A petrographic province is a

geological Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Eart ...

region within which the

igneous rocks Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or ...

reveal a relationship (so-called consanguinity) in

chemical A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wi ...

composition, which may be referred to a community of origin. This relationship may be chemically a close one, but the rocks have widely varying

mineralogical Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proce ...

composition, or the kinship may be restricted to one or more of the chemical components in the rocks.

Etymology

Petrography Petrography is a branch of petrology that focuses on detailed descriptions of rocks. Someone who studies petrography is called a petrographer. The mineral content and the textural relationships within the rock are described in detail. The classi ...

derives from ( el, πέτρα), meaning 'rock', and ( el, γράφειν), 'to write'.

References

* {{Cite NIE, wstitle=Petrographic Province, short=x, vb=x Petrology