Post on 19-Dec-2015
EARLY PALEOZOIC EVENTSCAMBRIAN PALEOGEOGRAPHY
Development of a shallow epeiric or epicontinental sea
Continent situated on the equator, so waters most likely warm
Significant carbonate deposits accumulate
Deep water sediments (shales) are accumulating on margins
EARLY PALEOZOIC EVENTSCAMBRIAN PALEOGEOGRAPHY
Cambrian stromatolitesPetrified Sea GardensSaratoga Springs, NY
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Ordovician named after the Ordovices, an early Celtic tribe named by Charles Lapworth as a compromise in 1879
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Ouachita Terrane
Broken off Laurentia
Forms a microcontinent
Will collide with South America
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Taconic Orogenic Belt
Begins development along margins of Laurentia and Baltica
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Global sea level is highGondwanaland moving towards South Pole
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
Gondwanaland moving towards South PoleLeads to glaciation at the end of Ordovician
EARLY PALEOZOIC EVENTS
ORDOVICIAN PALEOGEOGRAPHYSea level high
Canadian Shield being covered by sediments
Shallow water carbonates in the mid-continent regions with mudcracks and stromatolites in Early Ordovician
EARLY PALEOZOIC EVENTS
ORDOVICIAN PALEOGEOGRAPHYCarbonate deposition ended in the Middle Ordovician
Region was downwarped
Caused by closing of the Iapetus Ocean along a subduction zone
Prior to the Taconic orogeny, the "east" coast of what is now the United States was located near the Hudson River valley, Philadelphia, Washington, DC and extended to western South Carolina.
The Taconic Orogeny added land to Proto North America that is now the western portions of New England and the Canadian Maritime provinces. This collision added land and raised mountains southward through northern New Jersey, south-eastern Pennsylvania, Virginia and North Carolina.
Occurred approximately 460-480 myBP
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
The Taconic island chain began to collide with Proto North America about 470 to 450 million years ago
The energy of ongoing impacts was still raising mountains from Canada to Virginia 430 million years ago.
The Iapetus Ocean, which had been the shoreline for Proto North America, is closing as Western and Eastern Avalonia, following behind the Taconic arc, are heading for collision with the recently-extended coast of Proto North America.
EARLY PALEOZOIC EVENTSORDOVICIAN PALEOGEOGRAPHY
TAC
Taconic Island Chain
EAV
Eastern Avalon Terrane
WAV
Western Avalon Terrane