Assise
Encyclopedia
An assise is a geological term for two or more beds or strata
of rock
united by the occurrence of the same characteristic species or genera.
Stratum
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...
of rock
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...
united by the occurrence of the same characteristic species or genera.