What is textural maturity in geology?
Maturity refers to the degree to which clastic sediment has been modified by physical and chemical processes at Earth’s surface. Textural maturity refers to the degree to which physical characteristics of grains and populations of grains approach the “ultimate end product” (Pettijohn, 1975, p. 491).
What is foliated in geology?
What is a Foliation? A foliation is any sort of fabric-forming planar or curved planar geologic structure in a metamorphic rock, but could additionally include sedimentary bedding or magmatic layering (Wilkerson, 2019). A foliated rock holds a parallel alignment of certain minerals that are repetitively layered.
How do foliation rocks develop?
Foliation forms when pressure squeezes the flat or elongate minerals within a rock so they become aligned. These rocks develop a platy or sheet-like structure that reflects the direction that pressure was applied.
What is foliation in sedimentary rocks?
Foliation in geology refers to repetitive layering in metamorphic rocks. Each layer can be as thin as a sheet of paper, or over a meter in thickness. Rocks exhibiting foliation include the standard sequence formed by the prograde metamorphism of mudrocks; slate, phyllite, schist and gneiss.
Which is the best description of textural maturity?
textural maturity An expression of the sorting, matrix content, and grain angularity in a sediment. An immature sediment is one with poor sorting, a large proportion of matrix, and angular particles.
Where does the word foliation come from in geology?
Foliation in geology refers to repetitive layering in metamorphic rocks. Each layer may be as thin as a sheet of paper, or over a meter in thickness. The word comes from the Latin folium, meaning “leaf”, and refers to the sheet-like planar structure.
What kind of foliation is found in medium grade rocks?
Foliation in medium-grade rocks defined by the alignment of metamorphic mica (platy minerals), (Wilkerson, Per. Comm., 2019). The image on the right is a personal photograph of foliated schist from the DePauw University Rock Room.
When was the scale of textural maturity invented?
In sedimentary rock: Texture …this property, a scale of textural maturity that involved four textural stages was devised in 1951.