the Geologic and Cultural
History of Vermont
Landscape Change Program

Permian 286 –
245 mya
Pennsylvanian
320 -286 mya
Amphibians were dominant life form
First reptiles appear
First Coniferous plants
Extinction of trilobites
Mesozoic
245 –
66.4 mya
Triassic 245 -
208 mya
Jurassic 208
– 144mya
200 mya
Breakup of Pangea
Champlain Valley is formed (a partial rift valley) as plates split up
First Mammals
Conifers and cycads are common
Atlantic Ocean begins to form
Dinosaurs dominant
First birds
Pangea splits up as plates again reverse themselves
Flowering plants found in fossil record
Cenozoic
66.4 mya
Cretaceous
144 – 66.4 mya
Tertiary 66.4
– 1.6 mya
Major Events in the Geologic and Cultural
History of Vermont
Landscape Change Program

- present Quartenary
1.6 mya - present
1 million ya -New and sudden uplift of ancient Adirondacks
20,000 years ago
-Wisconsin Glaciation at its maximum. Ice covered Canada and U.S. down to Long Island, NY.
15,000 ya
13,000 ya
12,000 ya
- Massachusetts was Ice free as glacier retreated
-When Ice is partially covering Vermont, Glacial lake
Vermont and Glacial Lake Hitchcock are formed behind receding glacier
-Vermont Ice free by 12,000 ya
11,000 ya
10,000 ya
10,000 ya
-Champlain Sea is formed as water rushes in from St. Lawrence
(11,000 ya Champlain Sea at its maximum)
-Isostatic rebound closes the connection with the St. Lawrence and Lake Champlain drains to the south
-Tree species (spruce and fir) begin to invade post-glacial landscape
-Massive extinction of wooly mammoth, mastadon, American
Lion, giant ground sloth, sabertooth, dire wolf, giant beaver. (Overkill or Overchill?)
Paleoindians (in Vermont as early as 10,000 years ago) hunted tundra and open woodland/fished in Champlain Sea/may have helped cause extinction of large mammals from N.
America/lived in small groups and moved constantly
4,500 ya pre-4000 ya
-Forests begin to look like they did when colonists arrived
Archaic (inhabited Vermont pre-4000 years ago) hunted, fished, and gathered from the new forested landscape/liked to live around rivers/larger groups than
Paleoindians/moved with the seasons post-4000 ya Woodland (inhabited Vermont
Major Events in the Geologic and Cultural
History of Vermont
Landscape Change Program

900 ya
600 ya
403 ya post-4000 years ago) hunted, fished, and gathered and eventually agriculture/pottery and bows & arrows/large villages/agriculture led to permanent villages earliest agriculture in Connecticut River Valley earliest agriculture in Champlain Valley
Abenaki (in Vermont by 1600 when European explores visited) hunting, gathering and agriculture/moved with the seasons/stored large amounts of food for the winter/several different bands of Abenaki in Vermont
403 ya 1600 French explorer Samuel de Champlain visits Vermont
387-370 ya 1616-1633 European diseases kill 90% of Abenaki population in
New England
361 – 240 ya 1642-1763 French and British come to Vermont/Abenaki tribes trade furs with them
240 ya 1763 large numbers of British moved to Vermont after the
British-French signed Treaty of Paris to end war
243-212 ya 1760-1791 New York, New Hampshire, and Massachusettes fight over Vermont territory until it becomes a state in 1791
203 ya 1800 over 150,000 colonists in Vermont
NOTE: Geologic dates are from Klyza and Trombulak The Story of Vermont (Citation below) These dates change a bit depending on who you read.
Check these books for more information:
Albers, Jan, 2000, Hands on the Lan d, a History of the Vermont Landscape, The MIT Press: Cambridge, Massachusetts, 351 p.
Major Events in the Geologic and Cultural
History of Vermont
Landscape Change Program

Klyza, C.M. and Trombulak, S., 1999, The Story of Vermont: A Natural and Cultural Histor y, University Press of New England:
Hanover and London, 240 p.
Major Events in the Geologic and Cultural
History of Vermont
Landscape Change Program