Potassium-argon ages of basement rocks from Saint George Island, Alaska
Potassium-argon ages from basement granitic rocks that intrude serpentinized peridotite on St. George Island, Alaska, range from 50 to 57 million years, with an initial argon isochron age. interpreted as a minimum figure, of 52 ± 2 m.y. The age of the granitic rocks and their association with serpentinized peridotite near the continental margin, which apparently marks the site of a Mesozoic subduction zone, suggest that the position of the subduction zone shifted southward to the Aleutian Trench in early Tertiary time.
|Publication Subtype||Journal Article|
|Title||Potassium-argon ages of basement rocks from Saint George Island, Alaska|
|Series title||Journal of Research of the U.S. Geological Survey|
|Publisher||U.S. Geological Survey|
|Other Geospatial||Saint George Island|
|Google Analytic Metrics||Metrics page|