How do the layers in exfoliation domes differ from the layers visible in spheroidally weathered ...

The layered appearance of exfoliation domes derives from tension cracks produced by relieved stress.
Exfoliation domes are usually made up of rock masses formed deep underground where pressures are
higher. Once the overlying rock mass is eroded away, the load decreases, and the remaining rock mass
is able to expand and crack. Spheroidally weathered outcrops form mainly by chemical weathering.
Where pressures come into play, they are the result of mineralogical changes, such as clay formation

Tropical areas, such as the Amazon or Congo River basins, are places where chemical weathering
processes progress rapidly. The common denominator there is climate, with rainfall being most
significant.

Jointed masses of rock tend to be broken up into blocks. This increases the surface area that can be
affected by chemical weathering. The corners of blocks have three surfaces compared to two for edges
and one for sides. Because of this, the corners weather faster than the edges, which in turn weather
faster than the sides. The resulting weathering surface becomes spherical, from which the word
spheroidal is derived. Spheroidally weathered rock masses have a concentrically layered appearance.
Many times, the original shape of the individual blocks can still be seen.