The rock scene is scanned, yes. From the creator:

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In the beginning of this year, I traveled to the island Fuerteventura and captured various rock material to test equipment, workflows and develop new content.
Because my stay was short I would not have enough time to capture the entire landscape at the detail needed for a playable environement or game.

Instead I focused on testing a method of capturing (still photogrammetry) that would suit the movie industry better,
to see if it was possible to quickly gather content for offline rendering or used to pre visualize using Unreal engine.
As the game and movie industry are not as far apart, I would still learn about capturing, creating content and what to improve on for my project.

The results are a series of images and video of optimized content that show that it is possible to capture areas within several days,
process them and use them to concept a virtual world.

I revisited the location just a few weeks ago. This time with better equipment, more time to spend and was able to avoid some of the mistakes I made before.
Not only did I recapture areas but went home with enough data to reconstruct 200 individual rocks to create an even more detailed environment using simulation.

Photogrammetry is getting really popular in games (for obvious reasons). Unity recently put out a really detailed guide for how to make this kind of content: https://unity3d.com/files/solutions/photogrammetry/Unity-Photogrammetry-Workflow_2017-07_v2.pdf