- Date
- 1987
- Eras
- Modern era
- Concepts
- geologyenvironmentland-survey
Summary
Milstein’s 1987 Bedrock Geology of Michigan is the held statewide map behind the bedrock-unit vocabulary used in the project’s archipelago geology records. It places the Garden Island Formation, Bois Blanc Formation, Detroit River Group, and other units in a Michigan-wide geological framework.
Evidence and limits
The map is useful for regional bedrock interpretation and for tracing the authority of current GIS unit names. Its 1:500,000 scale does not prove an outcrop, depth to bedrock, fossil occurrence, quarry location, or geotechnical condition at any named island site. A formation named for Garden Island is not, by name alone, proof of a particular exposure there.
See also
Sources
- Held statewide map labels bedrock units including the Garden Island Formation, Bois Blanc Formation, and Detroit River Group. It provides regional map context for the subsequent state and federal GIS layers, not a record that a particular unit is exposed at a named shore or construction site.geology · publications · milstein_1987_bg01
- Project provenance sidecar for the 1987 Bedrock geology map.Records the source URL, retrieval timestamp, checksum, file size, and host/license note for the held PDF. No public copy of this file is known; the archive holds one and can provide it on request.geology · publications · milstein_1987_bg01.provenance
Added 2 August 2026 · revised 4 August 2026. Recent changes
Cite this article
Beaver Island Archive, “Bedrock geology of Michigan, 1987”, https://beaverislandarchive.org/documents/milstein-bedrock-geology-of-michigan-1987/, accessed [date], citing R. L. Milstein, compiler, *Bedrock Geology of Michigan*, Michigan Department of Natural Resources, Geological Survey Division, Publication BG-01 (1987), scale 1:500,000. (and 1 further source listed on the page).
Last revised 2026-08-04. Fill in [date] with the date you read it — this page is static and cannot know that.
BibTeX for “Bedrock geology of Michigan, 1987”RIS for “Bedrock geology of Michigan, 1987”