User:Mamayuco/sandboxa

Propose moving 30+ categories with similar names:

‎*Category:Archean igneous petrology to Category:Archean magmatism
 * Category:Holocene igneous petrology to Category:Holocene magmatism
 * Category:Pleistocene igneous petrology to Category:Pleistocene magmatism
 * Category:Quaternary igneous petrology to Category:Quaternary magmatism
 * Category:Pliocene igneous petrology to Category:Pliocene magmatism
 * Category:Miocene igneous petrology to Category:Miocene magmatism
 * Category:Neogene igneous petrology to Category:Neogene magmatism
 * Category:Oligocene igneous petrology to Category:Oligocene magmatism
 * Category:Eocene igneous petrology to Category:Eocene magmatism
 * Category:Paleocene igneous petrology to Category:Paleocene magmatism
 * Category:Paleogene igneous petrology to Category:Paleogene magmatism
 * Category:Cenozoic igneous petrology to Category:Cenozoic magmatism
 * Category:Cretaceous igneous petrology to Category:Cretaceous magmatism
 * Category:Jurassic igneous petrology to Category:Jurassic magmatism
 * Category:Triassic igneous petrology to Category:Triassic magmatism
 * Category:Mesozoic igneous petrology to Category:Mesozoic magmatism
 * Category:Permian igneous petrology to Category:Permian magmatism
 * Category:Carboniferous igneous petrology to Category:Carboniferous magmatism
 * Category:Devonian igneous petrology to Category:Devonian magmatism
 * Category:Silurian igneous petrology to Category:Silurian magmatism
 * Category:Ordovician igneous petrology to Category:Ordovician magmatism
 * Category:Cambrian igneous petrology to Category:Cambrian magmatism
 * Category:Paleozoic igneous petrology to Category:Paleozoic magmatism
 * Category:Phanerozoic igneous petrology to Category:Phanerozoic magmatism
 * Category:Neoproterozoic igneous petrology to Category:Neoproterozoic magmatism
 * Category:Mesoproterozoic igneous petrology to Category:Mesoproterozoic magmatism
 * Category:Paleoproterozoic igneous petrology to Category:Paleoproterozoic magmatism
 * Category:Proterozoic igneous petrology to Category:Proterozoic magmatism
 * Category:Neoarchean igneous petrology to Category:Neoarchean magmatism
 * Category:Paleoarchean igneous petrology to Category:Paleoarchean magmatism
 * Category:Precambrian igneous petrology to Category:Precambrian magmatism

‎The rationales is that "igneous petrology" is inadequate and magmatism both more precise and clear. These categories group two types of article: 1) articles about volcanism and volcanic rocks and 2) articles about intrusions. Both of these kind of rocks and phenomenta are derived from the artivitiy of molten rock under earth's surface, that is magma. Igneous and magmatic rocks are the same, but petrology refers to a science. By analogy do we talk about concise Category:Freshwater molluscs or about Category:Freshwater malacology?

A secondary reason is that igneous petrology sounds extraneous to those unfamiliar with geology while magmatism is easier to grasp.