All Topics  
Stratum

 
Stratum

 
   Email Print
   Bookmark   Link
 

 

Stratum
 
 
  Topics Stratum Topic Home

In geology
Geology

Geology is the science and study of the solid and liquid matter that constitute the Earth. The field of geology encompasses the study of the composition, structural geology, physical properties, dynamics, and History of the Earth of Earth materials, and the processes by which they are formed, moved, and changed....
 and related fields, a stratum (plural: strata) is a layer of rock
Rock (geology)

In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock....
 or soil
Soil

Soil is the naturally occurring, unconsolidated or loose covering on the Earth's surface. Soil is composed of particles of broken rock that have been altered by chemical and environmental processes including weathering and erosion....
 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
1 E11 mē

To help compare orders of magnitude of different geographical regions we list here surface areas between 100,000 square kilometre and 1,000,000 km?....
 of the Earth
Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
's surface. Strata are typically seen as bands of different colored or differently structured material exposed in cliff
Cliff

In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them....
s, road
Road

A road is an identifiable Road number, way or Trail between Location . Roads are typically smoothed, Pavement , or otherwise prepared to allow easy travel; though they need not be, and historically many roads were simply recognizable routes without any formal construction or Maintenance, repair and operations....
 cuts, quarries
Quarry

A quarry is a type of open-pit mining from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone....
, and river
River

A river is a natural stream of water, usually freshwater, flowing toward an ocean, a lake, or another stream. In some cases a river flows into the ground or dries up completely before reaching another body of water....
 banks.






Discussion
Ask a question about 'Stratum'
Start a new discussion about 'Stratum'
Answer questions from other users
Full Discussion Forum



Encyclopedia


In geology
Geology

Geology is the science and study of the solid and liquid matter that constitute the Earth. The field of geology encompasses the study of the composition, structural geology, physical properties, dynamics, and History of the Earth of Earth materials, and the processes by which they are formed, moved, and changed....
 and related fields, a stratum (plural: strata) is a layer of rock
Rock (geology)

In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock....
 or soil
Soil

Soil is the naturally occurring, unconsolidated or loose covering on the Earth's surface. Soil is composed of particles of broken rock that have been altered by chemical and environmental processes including weathering and erosion....
 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
1 E11 mē

To help compare orders of magnitude of different geographical regions we list here surface areas between 100,000 square kilometre and 1,000,000 km?....
 of the Earth
Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
's surface. Strata are typically seen as bands of different colored or differently structured material exposed in cliff
Cliff

In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them....
s, road
Road

A road is an identifiable Road number, way or Trail between Location . Roads are typically smoothed, Pavement , or otherwise prepared to allow easy travel; though they need not be, and historically many roads were simply recognizable routes without any formal construction or Maintenance, repair and operations....
 cuts, quarries
Quarry

A quarry is a type of open-pit mining from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone....
, and river
River

A river is a natural stream of water, usually freshwater, flowing toward an ocean, a lake, or another stream. In some cases a river flows into the ground or dries up completely before reaching another body of water....
 banks. Individual bands may vary in thickness from a few millimeters to a kilometer or more. Each band represents a specific mode of deposition
Deposition

Deposition or Depose may refer to:* Deposition , taking testimony outside of court* Deposition , molecules settling out of a solution* Thin-film deposition, any technique for depositing a thin film of material onto a substrate or onto previously deposited layers...
 -- river silt
Silt

Silt is soil or Rock derived granular material of a Particle size between sand and clay. Silt may occur as a soil or as suspended sediment in a surface water body....
, beach sand
Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.As the term is used by geologists, sand particles range in diameter from 0.0625 to 2 millimeters....
, coal swamp
Swamp

A swamp is a wetland featuring temporary or permanent inundation of large areas of land, by shallow bodies of water. A swamp generally has a substantial number of hammock , or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation....
, sand dune, lava
Lava

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 ....
 bed, etc.

Geologist
Geologist

For other uses, see Geologist .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 ....
s study rock strata and categorize them by the material in the beds. Each distinct layer is usually assigned to a "formation
Geologic formation

A formation or geological formation is the fundamental unit of lithostratigraphy. A formation consists of a certain number of rock stratum that have a comparable lithology, sedimentary facies or other similar properties....
" name usually based on a town, river, mountain, or region where the formation is exposed and available for study. For example, the Burgess Shale
Burgess Shale

The Burgess Shale Formation is one of the world's most celebrated fossil localities, and is famous for the exceptional preservation of the fossils found within it, in which the soft parts are preserved....
 is a thick exposure of dark, occasionally fossil
Fossil

Fossils are the preserved remains or trace fossil of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous Rock formations and sedimentary rock layers is known as the fossil record....
iferous, shale
Shale

Shale is a fine-grained sedimentary rock whose original constituents were clay minerals or muds. It is characterized by thin laminae breaking with an irregular curving fracture, often splintery and usually parallel to the often-indistinguishable bedding plane....
 exposed high in the Canadian Rockies
Canadian Rockies

The Canadian Rockies comprise the Canada segment of the North American Rocky Mountains mountain range. The southern end in Alberta and British Columbia borders Idaho and Montana of the United States....
 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
Stratigraphy

Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary rock and layered volcanic rocks....
.

When planning civil engineering projects or other large constructions, the strata of the area where the construction takes place is a significant factor in design decisions. For example if a canal is to be built on a route where the strata are not watertight, the canal will have to be lined with some form of waterproof material (usually clay).

Image:Strata-french-alps.jpg|Strata on a mountain face in the French Alps Image:Rockstrata3435.JPG|Interstate road cut through limestone
Limestone

File:Limestone Formation In Waitomo.jpgLimestone is a sedimentary rock composed largely of the mineral calcite . The deposition of limestone strata is often a by-product and indicator of biological activity in the geology record....
 and shale
Shale

Shale is a fine-grained sedimentary rock whose original constituents were clay minerals or muds. It is characterized by thin laminae breaking with an irregular curving fracture, often splintery and usually parallel to the often-indistinguishable bedding plane....
 strata in East Tennessee
Tennessee

Tennessee is a U.S. state located in the Southern United States United States. In 1796, it became the sixteenth state to join the United States....
 Image:Rock_Strata.jpg|Rock strata at Depot Beach, New South Wales
New South Wales

New South Wales is Australia's oldest and most populous States and territories of Australia, located in the south-east of the country, north of Victoria and south of Queensland....
 Image:Rainbow_Basin.JPG|Rainbow Basin Syncline near Barstow, California
Barstow, California

Barstow is a city in San Bernardino County, California, California, United States. The population was 21,119 at the 2000 census.Barstow is a major regional transportation center....
. Folded strata. Image:OrdOutcropTN.JPG|Outcrop of Upper Ordovician limestone and minor shale, central Tennessee; College of Wooster students. Image:Geology_of_Cyprus-Chalk.jpg|Chalk Layers in Cyprus
Cyprus

Cyprus , officially the Republic of Cyprus , is an island country situated in the eastern Mediterranean Sea, east of Greece, west of Lebanon, Syria, and Israel, south of Turkey and north of Egypt....
 - showing classic layered structure. Image:HeavyMineralsBeachSand.jpg|Heavy minerals (dark) as thin strata in a quartz beach sand (Chennai
Chennai

Chennai , formerly Indian renaming controversy , is the fourth largest metropolitan area of India and the capital city of the Indian states and territories of India of Tamil Nadu....
, India).

See also

  • Stratigraphy
    Stratigraphy

    Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary rock and layered volcanic rocks....
  • Polystrate fossil
    Polystrate fossil

    A polystrate or upright fossil describes a fossil of a single organism that runs through more than one geological stratum. Entire "fossil forests" have been discovered....
  • Important publications in stratigraphy
    List of publications in geology

    Foundations...
  • Archaeology
    Archaeology

    Archaeology, archeology, or arch?ology is the science that studies Homo cultures through the recovery, documentation, analysis, and interpretation of material remains and environmental data, including architecture, Artifact , features, Biofact s, and cultural landscape....
  • Geologic map
    Geologic map

    A geologic map or geological map is a special-purpose map made to show geological features.The stratigraphic contour lines are drawn on the surface of a selected deep stratum, so that they can show the topographic trends of the strata under the ground....
  • Geologic unit
    Geologic unit

    A geological unit is a volume of Rock or Glaciology of identifiable origin and age range that is defined by the distinctive and dominant, easily mapped and recognizable petrology, lithology or paleontology features that characterize it....
  • Geologic formation
    Geologic formation

    A formation or geological formation is the fundamental unit of lithostratigraphy. A formation consists of a certain number of rock stratum that have a comparable lithology, sedimentary facies or other similar properties....
  • Archaeological horizon


External links