- Usage in publication:
-
- Loretto slate member*
- Modifications:
-
- Revised
- AAPG geologic province:
-
- Lake Superior region
Summary:
Pg. 30 (table 1), 35. Loretto slate member of Vulcan iron-formation of Menominee group (reinstated) of Animikie series. Rank reduced and reallocated to Vulcan iron-formation where it forms upper member of formation. Overlies Curry iron-bearing member; locally, unconformably underlies Goodrich quartzite of Baraga group (new). Present in Iron and Dickinson Counties, northwestern Michigan (Lake Superior region). Age is considered middle Precambrian (Animikie Series). Report includes stratigraphic sequence chart.
Source: US geologic names lexicon (USGS Bull. 1200, p. 2231); supplemental information from GNU records (USGS DDS-6; Reston 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 ([ ]).