Answer:
B. fossil content and spatial relationships among sedimentary rocks
Explanation:
Earth's geological scale. Geological division of the Earth from its origins 4.5 billion years ago, to the present. divided into four Hadeic, Archeozoic, Proterozoic and Phanerozoic eons, their names refer to the evolution of terrestrial life. These divisions do not have an exact temporal value, the extent of each division and subdivisions are marked by the geological evolution of the planet not by exact periods of time.
This division can be done thanks to the study of the different<u> fossils found and the analysis of the different sedimentary rocks found </u>and their relationship with the environment in which they are found.
The Phanerozoic eon, which we know best thanks to the existence of visible fossils, is divided into three ages: it was Paleozoic, it was Mesozoic and it was Cenozoic. The ages, in turn, are divided into periods, these in times and the latter in ages. Geological time is framed in a macro-temporal scale of variable stages that depend largely on large geological events that occurred during the history of the planet. It is called Precambrian all the time prior to the Phanerozoic eon, that is, it would include the three previous eons.
Recently the name Ediacariense has been added to designate a period (635Ma-540Ma), located at the end of the Precambrian, and whose name derives from the appearance of new animals and up to half a meter in size (Ediacara fauna). The precambrian is a supereón, which is the division on the geological scale above the eons, this being so large they lack importance for the study of the geological history of the planet.
