Outcrop
Point your camera at the landscape around you to learn about its geology: what the rocks are, when and how they formed, and where the continents were at the time. It also works offline.
Free, for iPhone and Android. Geologic maps worldwide from Macrostrat.
See where each rock fits in Earth’s 4.5-billion-year history.
Hover over or tap the timeline to see periods and events.
Hold your phone up to a canyon wall, a road cut or a distant ridge, and the geologic map is drawn over the landscape. The rock in the center of the screen is identified, and nearby peaks and lakes are labeled. Select a rock to highlight it and gray out everything else.
Outcrop opens to the rock you’re standing on, with its name, its age, what it’s made of and how it formed. Tap anywhere on the map to learn about a different spot.
Where Macrostrat has a stratigraphic column for the area, you can see the layers beneath you from the surface down, with each layer’s age, the gaps in the record and the fossils found in them. Tap a layer to learn more about it.
See the globe as it looked when a rock formed, using Christopher Scotese’s PALEOMAP maps. Outcrop shows where the rock was then, how far it has moved and how fast. Press play to watch plate tectonics carry it to where it is today.
Search for a rock type, an age, a named unit or a fault. Matching places are highlighted on the map, and Outcrop tells you how far away the nearest one is, even if it’s off screen.
Bedrock and faults come from Macrostrat’s geologic maps, which are more detailed in some places than others. Switch to Quaternary geology to see glacial and river deposits and recently active faults, or to Soils to see the soil and the plants that grow in it. All three layers work on the map and in the camera view.
Outline an area to download it to your phone, and the map and camera view will work without a signal. Fossil records and active faults in the camera view still need a connection.
