The layers correspond to the environment or scope in which their services operate.
There are four superimposed instrumental layers corresponding to different musical processes.
The oldest layer built of bricks and stone probably corresponds to the fortress besieged by Alexander.
The urban layer corresponded to the municipal authority.
The metropolitan layer corresponded to the regional (Comunidad) authority.
In the layer of rock corresponding to the extinction, the scientists found elevated amounts of the rare element iridium.
Within this double layer, the first layer corresponds to the charged surface.
A paired (black and white) layer of the varved lake sediments correspond to a year.
As in medieval allegory, multiple layers of meaning correspond to the novel's multiple languages.
These layers correspond to the lexical, syntactic and semantic layers from formal language theory.