A UC geologist uses 3-D to study cliff landscapes
A camera and a computer may be all it takes to scientifically map earth formations.
Using a regular camera with Agisoft Photoscan software UC Geology Professor Dylan Ward pitched his tent at the bottom of a cliff near Ferron, Utah in May and began clicking away. He took 900 digital images at the base and once back in Cincinnati loaded them into the computer.
The software, using a method called Structure-From-Motion Photogrammetry, crunched through all the images and found common features from different angles. According to Ward, "Every point you are seeing here is a point that it found in common between three or more of these photographs and I can turn on the camera positions here so you can see it reconstructs where each camera was."
Ward says the computer program uses the same principles that allow humans to see 3-D.
The software then analyzes and measures to create a complete picture like this:
After the 3-D image , the next step is to put the Utah cliffs data in a geographic information systems program. It will make measurements of the detailed topography of the channels and the hilltops on the slope below the cliffs. It can also make detailed measurements on the size of the boulders. Ward then can get a sense for whether the presence of all of this rock fall debris is slowing down the rate that the cliffs are retreating.
In a couple of years Ward says he would like to go back to Utah and resurvey and figure out the rate of erosion in this landscape.
Ward is in Vancouver explaining to other geologists how they can use the 3-D photo method at the Geological Society of America annual meeting.