|This is a satellite image of northern and western Alaska, Bering Strait, and the Chukotka Peninsula of Russia. – NASA Worldview satellite image, https://earthdata.nasa.gov/labs/worldview/.|
The evolution and origin of Earth’s Arctic realm and the nature, location, and age of its major tectonic boundaries remain subjects of considerable uncertainty. This new compilation of studies from The Geological Society of America demonstrates the power of modern research tools to penetrate the effects of orogenesis and reconstruct the area’s pre-deformational tectonic and paleogeographic history.
The largest piece of continental crust that plays a role in Arctic tectonics is the Arctic Alaska-Chukotka terrane or microplate. This microplate includes northern Alaska and northeastern-most Russia, along with the adjacent continental shelves. Because of its size, understanding its origin and movements during the Paleozoic and Mesozoic are critical components of tectonic and paleogeographic models.
This new GSA Special Paper, edited by Julie A. Dumoulin and Allison B. Till of the U.S. Geological Survey, examines the Arctic Alaska-Chukotka microplate from the Late Proterozoic (about 240 million years ago) to the Devonian (from 360 to 410 million years ago), and includes the first compelling evidence for a rift event that may have detached the Arctic Alaska-Chukotka microplate from the Timanide margin of Baltica.