What is the Difference Between Abrasion and Attrition

The main difference between abrasion and attrition is that abrasion is a slow process, whereas attrition is a fast process.

Abrasion and attrition are two geological processes, and these terms have applications in earth sciences. Both abrasion and attrition refer to the process of erosion, but there is a difference between abrasion and attrition according to the rate of erosion.

Key Areas Covered

1. What is Abrasion 
     – Definition, Characteristics
2. What is Attrition
     – Definition, Characteristics
3. What is the Difference Between Abrasion and Attrition
     – Comparison of Key Differences

Key Terms

Abrasion, Attrition, Erosion

What is Abrasion

Abrasion is a type of erosion where the material being transported erodes away at a surface over time. This means the process of abrasion is a slow erosion. The possible cause for abrasion is the friction caused by scuffing, scratching, wearing down, marring, rubbing away, etc. The intensity of this process is determined by the hardness, concentration, velocity, and mass of the material that is being eroded. In contrast to attrition, abrasion usually occurs due to the rubbing of the surface against each other, which results in wearing down of one surface or both surfaces.

Generally, the process of abrasion occurs in four major ways: glaciation, coastal erosion, channel transport, and from the wind. Glaciation slowly grinds rocks picked up by ice against rock surfaces. In channel transport abrasion, the surfaces of solid objects that travel through river channels cause erosion. Coastal erosion is the abrasion caused by objects flowing in water due to waves. The final method of abrasion is the abrasion caused by sand and small stones transported by the wind.

What is Attrition

Attrition is a type of erosion which occurs very fast in comparison to abrasion. Generally, we consider it as a coastal or river erosion. During attrition, we can observe that the objects travelling through a river channel downstream can hit the river bed materials and break down the bed material into very small to medium fragments.

During this process, the newly produced bed particles become round and smooth. Unlike in abrasion, where the rubbing of surfaces causes the erosion, attrition refers to hitting of surfaces which cause erosion. We can also observe attrition in glacial regions, where abrasion takes place due to the movement of ice with embedded boulders over surface sediments.

The intensity of attrition depends on various factors, including the particle properties such as size, shape, surface, porosity, hardness, and cracks. Moreover, some environmental factors, such as time, velocity, pressure, shear, and temperature, affect the rate of attrition. At the upstream of a river, there is a great velocity. Therefore, the particles at this region are more affected than the particles downstream.

Difference Between Abrasion and Attrition

Definition

Abrasion is a type of erosion where the material being transported erodes away at a surface over time while attrition is a type of erosion which occurs very fast compared to abrasion.

Rate

Abrasion is a slow process, while attrition is a fast process.

Reason

Moreover, rubbing of surfaces causes abrasion while hitting of surfaces causes attrition.

Factors Affecting the Process

Factors like hardness, concentration, velocity, and mass of the material subject to erosion affect abrasion while particle properties such as size, shape, surface, porosity, hardness, and cracks and some environmental properties affect attrition.

Conclusion

Both abrasion and attrition refer to the process of erosion, but they differ from each other according to the rate of erosion. The main difference between abrasion and attrition is that abrasion is a slow process, whereas attrition is a fast process. Moreover, abrasion occurs due to the rubbing of the surface, which causes one or both surfaces to undergo erosion. In contrast, attrition occurs due to the hitting of one surface another.

Reference:

1. “Abrasion (Geology).” Wikipedia, Wikimedia Foundation, 20 May 2020, Available here.
2. “Attrition (Erosion).” Wikipedia, Wikimedia Foundation, 22 Apr. 2020, Available here.

Image Courtesy:

1. “Glacial-abrasion-ss-2006” By – Siim assumed – No machine-readable source. Own work assumed (based on copyright claims) (CC BY-SA 3.0) via Commons Wikimedia
2. “Haast River 14” By Krzysztof Golik – Own work (CC BY-SA 4.0) via Commons Wikimedia