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How do poorly sorted sediments differ from well sorted sediments?

How do poorly sorted sediments differ from well sorted sediments?

1. n. [Geology] Well-sorted sediments are of similar size (such as desert sand), while poorly-sorted sediments have a wide range of grain sizes (as in a glacial till). A well-sorted sandstone tends to have greater porosity than a poorly sorted sandstone because of the lack of grains small enough to fill its pores.

Do poorly sorted sediments have high porosity?

Porosity refers to the capacity of earth materials to hold water in spaces found within and between sediments and rock. Thus, well sorted sediments have higher porosity while poorly sorted sediments have low porosity. Permeability refers to how easily water passes through sediments and rock.

Why do poorly sorted sediments have low porosity?

Poorly sorted sedimentary deposits, in which there is a wide distribution of grain sizes, typically have lower porosity than well-sorted ones (Figure 11). This is because the finer particles are able to fill in spaces between the larger grains.

Where are poorly sorted sediments found?

At the end of a glacier, where ice is melting as fast as it is being supplied from upstream, the sediments are deposited in a terminal moraine, a ridge of poorly-sorted glacial till. Thinner depostits of glacial sediments called a ground moraine or till plain are found behind the terminal moraine.

Where are poorly-sorted sediments found?

Where are well-sorted sediments found?

Beach sediments that have been transported great distances will be sorted according to grain size. For example, Gulf coast sediments may have traveled the length of the Mississippi River. Winnowing of more uniform sediment shapes and sizes results in a beach with well-sorted sediments.

What is the difference between well sorted and poorly sorted sediment?

Very poorly sorted indicates that the sediment sizes are mixed (large variance); whereas well sorted indicates that the sediment sizes are similar (low variance).

What does sorting tell you about sediment transport?

What does sorting tell you? Generally, sediment sorting improves along the sediment transport path. Poorly sorted sediments were usually deposited quickly (e.g. in storm beds or from flows/mudflows. Better sorted sediments may have been reworked by wind or water. (e.g. Sand deposits on beaches, in shallow seas or in deserts) Grain sorting

How is the sorting of sediments affected by reworking?

Sorting of sediments can also be affected by reworking of the material after deposition, for instance, by winnowing. Well sorted rocks are generally porous, while poorly sorted rocks have low porosity.

What does sorting of sand grains tell you?

This sand is described as fairly well sorted. What is sorting? Very well-sorted sediments – grains all the same size Very poorly-sorted sediments – grains with a wide range of sizes What does sorting tell you? Generally, sediment sorting improves along the sediment transport path.

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