Prismatic
Encyclopedia
In geology
and petrology
, a prism is a long, narrow, wedge-shaped sedimentary body with a width to thickness ratio greater than 5 to 1 but less than 50 to 1, and a length 1.5 to 3 times its width.
These types of sediments are typically formed during orogenic
deformation. For example, the arkose
s found in fault troughs.
"Prismatic" is also type of mineral habit (appearance of a crystal). Prismatic minerals have crystals that show a uniform cross-section
.
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
and petrology
Petrology
Petrology is the branch of geology that studies rocks, and the conditions in which rocks form....
, a prism is a long, narrow, wedge-shaped sedimentary body with a width to thickness ratio greater than 5 to 1 but less than 50 to 1, and a length 1.5 to 3 times its width.
These types of sediments are typically formed during orogenic
Orogeny
Orogeny refers to forces and events leading to a severe structural deformation of the Earth's crust due to the engagement of tectonic plates. Response to such engagement results in the formation of long tracts of highly deformed rock called orogens or orogenic belts...
deformation. For example, the arkose
Arkose
Arkose is a detrital sedimentary rock, specifically a type of sandstone containing at least 25% feldspar. Arkosic sand is sand that is similarly rich in feldspar, and thus the potential precursor of arkose....
s found in fault troughs.
"Prismatic" is also type of mineral habit (appearance of a crystal). Prismatic minerals have crystals that show a uniform cross-section
Cross section (geometry)
In geometry, a cross-section is the intersection of a figure in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc...
.