See the Strange, Beautiful Landscapes Revealed by Lasers
▻https://news.nationalgeographic.com/2017/11/maps-lidar-washington-state-laser-scanning-geology
If you were to strip a forest of all its vegetation, what would you see? To find out, Washington state’s government is using airplanes equipped with LIDAR technology to scan the state’s heavily-forested ground. What’s being revealed beneath the trees is a spectacular and strange landscape of hidden geology. Old landslides, abandoned river channels, ancient lava flows, and the tracks of glaciers are suddenly visible in stark relief.
After the devastating Oso landslide in 2014 that killed 43 people in a small town 50 miles outside of Seattle, Washington’s Geological Survey decided to use LIDAR to get a better handle on the state’s geologic hazards. LIDAR, which stands for “light detection and ranging,” works by sending laser light pulses toward a target and measuring the amount of time it takes for those pulses to return. Some of the light is reflected off the tops of trees, and some manages to filter through the trees to be reflected back by the ground. By using just the light reflected from the lowest point, the ground is revealed.
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