Question

Name common four common penetrative lineations (mineral lineation, stretching lineation, crenulation lineation, foliation intersection lineation) and be able to define all of them

Answer 1

The Four common penetrative liberation's are

1. Mineral Lineration

2. Stretching Lineration

3. Crenulation Lineration

3. Foliation intersection Lineration

1. Mineral Lineration:

A lineation is any linear feature or element in a rock , and can occur as the product of tectonic, mineralogical, sedimentary, or geomorphic processes. Lineations are the one-dimensional counterparts of foliations, and both are part of the fabric (geometric organization of features) of a rock.

2. Stretching Lineration:

Stretching lineations are formed by shearing of rocks during asymmetric deformation of a rock mass. ... This is parallel to the direction in which a shearing force, as found in a shear zone, stretches the rock. Shortening occurs at the same time as elongation but in a perpendicular sense to thestretched rod.

3. Crenulation Lineration:

In a geological context, crenulation orcrenulation cleavage is a fabric formed in metamorphic rocks such as phyllite, schist and some gneiss by two or more stress directions causing the formation of the superimposed foliations.

4. Foliation intersection Lineration:

The trace of bedding on anintersecting foliation plane commonly appears as colour stripes generally parallel to local fold's hinges.Intersection lineations can also be due to the intersection of two foliations.Intersection lineations are measured in relation to the two structures whichintersect to form them.