TY - DATA T1 - Chapter 5 Palaeogeographic and tectonic evolution of the Arctic region during the Palaeozoic PY - 2016/06/21 AU - Lawrence A. Lawver AU - Lisa M. Gahagan AU - Ian Norton UR - https://geolsoc.figshare.com/articles/media/Chapter_5_Palaeogeographic_and_tectonic_evolution_of_the_Arctic_region_during_the_Palaeozoic/3452912 DO - 10.6084/m9.figshare.3452912 L4 - https://ndownloader.figshare.com/files/5420897 KW - 6000 km KW - Gondwana motion KW - tectonic evolution KW - 406 Ma KW - palaeomagnetic poles KW - year steps KW - tectonic blocks KW - Iapetus Ocean KW - Chapter 5 Palaeogeographic KW - animation KW - future Arctic continents KW - palaeomagnetic pole values KW - 250 Ma KW - Palaeozoic motion KW - day plate motion KW - Middle Cambrian KW - Silurian KW - Arctic region KW - Arctic orogenies KW - Scandian Caledonian KW - Arctic continents KW - Geology N2 - The Palaeozoic motion of the future Arctic continents is presented in the animation found in the accompanying CD-ROM. The animation shows snapshots of the motion of the tectonic blocks from 550 to 250 Ma in 3 million year steps. The locations of the blocks are controlled mainly by palaeomagnetic pole values for the blocks tied to known geological events, particularly the three main Arctic orogenies: the Scandian Caledonian which began in the Silurian, the Ellesmerian in the Late Devonian and the Uralian that began in the Late Pennsylvanian. Perhaps the most significant observation to come out of the animation is that the future Arctic continents were never very far from one another during the Palaeozoic. The maximum distance from Baltica to Laurentia may have reached 6000 km during the Middle Cambrian but the Arctic continents all surrounded the same eastern Iapetus Ocean and, by Silurian, they were quite close. Reliance on the ‘Y-loop’ palaeomagnetic data causes extremely rapid motion of Gondwana during the Silurian. Consequently the ‘X-path’ for that period is used. The palaeomagnetic poles for 422 and 406 Ma have been eliminated so that Gondwana motion is within the bounds of present day plate motion. ER -