Search results
Results From The WOW.Com Content Network
The three-dimensional orientation of a line can be described with just a plunge and trend. The rake is a useful description of a line because often (in geology) features (lines) follow along a planar surface. In these cases the rake can be used to describe the line's orientation in three dimensions relative to that planar surface.
A horizontal line would have a plunge of 0°, and a vertical line would have a plunge of 90°. [3] [7] A linear feature which lies within a plane can also be measured by its rake (or pitch). Unlike plunge, which is the feature's azimuth, the rake is the angle measured within the plane from the strike line. [3]
Fold axis plunge is measured in dip and dip direction (strictly, plunge and azimuth of plunge). The orientation of a fold axial plane is measured in strike and dip or dip and dip direction. Lineations are measured in terms of dip and dip direction, if possible. Often lineations occur expressed on a planar surface and can be difficult to measure ...
Lineations in structural geology are linear structural features within rocks. [1] There are several types of lineations, intersection lineations, crenulation lineations, mineral lineations and stretching lineations being the most common. Lineation field measurements are recorded as map lines with a plunge angle and azimuth.
Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...
Solidified lava flow in Hawaii Sedimentary layers in Badlands National Park, South Dakota Metamorphic rock, Nunavut, Canada. Geology (from Ancient Greek γῆ (gê) 'earth' and λoγία () 'study of, discourse') [1] [2] is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. [3]
Since the nature of cleavage is dependent on scale, slaty cleavage is defined as having 0.01 mm or less of space occurring between layers. [1] Slaty cleavage often occurs after diagenesis and is the first cleavage feature to form after deformation begins.
Foliation in geology refers to repetitive layering in metamorphic rocks. [1] Each layer can be as thin as a sheet of paper, or over a meter in thickness. [1] The word comes from the Latin folium, meaning "leaf", and refers to the sheet-like planar structure. [1]