What Is in Front of Me? Geology Camera
Point the phone at a mountain: the geological units you are looking at are named on the picture, and photos and videos keep the labels.
Combines the phone’s position, compass and tilt with an elevation model and the geological map. The line of sight is traced through the terrain to the point you are looking at, and the unit there is named with its age, lithology and distance; a strip across the picture shows the units from left to right and the computed skyline is drawn so the compass can be checked. A location sheet gives the elevation, slope, landform, the unit underfoot and around, the local succession, the fossils to look for and the nearest active fault, with a 360° panorama of the units on the skyline. Areas can be saved on the phone beforehand so everything works without a network.
Overview
In the field the hardest question for a student is often the simplest: what is that ridge made of? This tool answers it on the spot and records the answer: photographs and videos carry the position, the direction, the tilt, the time, the unit and the dip you measured, written into the picture.
It is an aid to observation, not a replacement for it: the geological map behind it may be a regional compilation, and the phone compass can be off by several degrees. The drawn skyline shows at once whether the view is aligned, and a correction slider fixes it.
What you enter · What you get
What you enter
- Position from the phone or a tap on the map
- Camera, compass and tilt of the phone
- Field of view and heading correction
- Dip and a note to write on the video (optional)
What you get
- Unit at the crosshair with age, lithology, distance and elevation
- Strip of units across the picture and computed skyline
- Photos and videos with labels burned in
- Location sheet: elevation, slope, aspect, landform, units, succession, fossils, nearest active fault
- 360° panorama of the units on the skyline
How it works in the field
Method and equations
Direction of view
The device orientation (alpha, beta, gamma) is turned into the direction of the back camera through the rotation matrix of the W3C specification; magnetic declination from the IGRF model converts it to true north.
Line of sight
From an eye 1.6 m above the ground the ray is stepped outward and compared with the terrain, corrected for the curvature of the Earth and refraction, until it meets the ground; the unit is read from the map polygons at that point.
Landform
Slope and aspect by Horn’s method over 30 m; landform from the topographic position index, the difference between the point and the mean of a 300 m ring.
Accuracy and error limits
- The direction of view is as good as the phone compass, typically ±5–15° and worse near vehicles and metal; after aligning the drawn skyline with the real one it is about ±2°. With the 30 m elevation model the point seen is located to tens of metres within a few kilometres. The unit named is as good as the geological map: names and ages are reliable, boundaries may be hundreds of metres to kilometres off where the map is a regional compilation.
- What is not covered: units too small for the map, vegetation, soil and debris covering the rock, buildings, and anything farther than about 8 km. The colour hint compares the average colour at the crosshair with typical outcrop colours of nearby formations; light, shadow and weathering change colour, so it is only a hint.
- To reduce the error: calibrate the compass by moving the phone in a figure of eight, keep away from the car, align the drawn skyline with the real skyline using the correction, use the camera at its normal zoom, and confirm the unit with a hand lens, acid and the fossils.
Who uses it
Standards and references
- W3C (2023). DeviceOrientation Event Specification. World Wide Web Consortium.
- Alken, P. et al. (2021). International Geomagnetic Reference Field: the thirteenth generation. Earth, Planets and Space, 73, 49.
- Horn, B.K.P. (1981). Hill shading and the reflectance map. Proceedings of the IEEE, 69(1), 14–47.
- Weiss, A. (2001). Topographic position and landforms analysis. ESRI User Conference, San Diego.
- 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(4), 1393–1409.
- Styron, R. & Pagani, M. (2020). The GEM Global Active Faults Database. Earthquake Spectra, 36(1_suppl), 160–180.
- Jassim, S.Z. & Goff, J.C. (eds.) (2006). Geology of Iraq. Dolin, Prague and Moravian Museum, Brno.
At a glance
- Category
- Field geology
- Runs on
- Phone, tablet and desktop browser
- Export
- Photos (JPG) and videos (MP4 or WebM) with labels; panorama as PNG, JPG and PDF; full PDF report
- Access
- Free
Run this survey on your next site
All 64 tools, report export and the AI assistant come with one subscription.