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  • Usage in publication:
    • Boulder Creek Volcanics
  • Modifications:
    • Named
  • Dominant lithology:
    • Basalt
  • AAPG geologic province:
    • Alaska Southern region
Publication:

Stout, J.H., 1976, Geology of the Eureka Creek area, east-central Alaska Range: Alaska Division of Geological and Geophysical Surveys Geologic Report, no. 46, 32 p.


Summary:

Named for Boulder Creek. Type locality designated as low mountains north of Boulder Creek and Sevenmile (Boulder) Lake, Eureka Creek area, Mount Hayes A-5 and B-5 quads, AK. Is upper unit of three in Amphitheater Group. Occupies core of east-west Amphitheater syncline. Consists of gray to green basalt and amygdaloidal basalt. Is 5,600 m thick. Overlies Tangle Lakes Formation (new) (Amphitheater Group); upper contact not exposed (top eroded); intruded by gabbro dikes related to Fish Lake Complex. Is Late Triassic age.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

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