The National Geologic Map Database is migrating to a new infrastructure. We apologize for any service disruptions during this process.

U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Garden Island formation
  • Modifications:
    • Named
  • Dominant lithology:
    • Dolomite
    • Limestone
  • AAPG geologic province:
    • Michigan basin
Publication:

Ehlers, G.M., 1945, Stratigraphy of surface formations, IN Landes, K.K., and others, eds., Geology of the Mackinac Straits region and sub-surface geology of northern Southern Peninsula: Michigan Geological Survey Publication, no. 44, p. 21-120., Also issued as Michigan Geol. Survey Geol. Ser., no. 37


Summary:

Named the Garden Island formation for Garden Island, northeastern MI. Consists of dolomite and dolomitic limestone which occupies a position between Silurian St. Ignace formation and Middle Devonian Bois Blanc formation. Thickness at type locality is 3 feet; maximum thickness probably not more than 25 feet, and average thickness not more than 15 feet. The Garden Island is of Early Devonian age.

Source: 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 ([ ]).

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 21 May 2026 05:04:00 PM MDT