New insights into North America’s ancient tectonic plates have been discovered by scientists. The evolution of the continent over the past 400 million years has been shaped by numerous tectonic events. The continent presently situates on the North American Plate, however it was not always this way. Recent studies have revealed new insights into the ancient tectonic plates that once influenced North America’s geography and history. Using computer models, scientists have discovered that a series of ancient arc volcanoes, known as the Kootenay Arc, once existed in what is now Western Canada.
Ancient Tectonic Plates in North America Yield New Insights
North America’s evolution over the past 400 million years has been shaped by numerous tectonic events. Currently, the continent sits on the North American Plate, however, it was not always this way. Recent studies have revealed new insights into the ancient tectonic plates that once influenced North America’s geography and history.
Plate Tectonics
Before diving into the ancient plates that once existed in North America, it’s important to understand the basics of plate tectonics. The Earth’s outer layer, or lithosphere, is fragmented into several plates that move relative to each other. The motion of these plates is propelled by convection currents in the mantle below.
This constant movement causes various tectonic features like mountains, volcanoes, and earthquakes. Additionally, it also allows for the creation and destruction of ancient tectonic plates. When plates collide, one plate is usually subducted, or pushed beneath, the other. When a plate is subducted, it melts into the mantle, causing new magma to rise to the surface and ultimately forming new landmasses.
Ancient Tectonic Plates in North America
North America has been a part of several tectonic plates throughout its history. One of the most significant ancient plates that influenced North America is the Iapetus Ocean plate. Around 600 million years ago, North America was situated on the eastern coast of the continent, facing towards the Iapetus Ocean. However, roughly 50 million years later, the Iapetus Ocean began to close, and the North American continent collided with another tectonic plate known as Avalonia. This collision altered North America’s geography and helped shape the Appalachian Mountains.
Another ancient tectonic plate that can be found in North America is the Farallon Plate. The Farallon Plate was one of the fastest-moving plates-known, moving at a rate of approximately eight inches per year. Around 250 million years ago, the Farallon Plate began to cause subduction beneath North America. Subduction led to the formation of numerous volcanoes in the western United States, including the Cascade Range of the Pacific Northwest, which includes Mount St. Helens and Mount Rainier.
New Insights
Recent studies have provided new insights into North America’s ancient tectonic plates. Using computer models, scientists have discovered that a series of ancient arc volcanoes, known as the Kootenay Arc, once existed in what is now Western Canada. The Kootenay Arc was formed as the result of subduction, where an ancient tectonic plate known as the Kula Plate was being pushed beneath North America around 200-190 million years ago. The subduction of the Kula Plate ultimately led to the formation of the Rocky Mountains.
FAQs
What is a tectonic plate?
A tectonic plate is the Earth’s outer layer or lithosphere broken into large pieces that move relative to each other.
What is subduction?
Subduction is the process where one tectonic plate is pushed beneath another, usually resulting in the formation of volcanoes or mountain ranges.
What is the Farallon Plate?
The Farallon Plate was a tectonic plate that existed in the Pacific Ocean and was responsible for subduction under North America’s western coast during the Mesozoic Era.
What is the Kootenay Arc?
The Kootenay Arc is a series of ancient arc volcanoes that once existed in Western Canada and was formed as the result of subduction from the Kula Plate.
How have ancient tectonic plates influenced North America’s geography and history?
Ancient tectonic plates have influenced North America’s geography and history by forming mountains, volcanoes, and shaping the continent into its current configuration.
