Textures Of Siliciclastic Rocks

Question 1

What are the three components of a clastic sedimentary rock?

Answer 1

1) Framework: coarser grained components (clasts)
2) Matrix: mud, silt, clay
3) Cement: calcite or quartz that binds it together

Question 2

What does the term “fabric” describe?

Answer 2

Fabric is used to describe the organization or arrangement of grains. An example would be grain imbricarion (coarser trained rocks with long axes parallel to one another) and fissility

Question 3

Compare and contrast porosity and permeability

Answer 3

Porosity:
~spaces between grains, volume of pores
~well sorted sediment= good porosity

Permeability:
~interconnectedness of pore spaces, controlled by:
Grain size, sorting, shape and fabric

Question 4

What is textural maturity and what are the four types ?

Answer 4

Textural maturity is the degree to which siliciclastic rocks have been reworked by Erosion and transport processes.
~roundness, sphericity
~amount of matrix
~sorting
Four categories:
Immature, submature, mature, supermature