What is the onion skin weathering?

Answer 1

Common in exposed granite, it is the exfoliation of the outer layer of the rock due to differences in temperature between the surface and the interior of the rock which eventually leads to fracturing. This happens when a rock is repeatedly heated and cooled. As it is heated , the outer layer of the rock expands slightly and as it cools the rock contracts. Continual expansion and contraction causes small pieces of the rocks surface to peel off just like a skin of an onion Onion skin weathering can also occur from the dissolution of feldspars in granite rock by acidic rainfall, which creates clay minerals. The outer layer of a chemically weathered granitic rock can become crumbly and slough off in layers, typical of onion skin weathering.

Answer 2

Onion skin weathering is when a top layer of rock gets extremely hot, but then meets a sudden drop in temperature, then the top layer of the rock splits and flakes away. For example take a piece of granite and heat over a blue flame on a Bunsen burner, till the rock starts to turn red, then dunk the rock into a beaker of !cold! water, and it should crumble, if its hot enough.

That's why stones in the desert are so small and the floor is so cracked.

Answer 3

The outer surface of the body of rock is attacked first by the agents of weathering and becomes separated from the main body of the rock. Depressurization is also a factor in large rock bodies as they are uplifted by tectonic forces or erosion of the material above them. As the pressure from the material that surrounds them is removed, the outer surface rock becomes detached from the main rock body.

Answer 4

In a desert where it is warm during the day and cold at night

Answer 5

In a desert. Onion -skin weathering only occurs where it is warm in the day, and cold at night. This happens, because when the rock gets hot, it expands, and when it gets cold, it contracts.