Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Earth Systems 3209 Unit: 4 The Forces Within Earth Reference: Chapters 4, 15, 16, 19; Appendix A & B

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Geology of Newfoundland Unit 4: Topic 2.8 Focus on...  describing the geologic layout of the island of Newfoundland.  Core STSE – “The Geology of Newfoundland and Labrador”

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador  The Geological Formation of Newfoundland  About 500 hundred million years ago, the central portion of North America was under a warm tropical sea called the Iapetus Ocean. Europe, Africa and North America bordered this body of water. North American Plate African Plate Iapetus Ocean Plate Tectonics and Newfoundland

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador  The Geological Formation of Newfoundland  Over the next 150 million years (350 million years ago), forces within Earth’s mantle slowly carried these continents on a collision course. As the continents drifted together and collided, the ocean floor (a volcanic island arc) was squeezed and then pushed upward to form the Appalachian Mountains. Plate Tectonics and Newfoundland North American Plate African Plate Iapetus Ocean

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador  The Geological Formation of Newfoundland  The remains of this mountain range now exists throughout central and western Newfoundland and is the northern most part of the Appalachians in North America. This range, continues through most of the British Isles and into Norway. Plate Tectonics and Newfoundland

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Ophiolite Complex Tablelands  The Geological Formation of Newfoundland  An area called the Tablelands in Gros Morne National Park has rocks that were once part of Earth’s mantle but were pushed on top of Earth’s crust during the collision of the continents 350 million years ago. These sightings called Ophiolite complexes, represents an ocean floor profile resting on land and are rarely seen on Earth’s surface. Plate Tectonics and Newfoundland

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador North Americam Plate African Plate New Divergent Boundary  The Geological Formation of Newfoundland  225 million years ago, the forces in Earth’s mantle that brought the continents together reversed and slowly began to pull them apart. The divergent boundary responsible for the shifting of the plates rifted within the African plate and caused the plates to drift apart, leaving a small section of the African plate behind. Plate Tectonics and Newfoundland

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador North Americam Plate African Plate New Divergent Boundary African Plate Left Behind Plate Tectonics and Newfoundland  The Geological Formation of Newfoundland  During this process a small bit of Africa got left behind! When you stand on Signal Hill in St. John’s, you are standing on rocks that are identical to ones in the country of Morocco in Northern Africa! The Eastern part of Newfoundland was once a part of the African plate.

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Western Zone Eastern Zone Central Mobile Belt  The Geological Layout of Newfoundland  Western (Humber) Zone:  Has been a part of the North American plate for at least the last billion years.  Central (Zone) Mobile Belt:  Remnants of volcanic island arcs and the ancient Iapetus ocean floor.  Eastern (Avalon) Zone:  Once part of the African plate which remained attached as Pangaea split 200 million years ago. Plate Tectonics and Newfoundland

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Eastern (Avalon) Platform Western (Humber) Platform Site of ophiolite sequence Central Mobile Belt Plate Tectonics and Newfoundland  The Geology of Newfoundland Labrador

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Example 1: Which area of the island of Newfoundland is composed of rocks similar to an ancient ocean floor? (A)Eastern(B)Central (C)Southern(D)Western

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Example 2: When the Proto-Atlantic Ocean closed many years ago, which mountain chain was created on the East coast of North America? (A)Andes Mountains (B)Appalachian Mountains (C)Himalaya Mountains (D)Rocky Mountains

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Your Turn... Take the time and complete the following questions... (Solutions to follow) Questions: Use the diagram and your knowledge of the theory of Plate Tectonics to explain how the three geologic zones of the island portion of Newfoundland and Labrador were formed. A BC

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Solutions... Question: Use the diagram and your knowledge of the theory of Plate Tectonics to explain how the three geologic zones of the island portion of Newfoundland and Labrador were formed. Answer: It is thought that the geology of Island Newfoundland resulted long ago when the Iapetus Ocean was closing. The North American plate collided with the African plate and as a result a portion of the Iapetus Ocean floor was sandwiched in between. Zone “A” is referred to as the Western (Humber) Zone and was part of the North American plate. Zone “C” is referred to as the Eastern (Avalon) zone and is thought to part of the African plate. Zone “B” is referred to as the Central Mobile Belt and is thought to be once part of the ancient Iapetus Ocean. A BC

Copyright © 2014 All rights reserved, Government of Newfoundland and Labrador Summary... Overview of Points covered: Newfoundland is divided into THREE geologic zones: 1)Western (Humber) Zone 2)Central (Zone) Mobile Belt 3)Eastern (Avalon) Zone Note: Newfoundland formed as a result of plate tectonic activity over the past 500 million years. This activity formed the Appalachian Mountains and left a part of the African Plate behind as part of Eastern Newfoundland.