The Dorsal Tesseract is defined by its relative lack of geological activity. Because it is adjacent to the wet Western Tesseract and lacks much in the way of terrain elevation due to its Dorsal location, Dorsal A is taken up almost entirely with wetlands of varying depth. In places where the water has sat for a long time, the water table can extend almost all the way down to the cube's thin magma layer, creating warm spots. Unlike most cubes, the geophysical cycles of the cube are defined less by geological activity than by biological activity - deep-rooted mangroves and a plethora of aquatic plants serve to draw the normally scarce nutrients of the Distal soil up to the surface for use by the organisms there, while the soggy terrain sucks many creatures which visit from adjacent cubes or tesseracts down to become more fertilizer.
Fauna & Flora
Rose, sage, and ash meantwigs proliferate in mangroves in The Everswamp. Ash meantwigs serve as apex predators in that environment, while rose and sage varieties serve the role of scavengers and decomposers. Fish in the shallows live by eating the fruits and scraps of the meantwigs (as well as eachother), while chemosynthetic tube worms in the deeper waters rely on the meager heat and nutrients provided by the sparse underwater geothermal vents. Most non-aquatic animal life comes in the form of birds and small, arboreal mammals; most terrain is too mushy to support large terrestrial animals.
The proliferation of plant life in The Everswamp suggest that there might be rich petroleum reserves accumulating in the deeper recesses of the water; a lack of solid foundations for wells, however, would make extraction of these resources impractical.
With very little dry land for airships to land on, The Everswamp sees little in the way of casual tourism. Occasionally, explorers from other regions of the Manifold (especially the Rostran Archipelago Confederacy due to their nautical acumen) will arrive to gather samples or even capture wild meantwigs for domestication purposes. Military conflicts in the region are rare, but there are a few airship hulks sitting at the bottom of The Everswamp.