Scientists have recently identified a new microcontinent submerged between Canada and Greenland.
This newly recognized landmass called the Davis Strait proto-microcontinent is a thicker-than-normal fragment of continental crust located in the ocean (via Phys.org).
This geological discovery was detailed in a recent study published in Gondwana Research by researchers from the University of Derby and Uppsala University.
(Photo : Greg Rosenke on Unsplash) Scientists discovered a new submerged microcontinent, the Davis Strait proto-microcontinent, between Canada and Greenland, formed by shifting tectonic plates millions of years ago.
Moving Tectonic Plates
Earth's surface is composed of massive slabs of rock known as tectonic plates. These plates are in constant, albeit slow, motion due to the convection processes occurring in the mantle.
This movement is the driving force behind the planet's shifting continents, causing earthquakes, volcanic eruptions, and mountain formations, particularly at plate boundaries.
One of these plate boundaries lies between Canada and Greenland, forming the Davis Strait seaway, which connects the Labrador Sea and Baffin Bay.
The tectonic evolution of the Davis Strait dates back to approximately 33 to 61 million years ago during the Paleogene period. It was during this time that an unusually thick piece of continental crust formed in the ocean, now recognized as the Davis Strait proto-microcontinent.
Doctoral researcher Luke Longley, Dr. Jordan Phethean from the University of Derby, and Dr. Christian Schiffer from Uppsala University spearheaded the research.
They reconstructed the plate tectonic movements over 30 million years which led to the formation of the proto-microcontinent.
The team focused on the Davis Strait due to its well-defined changes in plate motion, making it an ideal natural laboratory for studying microcontinent formation.
Dr. Phethean explains that the well-defined changes in plate motion occurring in the Labrador Sea and Baffin Bay, which have relatively limited external complications affecting them, make this area an ideal natural laboratory for studying microcontinent formation.
The Tectonic Timeline
Initial rifting between Canada and Greenland began around 118 million years ago during the Lower Cretaceous period, a time when dinosaurs still roamed. Seafloor spreading commenced in the Labrador Sea and Baffin Bay approximately 61 million years ago.
The critical period for the formation of the Davis Strait proto-microcontinent occurred between 49 and 58 million years ago when the orientation of seafloor spreading between Canada and Greenland shifted, resulting in the rifting off of the proto-microcontinent.
By around 33 million years ago, ocean spreading ceased as Greenland collided with Ellesmere Island, subsequently joining the North American plate.
The Davis Strait proto-microcontinent was identified based on crustal thicknesses, with the microcontinent appearing in the range of 19 to 24 kilometers thick, surrounded by two narrow bands of thinner continental crust that separate it from mainland Greenland and Baffin Island.
The research team's findings have broader implications for understanding microcontinent formation worldwide.