Anybody who loves nature, mountains and the wonders of the natural world can appreciate this unique National Park, it is just simply beautiful and diverse! However, for those who know what to look for (geologically speaking) it is a mine of knowledge with classic “textbook” examples of earth forming processes including plate tectonics and glaciation, all within a relatively small and accessible geographic region. In fact, this area's ability to illustrate the process of continental drift along North Americas eastern coast has contributed significantly to the current understanding of plate tectonics and the geological evolution of mountain belts. This fascinating geological representation within Gros Morne National Park is one of the main reasons that it is also designated as a World Heritage Site by UNESCO (the United Nations Education, Scientific and Cultural Organization). 

Gros Morne is situated on the west coast of the Newfoundland Island (colloquially known as “the rock”). In the southern area of the park lays the Tablelands of Gros Morne. While the surrounding area is lush and green, the tablelands are marked by a distinctive rusted-red landscape that appears barren in comparison. The main contributing factor for this? GEOLOGY 

Picture 1: Trail to Gros Morne Tablelands 

In the short version, the Tablelands marks a rare phenomenon, known as an Ophiolite complex, where earths iron rich mantle was thrusted upwards by the collision of tectonic plates millions of years ago.  

In the less condensed version, the Ophiolite complex at Gros Morne occurred when the collision of 2 oceanic plates resulted in one plate being pushed up over the other in the ancient Iapetus Ocean. As the plates continued to come together, the magma from Earth's mantle welled upwards to form peridotite, dunite and gabbro representing the boundary between the ancient oceanic crust and the upper mantle known as the Mohorovicic Discontinuity.  As the Iapetus Ocean closed, still hot ophiolite (a thrust sheet of oceanic crust and upper mantle rocks) was pushed over the crustal ocean plate, across the continental margin and onto the continental crust creating the Tablelands we see today.  

The geology of the Tablelands dictates the ecology of this area as peridotite is a poor host for plants. But never fear, there are still some hardy dwellers in the area such as pitcher plants that contribute to this unique and almost alien eco-zone.   

Picture 2: Pitcher plants at Gros Morne 

Fun Fact: 

The word ‘Ophiolite’, Greek in origin, translates as snakestone and is named as such for the snakeskin like patterns on the peridotite serpentine rocks of this region.  

Picture 3: Close up of peridotite serpentine rocks.

The tablelands only touch on one geological (yet fascinating) piece of Gros Morne’s history. There are more stories held within these stones, ranging from the formation of the long-range mountains during the Precambrian era to more recent glaciation periods. Certainly, one blog could not capture it all! From the eroded Appalachian mountain chain of the Long Range Mountains, the diabase dykes and fjords of the Western Brook Pond, to the Mohorovicic Discontinuity of the tablelands, Gros Morne is a place to marvel for any plain ol’ nature lover, geologist and geomorphologist alike.  

Till next time, your travel agent and nature enthusiast - Sarah 

Read more at: 

UNESCO

Parks Canada