What is Iapetus Ocean?
[[Image:Positions_of_ancient_continents,_550_million_years_ago.jpg|thumb|right|upright=1.35|Reconstruction of how the Iapetus Ocean and surrounding continents might have been arranged during the late [[Ediacaran]] [[period (geology)|period]]]] [[File:Iapetus fossil evidence EN.svg|thumb|280px|Position of the continents after the [[Caledonian orogeny]] ([[Devonian]] to [[Permian]] times). Differences in fossil faunas on both sides of the red line (the '''Iapetus Suture''') are evidence for the existence of an ocean between the two sides in the time before the continents were joined in the [[supercontinent]] [[Pangaea]].<ref>Figure based on Windley (1996) and Ziegler (1990)</ref>]] [[File:Geological fault at Niarbyl - geograph.org.uk - 107854.jpg|thumb|right|280px|Geological fault at Niarbyl, [[Isle of Man]]. The narrow white diagonal line near centre of picture is the only remaining visible sign of the Iapetus Ocean]] The '''Iapetus Ocean''' existed in the [[Neoproterozoic]] and [[Palaeozoic]] [[era]]s (between 600 and 400 million years ago). The ocean was in the [[southern hemisphere]], between three paleocontinents. The ocean disappeared when these three continents joined to form one big landmass.<ref>The three palaeocontinents collided, producing three mountain-building events: the [[Caledonian orogeny|Caledonian]], [[Taconic orogeny|Taconic]] and [[Acadian orogeny|Acadian]] [[orogeny|orogenies]].</ref> That large continent has been given various names, such as [[Laurussia]] or the [[Old Red Sandstone]] continent. Probably the best name is [[Euramerica]], because basically it was American and Europe stuck together. The Iapetus Ocean was between continental masses that would at a much later time roughly form the opposite shores of the [[Atlantic Ocean]]. It was a kind of precursor of the Atlantic.<ref>The name Iapetus was first used by Harland & Gayer (1972), before that the ocean was referred to as the ''Proto-Atlantic''</ref> At the start of the 19<sup>th</sup> century, American paleontologist [[Charles Doo