(of rock) that has formed from sediment deposited by water or air.
denoting rock that has undergone transformation by heat, pressure, or other natural agencies, e.g., in the folding of strata or the nearby intrusion of igneous rocks.
(of rock) having solidified from lava or magma
is a system or formation of layers, classes, or categories.
the landform layers can be estimated age because how ever many layers are there will be how old it is and some trees that are in the forest can be have a estimated age