Our subsurface geology and geophysics data are used to compile 3D visualizations of the earth and can help us to understand the relationship between Washington’s complex geology and the environment. These data are used to evaluate resources and their associated problems, such as groundwater aquifer pollutants and pathways, as well as geologic hazards posed by landslide, earthquake (seismic), and volcanic events. Subsurface data are primarily obtained from geotechnical wells, geophysical surveys, such as seismic shear wave measurements, and water well records. The subsurface data we collect and use in our work is maintained in databases and presented in the Subsurface theme of the online Washington State Geologic Information Portal. You can also download the geodatabase through the portal or directly from our GIS Data and Databases page.
Subsurface data are often available for areas that are currently being mapped. Below is an illustration showing part of the 2013 geologic map of the Sultan 7.5-minute quadrangle draped over topography and intersected by a cross section in the foreground. The colored cylinders represent boreholes for which there are subsurface data used in the construction of the cross section.
Screenshot of a cross section view of the Sultan quadrangle 3D PDF, available for download below.
3D PDFs are a user-friendly way to enjoy visualizations like the one shown above because they can be opened with the freely-available Adobe® Reader® software. Click here to download the user guide explaining how to use 3D PDFs. As these files are very large (~50 MB) we recommend that you right-click and "Save As" so the file will download to your computer rather than rendering through your browser.
Click here to view our 3D PDF tutorial video on YouTube.
Choose a downloadable 3D PDF from the selection below:
Sultan (20 MB)
Seabeck / Poulsbo (54+ MB)
Lofall (17 MB)