If you are interested in our ONLINE INTERACTIVE MAPS, please visit our Washington State Geologic Information Portal menu page.
The maps distributed here are digital versions of printed maps in PDF. Maps older than a decade are generally scans of paper maps. Newer maps were generated digitally with programs such as Esri’s ArcGIS and Adobe Illustrator.
The majority of these online maps were produced by DGER, but we also link to some from other agencies, such as the U. S. Geological Survey (USGS).
Our online maps are divided into 3 general categories:
Geology / Hazards / Resources
Geologic maps are primarily (but not limited to) surface geology maps. They depict rock types and ages, as well as geologic structures (such as folds and faults) found at the surface of the mapped region.
Geologic hazard maps include maps that show general slope stability and landslide hazards, earthquake and liquefaction hazards, and tsunami hazards, as well as some waste disposal planning maps. Map scales vary from 1:24,000 to statewide.
Geologic resource maps include mineral resource maps, rock aggregate and sand & gravel maps, and coal reserve maps. Map scales vary from 1:24,000 to statewide.
Surface geology maps are organized by commonly used map scales. (Hazard and Resource maps are organized by region.) The map scale relates distance on the map to the distance on the actual ground. For example, in a 1:24,000 scale map, one inch on the map represents 24,000 inches on the ground. Therefore, larger scale ratios (for example, 1:24,000) are used to depict smaller areas (typically a few miles across), while smaller scale ratios like 1:500,000 are used to map large (commonly state-wide) areas.
Finding a Map
You can search for a map in a number of ways:
- If you know the quadrangle or general area that interests you, you can locate them on one of the Geology / Hazards / Resources index maps.
- You can also use the Online Maps Index spreadsheet to identify and download a map. This is a sortable Excel file that can be ordered by type, scale, region, author, title, year published, and publication series. Hyperlinks are provided in the spreadsheet for direct download of map products.
- If you know specific search terms, such as author or title, you can enter them in the “Advanced Search” box at the top right of this page.