Northern Pacific orogens: A collage of terranes and history of its formation

The orogens of the northern Pacific framing are made by a collage of terran es that are fragments of island arcs, active and passive continental margin s, accretionary complexes, and cratons. The formation of Mesozoic and Cenoz oic orogens was controlled by convergent movements of oceanic (Paleopacific ) and continental (North-American and North-Asian or Siberian) plates accom panied by rifting and opening and closure of small oceanic basins at the ba ck of active continental margins and island arcs. Systems of island arcs an d active continental margins have been distinguished, which stretch for tho usands of kilometers and are common For North America and northeastern Asia , like those now existing along the periphery of the Pacific. Disintegratio n of large tectonic units (island arcs, etc.) was either synaccretional or postaccretional, the latter chiefly resulted from large-scale movements on wrench faults striking roughly parallel to the continent-ocean boundary. The tectonic evolution of the northern Pacific framing and formation of oro gens are illustrated by a set of palinspastic maps compiled on the basis of an earlier terrane analysis and critically reviewed paleomagnetic and pale obiogeographic published data for Russian Far East, Alaska, Canadian Cordil leras, and island of Hokkaido (Japan), completed with studies of terrane-re lated overlap and suturing complexes.