Editing Laurasia (section)

==Terminology and origin of the concept==
Laurentia, the [[Paleozoic|Palaeozoic]] [[Craton|core]] of North America and continental fragments that now make up part of Europe, collided with [[Baltica]] and [[Avalonia]] in the [[Caledonian orogeny]] from c. 430–420&nbsp;Mya to form Laurussia. In the Late [[Carboniferous]], Laurussia and Gondwana collided and formed Pangaea. [[Siberia (continent)|Siberia]] and [[Kazakhstania]] finally collided with Baltica in the Late Permian to form Laurasia.<ref>{{Harvnb|Torsvik|Van der Voo|Preeden|Mac Niocaill|2012|loc=From Laurentia to Laurussia and Laurasia: Overview, p. 6}}</ref> A series of continental blocks that now form East Asia and Southeast Asia were later added to Laurasia.

In 1904–1909, Austrian geologist [[Eduard Suess]] proposed that the continents in the [[Southern Hemisphere]] were once merged into a larger continent called Gondwana. In 1915, German meteorologist [[Alfred Wegener]] proposed the existence of a supercontinent that he called Pangaea. In 1937, South African geologist [[Alexander du Toit]] proposed that Pangaea was divided into two larger landmasses, Laurasia in the Northern Hemisphere and Gondwana in the Southern Hemisphere, separated by the Tethys Ocean.<ref name="Meert-2012">{{Harvnb|Meert|2012|pp=991–992}}</ref>

"Laurussia" was defined by Swiss geologist [[Peter Ziegler]] in 1988 as the merger between Laurentia and Baltica along the northern Caledonian suture.  The "Old Red Continent" is an informal name often used for the Silurian-Carboniferous deposits in the central landmass of Laurussia.<ref>{{Harvnb|Ziegler|1988|loc=Abstract}}</ref>

Several earlier supercontinents proposed and debated in the 1990s and later (e.g. Rodinia, Nuna, Nena) included earlier connections between Laurentia, Baltica, Siberia.<ref name="Meert-2012" /> These original connections apparently survived through one and possibly even two [[Wilson Cycle]]s, though their intermittent duration and recurrent fit is debated.<ref>{{Harvnb|Bleeker|2003|p=108}}</ref>