Marker Bed

marker bed

[′märk·ər ‚bed]
(geology)
A stratified unit with distinctive characteristics making it an easily recognized geologic horizon.
A rock layer which accounts for a characteristic portion of a seismic refraction time-distance curve.

Marker Bed

 

a bed in rock strata that is distinctive owing to structure, color, great density, the presence of concretions and fossils, or any other features that make it possible to trace it when correlating sections and preparing geological maps. It differs in principle from the stratigraphic horizon, which is based on a set of organic remains and includes beds of different facies types.

References in periodicals archive ?
Cross sections can be fully customized and edited, including reshaping contacts, adding well headers, selecting which layers to visualize, hanging the cross section on a selected reference datum such as mean sea level or a marker bed, and exporting the cross section into Voxler 3 for true 3D visualization.
The top of the lower section of the Porters Creek Formation is often marked by an indurated, glauconitic siltstone or mudstone that can be used as a marker bed for structural mapping.
The anticlinal interpretation is preferred because the lower Porters Creek siltstone marker bed elevation change is gradual rather than abrupt as would be expected if a fault boundary were crossed.
This assemblage includes a significant limestone marker bed, known as the Sinwa Formation.
Recent fieldwork has been focused on examining the stratigraphic relationships between fossil localities and laterally continuous geological marker beds in the Great Divide Basin.
This reporting is more representative of anticipated mineralized intervals over the initial reporting of visually-logged potash members for Milestone - 001 and Milestone - 002 using marker beds to delineate thicknesses.