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Information about Stratum

This article is about the geologic use of the term, for other uses see Stratum (disambiguation)
For other uses, see strata (novel) and strata title.


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Goldenville Strata exposed at a quarry in Bedford, Canada. It is made up of thick layers of ocean sediments that were laid down during the Middle Cambrian period and were subsequently pushed up onto land. This formation now covers over half of the province of Nova Scotia and is recorded as being 29,000 feet in thickness in some areas.


In geology and related fields, a stratum (plural: strata) is a layer of rock or soil with internally consistent characteristics that distinguishes it from contiguous layers. Each layer is generally one of a number of parallel layers that lie one upon another, laid down by natural forces. They may extend over hundreds of thousands of square kilometers of the Earth's surface. Strata are typically seen as bands of different colored or differently structured material exposed in cliffs, road cuts, quarries, and river banks. Individual bands may vary in thickness from a few millimeters to a kilometer or more. Each band represents a specific mode of deposition -- river silt, beach sand, coal swamp, sand dune, lava bed, etc.

Geologists study rock strata and categorize them by the material in the beds. Each distinct layer is usually assigned a "formation" name usually based on a town, river, mountain, or region where the formation is exposed and available for study. For example, the Burgess Shale is a thick exposure of dark, occasionally fossiliferous, shale exposed high in the Canadian Rockies near Burgess Pass. Slight distinctions in material in a formation may be described as "members" or sometimes "beds." Formations are collected into "groups." Groups may be collected into "supergroups."

The stratum is the fundamental unit in a stratigraphic column and forms the basis of the study of stratigraphy.

<gallery widths="180px" perrow=3> Image:Strata-french-alps.jpg|Strata on a mountain face in the French Alps Image:Rockstrata3435.JPG|Interstate road cut through limestone and shale strata in East Tennessee Image:Rock_Strata.jpg|Rock strata at Depot Beach, New South Wales Image:Rainbow_Basin.JPG|thumb|Rainbow Basin Syncline near Barstow, California. Folded strata. Image:OrdOutcropTN.JPG|Outcrop of Upper Ordovician limestone and minor shale, central Tennessee; College of Wooster students. </gallery>

See also

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  • A stratum (plural: strata) is the basic unit of lithologic stratigraphy.
  • In telecommunications, the term stratum is used to describe the quality of a clock used for synchronization. The ANSI Synchronization Interface Standard T1.

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For discussion regarding the term strata as used in geology, see stratum. See also Strata (disambiguation).


Strata is a comic science fiction novel by Terry Pratchett.
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For other uses, see Strata (disambiguation).


Strata title is a form of ownership devised for multi-level apartment blocks, which have apartments at different levels or "strata".
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Oceanic crust      0-20 Ma
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Balanced Rock stands in Garden of the Gods park in Colorado Springs, CO]] A rock is a naturally occurring aggregate of minerals and/or mineraloids. The Earth's lithosphere is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic.
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SOiL is a five-piece Hard Rock band from Chicago, Illinois, United States. They formed in 1997 and are still active. They are signed to DRT Entertainment and have released four albums, their most recent being True Self which was released in March 27 2006.
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1 E+11 m²
  • 38,600 square miles
  • a square with side 316 km
  • a circle with radius 178 km
  • 100,250 km² -- Iceland (land)

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    • EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001. Their greatest hit, their debut single "time after time", peaked at #13 in the Oricon singles chart.
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    cliff or bluff is a significant vertical, or near vertical, rock exposure. Cliffs are categorized as erosion landforms due to the processes of erosion and weathering that produce them. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers.
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    road is an identifiable route, way or path between two or more places.[1] Roads are typically smoothed, paved, or otherwise prepared to allow easy travel;[2]
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    quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone. Quarries are usually shallower than other types of open-pit mines.
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    river is a natural waterway that transits water through a landscape from higher to lower elevations. It is an integral component of the water cycle. The water within a river is generally collected from precipitation through surface runoff, groundwater recharge (as seen at baseflow
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    1 millimetre =
    SI units
    010−3 m 0 cm
    US customary / Imperial units
    010−3 ft 010−3 in
    The millimetre (American spelling: millimeter, symbol mm
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    1 kilometre =
    SI units
    0 m 0106 mm
    US customary / Imperial units
    0 ft 0 mi
    A kilometre (American spelling: kilometer, symbol km
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    Deposition or Depose may refer to:
    • Deposition (law), taking testimony outside of court
    • Deposition (chemistry), molecules settling out of a solution
    • Deposition (sediment), material (like sediment) being added to a landform

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    Silt is soil or rock derived granular material of a specific grain size. Silt may occur as a soil or alternatively as suspended sediment in a water column of any surface water body. It may also exist as deposition soil at the bottom of a water body.
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    Sand is a granular material made up of fine mineral particles. It is a naturally occurring, finely divided rock.

    Sand comprises particles, or granules, ranging in diameter from 0.0625 (or 1⁄16 mm) to 2 millimeters.
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    worldwide view.
    This article is about wetland type (a landform). For other uses of the term "swamp", see Swamp (disambiguation).
    A swamp
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    dune is a hill of sand built by eolian processes. Dunes are subject to different forms and sizes based on their interaction with the wind. Most kinds of dune are longer on the windward side where the sand is pushed up the dune, and a shorter "slip face" in the lee of the wind.
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    Lava is molten rock expelled by a volcano during an eruption. When first expelled from a volcanic vent, it is a liquid at temperatures from 700 °C to 1,200 °C (1,300 °F to 2,200 °F).
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    A geologist is a contributor to the science of geology, studying the physical structure and processes of the Earth and planets of the solar system (see planetary geology).
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    A geologic formation is a formally named rock stratum or geological unit. Formations are Lithostratigraphic units which are defined by primary lithology.

    The concept of formally defined layers or strata is central to the geologic discipline of stratigraphy.
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    The Burgess Shale, named after Burgess Pass, is a Cambrian black shale formation in the Canadian Rockies of British Columbia, Canada. In Yoho National Park, near the town of Field, the Burgess Shale contains a unique and famous fossil bed displaying exceptional preservation
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    For other uses of the term, see Fossil (disambiguation)


    FOSSIL is a standard for allowing serial communication for telecommunications programs under the DOS operating system.
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    Shale is a fine-grained sedimentary rock whose original constituents were clays or muds. It is characterized by thin laminae[1] breaking with an irregular curving fracture, often splintery and usually parallel to the often-indistinguishable bedding plane.
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    Canadian Rockies



    Country | Canada
    Provinces | British Columbia,Alberta

    Highest point | Mount Robson
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    Stratigraphy, a branch of geology, studies rock layers and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy includes two related subfields: lithologic or lithostratigraphy and biologic stratigraphy or
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    Limestone is a sedimentary rock composed largely of the mineral calcite (calcium carbonate: CaCO3). Limestone often contains variable amounts of silica in the form of chert or flint, as well as varying amounts of clay, silt and sand as disseminations, nodules, or layers
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    Shale is a fine-grained sedimentary rock whose original constituents were clays or muds. It is characterized by thin laminae[1] breaking with an irregular curving fracture, often splintery and usually parallel to the often-indistinguishable bedding plane.
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    State of Tennessee

    Flag Seal
    Nickname(s): Volunteer State
    Motto(s): Agriculture and commerce

    Official language(s) English

    Capital Nashville
    Largest city Memphis

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