Previously Mapped Marine Clay

Fairfax County

Updated Oct 8, 2026

About this dataset

These areas were mapped as marine clays in previous surveys. Marine clays are high shrink-swell soils that can cause foundation distress. They are sometimes referred to as Potomac Clays or Deltaic Clays.

Data and resources (6)

HTML
ArcGIS Hub Dataset
Modified Apr 8, 2026
Open link: ArcGIS Hub Dataset
ArcGIS
ArcGIS GeoService
Modified Apr 8, 2026Map preview available
Open link: ArcGIS GeoService Preview map: ArcGIS GeoService
CSV
CSV
Modified Oct 8, 2026Table and Data API available
Open link: CSV Explore data: CSV
ZIP
Shapefile
Modified Apr 8, 2026Map preview available
Open link: Shapefile Preview map: Shapefile
GeoJSON
GeoJSON
Modified Apr 8, 2026Map preview available
Open link: GeoJSON Preview map: GeoJSON
KML
KML
Modified Apr 8, 2026Map preview available
Open link: KML Preview map: KML

Prototype by Datopian · not an official government website · data from data.virginia.gov

Previously Mapped Marine Clay

About this dataset

Data and resources (6)

ArcGIS Hub Dataset

ArcGIS GeoService

CSV

Shapefile

GeoJSON

KML