The Crater

The Crater is the area in which the main story of Subnautica takes place. The Crater and Sector Zero are the two major ecosystem centers known on Planet 4546B.

Geological Information
The area is the crater of a huge, long-dormant undersea volcano approximately three kilometers in height and varies from 3.3 to 4.3 kilometers in diameter. After the volcano became dormant the crater was filled in by sediments and the once volatile volcano became the center of a diverse and thriving ecosystem.

The area is likely a guyot; a type of undersea volcanic formation that once protruded above the surface and has now been eroded into a tabletop below the ocean's surface.

The area around the volcano is known as the dead zone or crater edge. It is a vast expanse of featureless water inhabited only by plankton and their planktivorous Leviathan class predators. It is unknown how large this stretch of ocean is.

Within the crater are multiple ecological Biomes. Each is diverse in its very own way. Biomes range from Underwater Islands to Kelp Forests, each supporting their own unique Fauna and Flora.

Trivia

 * Although the size of the Crater is stated to be 2km x 2km in the Crater Edge Databank entry, the actual size in game is about twice that.


 * Before the Big Little Update, the Crater used to have more realistic terrain at around 3000 meters depth surrounding it, giving an appearance similar to real world abyssal plains. The bottom of the Crater was found here, which was a relatively flat area that covered a 4km x 4km square. At 3040 meters depth, the world completely cut off and all terrain would cease. It is unknown why this terrain was removed.