Loft beds are excellent space saving ideas for small rooms, they can make a design more functional and comfortable.
Some Basic Vocabulary in HISTORICAL GEOLOGY
One of the core studies in Earth System Science
Historical geology uses the principles of geology to reconstruct and understand the history of the Earth.
- FOCUS: geologic processes that change the Earth’s surface and subsurface;
- METHODS: uses stratigraphy, structural geology and paleontology to sequence geologic processes;
- COMPLEMENTS / INTEGRATES WITH: study of the evolution of plants and animals over geologic time.
A stratum (plural: strata) is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers. The stratum is the fundamental unit in a stratigraphic column and forms the basis of the study of stratigraphy.
A stratigraphic column typically shows a sequence of sedimentary rocks. The underlying principle is that the oldest rocks are on the bottom and the youngest are at the top.
A formation consists of a certain number of rock strata that are similar in terms of such characteristics as rock type (lithology) or fossil inclusions. Formations are not defined based on the overall thickness of their rock strata.
A formation may be subdivided into members.
A set of formations is called a group.
 Stratigraphic column of the Grand Canyon, Arizona, USA [source]
 A geologic cross section of the Grand Canyon. Black numbers correspond to groups of formations and white numbers correspond to formations. [Here’s a basic key to the humbers in this graphic; and here’s a much more detailed account.]
 Cross section showing Steno’s principle of horizontal (or lateral) continuity in sedimentary rock strata: that layers of sediment initially extend laterally in all directions and therefore rocks that are otherwise similar, but are now separated by, for example, a valley, can be assumed to be originally continuous.
MAIN SOURCE: Wikipedia articles