Source report. The US Geological Survey says its cooperative national geologic map now covers all states and US territories.
Source: US Geological Survey. Original source published 3 September 2026. Published on Alder Atlas: 14 September 2026.
What the source says
Geologic maps describe rock, sediment and related features. They can inform questions about groundwater, resources, infrastructure and hazards.
Why it matters
A nationwide map is a scientific reference, not a guarantee about a particular parcel of land. Its value comes from accessible, comparable evidence.
What the report does not establish
Map coverage does not replace site-specific studies. Resolution and field evidence remain important.
What to watch next
Map documentation and access tools explain the scale and limits of the data.
Sources & further reading
This is an independently worded, source-based report prepared with AI assistance for the Alder Atlas editorial project. It is not first-hand reporting.