Why do sedimentary deposits tend to become smaller-grained and better sorted wit

Question

Why do sedimentary deposits tend to become smaller-grained and better sorted with greater distance from their source? Select one: a. Small sediments are usually found closest to the source area because they are too light to be transported far, while larger sediments such as silt and clay travel the farthest 0 ? b. They don't! ?.urge sediments are usually found closest to the source area because they are too heavy to be transported far, while smaller sediments such as silt and clay travel the farthest. d.

Explanation / Answer

Answer: Correct answer is option c.

c. Large sediments are usually found closest to the source area because they are too heavy to be transported far while smaller sediments such as silt and clay travel the farthest.

The answer is self explanatory but we can understand this with respect to a natural setting. Imagine a river that cuts a mountain. Due to erosion by the flow of the river, the parent rock breaks away. The heavier boulders cannot be carried by the current of the river and hence deposit closer to where the river originates while smaller rocks are carried in the river current. Over a particular length and depending on how strong the river current is, the comparatively lighter rock fragments (which will be gravel sized) will be deposited next followed by even smaller particles of sand, silt and finally clay (the finest particles of them all). The answer given above is correct but do understand that if there is a change in the strength of the river current, there may be a change or irregularity in the size of the sediments deposited.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.