U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Eagle River porphyry*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Eagle basin
Publication:

Tweto, Ogden, 1951, Form and structure of sills near Pando, Colorado: Geological Society of America Bulletin, v. 62, no. 5, p. 507-532.


Summary:

Is a quartz monzonite porphyry in Eagle basin composed of abundant phenocrysts of feldspars, quartz, and biotite in a gray or greenish crystalline matrix. Is later than Lincoln porphyry. Was formerly included in Lincoln porphyry. Assigned to early Tertiary.

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


Map showing publication footprint
  • Usage in publication:
    • Eagle River Porphyry*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Eagle basin
Publication:

Tweto, Ogden, 1974, Geologic map and sections of the Holy Cross quadrangle, Eagle, Lake, Pitkin, and Summit Counties, Colorado: U.S. Geological Survey Miscellaneous Investigations Series Map, I-830, 2 sheets, scale 1:24,000


Summary:

Occurs principally as sills in area between East Fork of Eagle River and East Tennessee Creek, Eagle Co., CO in Eagle basin. Is assigned to Paleocene?.

Source: GNU records (USGS DDS-6; Denver 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 ([ ]).

Accessibility FOIA Privacy Policies and Notices

USA Gov U.S. Department of the Interior | U.S. Geological Survey
Supported by the National Cooperative Geologic Mapping Program
Page Contact Information: Personnel
Page Last Modified: Thu 04 Apr 2024 03:55:45 PM MDT