Chaotic terrain

Both tectonic cracks and thermally produced Chaotic terrain are caused by tides, and both involve linkage of the underlying ocean to the surface. The darkening associated with each of these formation processes probably involves substances from the ocean, which makes the features visible even at the low resolution of global images like Figure 5. The cracks are caused by tidal stress and the chaos is probably caused by melt-through of patches of crust by tidal heat. 

Figure 6. A portion of Conamara chaos, which lies just south of the lineament intersection mentioned in the caption for Figure 5. Chaotic terrain is characterized by a disrupted older surface, replaced by a lumpy matrix, often with displaced rafts of the older surface.

Chaotic Terrain Low region within heavily cratered uplands that appears to consist of irregular, blocky, fractured landscape. 

Evidence for a warm subsurface ocean comes from the forms of chaotic terrain and the estimate of the age of the surface (Melosh et al., 2002 [227]). In this context the term warm means that most of the ocean is at the temperature of maximum density (Melosh et al., 2004 [228]). 

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