geo 416s - Module 1

What is a sediment

any loose particle or grain

What is a sedimentary rock

Rock composed of a collection of sediment grains

How does a sediment turn into a rock

Sediment production via weathering →Transportation/Erosion/Deposistion → Accumulation → Diagenisis/Lithification

What is mechanical compaction

loss of porosity by rearrangment due to overburden pressure

What is lithification

when loose sediment becomes rock by the formation of sediment

What proccesses are associated with diagenisis

Lithification and Mechanical compaction

What are the three types of sedimentary deposits?

silicicastic sediments, chemical sediments and biogenic sediments

What are siliciclastic sediments

sediments formed from weathering/erosion of older silicate rock

what are chemical sediments

formed from direct inorganic precipitation of minerals

what are biogenic sediments

precipitate formed through a biogenic agent

what are the properties of grains

grain size, sorting, and roundness

What determines the textural maturity of a sedimentary rock

roundness, sorting, presence of clay matrix

What is porosity and what is it a function of

The total amount of inter-granular space, it is a function of sorting

What is permeability and what is it a function of?

How fluids move through a deposit, it is a function of sorting and grain size

If a sediment is coarse and well sorted, describe its porosity and permeability

It will have high permeability and porosity

What is the difference between weathering and erosion?

Weathering is the breakdown of material while erosion is the movement of the broken up materials

what are the three products of weathering

sediment, secondary (clay) minerals, and dissolved ions

In what enviroments is physical weathering dominant in?

Cold, dry, high relief enviroments

In what enviroments is chemical weathering dominant in?

Warm and wet enviroments

What are some factors of chemical weathering rates

grain size ( smaller = more rapid)
climate
vegetation
protolith

Why does the protolith affect chemical weathering rates

What are the types of chemical weathering

Dissolution, Hydrolosis, Redox

What is silicate weathering

Explain the chemical equation for silicate weathering

What is a framework grain

What is a matrix

On this photo identify which is a framework grain, matrix and cement:

What are the 2 different types of quartz? Describe its stability against physical and chemical weathering

Monocrystaline and Polycrystaline, quartz is stable against both types of weathering

What determines composistional maturity?

What is the most common sedimentary grain and why?

quartz because it is the most stable

Is feldspar sediment stable against chemical weathering?

NO

What is provenance?

Describe zircon and its importance

There are 100-1000s of zircons in a sediment, it serves as a time capsule because of its uranium and lead content. we use radioactive dating to figure out its maximum crystalization age

What is bowens reaction series?

The order in which minerals crystalize, olivine → ca rich plagiocase → pyroxine, amphibole → biotite mica, Na rich plagiocase → K-spar → muscovite mica → quartz

What is the relationship between bowens reaction series and goldichs stability series?

The first minerals to crystalize are the most unstable.