Laurasia

Laurasia was the northern part of a huge land called Pangaea. This was about 335 to 175 million years ago (Mya). The southern part was called Gondwana.

Laurasia started to move away from Gondwana about 215 to 175 Mya. This happened in the late Triassic period. After separating, Laurasia moved north and later broke apart when the North Atlantic Ocean began to open around 56 million years ago.

The name Laurasia comes from two places: Laurentia and Eurasia. Many smaller pieces of land, called terranes, came together to form Laurasia. These included places like Avalonia, Baltica, and others. Later, Kazakhstania and Siberia also joined Laurasia. This landmass was very important for Earth's continents and the life that lived there.

Terminology and origin of the concept

Laurentia, the core of North America and parts of Europe, joined with Baltica and Avalonia to form Laurussia. Later, Laurussia joined with Gondwana to create the supercontinent Pangaea. Siberia and Kazakhstania also joined, forming Laurasia.

The idea of Laurasia was suggested by scientists over many years. In 1904–1909, Eduard Suess talked about Gondwana. In 1915, Alfred Wegener suggested Pangaea. In 1937, Alexander du Toit split Pangaea into Laurasia and Gondwana. The term "Laurussia" was defined in 1988 by Peter Ziegler.

Proto-Laurasia

Main article: Rodinia

Main article: Pannotia

Laurentia and Baltica joined together to form a landmass called Proto-Laurasia. This happened as part of a huge supercontinent named Columbia, which existed around 2,100 to 1,800 million years ago. This early landmass included parts of many continents we know today.

Later, these lands became part of another supercontinent called Rodinia. Rodinia formed about 1,260 to 900 million years ago. It eventually broke apart, creating new oceans and moving continents to where they are now. During this time, Laurentia moved toward the Equator, while Baltica stayed closer to the south.

Euramerica/Laurussia

Main article: Pangaea

Laurentia stayed near the Equator during the early Palaeozoic era, far from Baltica because of the wide Iapetus Ocean. Over time, changes in ocean movements created a new ocean called the Rheic Ocean. During this time, land pieces called Avalonia, Carolinia, and Armorica moved away from Gondwana.

Eventually, Avalonia moved toward Baltica and they joined together near Laurentia, forming a new landmass called Laurussia, also known as Euramerica. This continent covered a huge area and had many different landscapes. During the Devonian period, many sea creatures lived in the shallow waters around Laurussia, and the first tetrapods, or four-legged animals, evolved from fish.

Later, Laurussia joined with Gondwana to form the supercontinent Pangaea. This huge landmass experienced many changes in climate and plant life over millions of years, from tropical rainforests to drier areas.

Laurasia

During the Carboniferous to Permian periods, Siberia, Kazakhstania, and Baltica came together to form Laurasia. This landmass was part of a bigger supercontinent called Pangaea. Pangaea started to break apart about 215 to 175 million years ago.

Laurasia was the northern part of Pangaea, and Gondwana was the southern part.

As Pangaea split, Laurasia moved further north. The opening of the North Atlantic Ocean about 56 million years ago made Laurasia break apart into the continents we have today. While Laurasia existed, it was home to many plants and animals, like early pine trees and different dinosaurs. The movement of Earth's plates changed the land and affected the weather and life there.