Geological Unit Finder
Any point on Earth: rock unit, age, succession and sources.
Identifies the geological units mapped under any point on Earth from Macrostrat’s integrated global geological map, at every available map scale, with age, lithology, depositional setting and source map; places them on the international time scale, builds the local stratigraphic succession and writes a geological description and interpretation of the site.
Overview
Macrostrat combines more than two hundred geological maps, from global compilations to detailed regional surveys. The finder queries every scale at the point, lists the most detailed first, draws the unit boundary on request and names the place from OpenStreetMap.
Where Macrostrat holds a measured column, the succession is drawn with real thicknesses; elsewhere the map units cropping out within 25 km are ordered by age into a generalised succession, with the age gaps between them. Both can be opened in the Stratigraphic Column Designer.
What you enter · What you get
What you enter
- Any point: tap the map, search a place, enter coordinates or use GPS
What you get
- Units at every map scale with age, lithology, setting and source map
- Unit boundary on the map
- Position on the geological time scale
- Local stratigraphic succession
- Geological description and interpretation
- Links to source maps, literature and imagery
How it works in the field
Method and equations
Data sources
Point queries use the Macrostrat API v2 (mobile/map_query, geologic_units/map, units). Place names come from OpenStreetMap Nominatim. Ages and colours follow the ICS International Chronostratigraphic Chart (2023). Map precision is estimated as 0.5 mm at the scale of the source map.
Who uses it
Standards and references
- Peters, S.E., Husson, J.M. & Czaplewski, J. (2018). Macrostrat: a platform for geological data integration and deep-time Earth crust research. Geochemistry, Geophysics, Geosystems, 19, 1393–1409.
- Cohen, K.M. et al. (2013, updated 2023). The ICS International Chronostratigraphic Chart. Episodes, 36, 199–204.
- FGDC (2006). Digital Cartographic Standard for Geologic Map Symbolization, FGDC-STD-013-2006.
- OpenStreetMap contributors. Nominatim geocoding service (ODbL).
At a glance
- Category
- Field geology
- Runs on
- Phone, tablet and desktop browser
- Export
- PDF report, CSV, GeoJSON, PNG map and figures
- Access
- Subscribers
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