USGS Professional Paper 1697 - Alaska Resources Library

Table 2—Continued
Unit(s) and Correlations.
Age
Tectonic Environment(s)
Mainitskiy Island Arc
Tectonic Linkages.
Comments
Mainitskiy terrane.
Late Jurassic to mid-Cretaceous.
Island arc Axial part of arc.
Alkatvaam.
Accretionary wedge Linked to Mainitskiy arc. Remnants of subduction
Late Triassic to Paleocene.
Uyandina island arc
of Ancestral Pacifi c oceanic plate.
Uyandina-Yasachnaya volcanic belt.
Late Jurassic.
Island arc Axial part of arc.
Garbyn’ya, Debin, and Chursky Range ophio- Ophiolite Linked to Uyandina arc. Remnants of subduction of
lites.
Unknown.
Oimyakon oceanic plate.
Oloy and Svyatov Nos Continental-Margin Arcs
Oloy and Svyatov Nos Arcs volcanic belts.
Late Jurassic.
Continental-margin arc Axial part of arc.
South Anyui terrane.
Subduction zone Linked to Oloy and Svyatov Nos arcs. Remnants of
Late Jurassic and Early Cretaceous.
Alazeya Island Arc
subduction of South Anyui oceanic plate.
Alazeya, Khetachan, and Oloy terranes.
Late Paleozoic to Early Jurassic.
Island arc Axial part of arc.
Aluchin terrane.
Subduction zone Linked to Alazeya arc. Remnant of subduction of
Late Paleozoic to Early Jurassic.
Ancestral Pacifi c oceanic plate.
Nutesyn Continental-Margin Arc
Nutesyn terranes.
Mainly Late Jurassic to Early Cretaceous.
Continental-margin arc Axial part of arc.
Velmay terrane.
Subduction zone Linked to Nutesyn arc. Remnant of subduction of
Upper Triassic.
Koyukuk Island Arc
Angayucham oceanic plate.
Koyukuk, Nyac, and Togiak terranes.
Mainly Late Jurassic to Early Cretaceous.
Island arc Axial part of arc.
Angayucham and Goodnews terranes.
Subduction zone Linked to Koyukuk arc. Remnant of subduction of
Devonian to Early Jurassic.
Gravina Island Arc
Angayucham oceanic plate.
Kahiltna sedimentary and volcanic assemblage;
Gravina-Nutzotin-Gambier volcanic-plutonic-sedimentary
belt; Cadwaller, Methow,
Izee, and Wallowa island-arc and turbiditebasin
terranes; Spences Bridge volcanicplutonic
belt; Tahtsa-Three Sisters-Francois
Lake magmatic assemblage.
Juassic to mid-Cretaceous with minor Triassic
units.
Island arc and turbidite basin Axial part of arc.
Chugach (younger part, Valdez Group), Pacific
Rim, Bridge River, and Baker terranes.
Jurassic to Late Cretaceous.
Accretionary wedge and
subduction zone
Appendix 343
Linked to Gravina arc. Remnants of subduction of
Cache Creek oceanic plate.