Describe important textures associated with metamorphic rock.
Answer (1)
Student Expert
6th Dec, 2019
There are two types of textures in Metamorphic Rocks and those are- Foliated and Non Foliated. Due to geological changes these types are created.
Again, Foliated ( caused by pressure) texture can be subdivided in 4 parts on the basis of increasing metamorphic grade. These types of rocks have a layered or banded appearance.
Non Foliated- These rocks formed around igneous intrusions where the temperatures are high but the pressures are relatively low and equal in all directions. Example- Hornfels, marble, quartzite, and novaculite, do not have a layered or banded appearance.
Again, Foliated ( caused by pressure) texture can be subdivided in 4 parts on the basis of increasing metamorphic grade. These types of rocks have a layered or banded appearance.
- Slaty Texture- This texture is caused by the parallel orientation of microscopic grains.
- Phyllitic Texture- This texture is formed by the parallel arrangement of macroscopic grains ( platy minerals, micas).
- Schistose Texture- This texture resulting from the subparallel to parallel orientation of platy minerals such as chlorite or micas.
- Gneissic Texture- This is a coarsely foliated texture in which the minerals have been segregated into discontinuous hands, each of which is dominated by one or two minerals.
Non Foliated- These rocks formed around igneous intrusions where the temperatures are high but the pressures are relatively low and equal in all directions. Example- Hornfels, marble, quartzite, and novaculite, do not have a layered or banded appearance.
Comments (0)
Related Questions
Describe the principles of stratigraphy.
233 Views
