Which of the following is NOT a type of weathering process?

The chosen answer highlights that hydraulic weathering is not typically classified as a standard type of weathering process. In the study of geology and weathering processes, commonly recognized types include biological, chemical, and physical weathering.

Biological weathering occurs when organisms, such as plants or animals, contribute to the breakdown of rocks and minerals, often through physical actions like root growth or the production of organic acids. Chemical weathering involves the chemical alteration of minerals, leading to changes in rock composition, such as oxidation or hydrolysis. Physical weathering, also known as mechanical weathering, refers to the disintegration of rocks without any chemical change, often due to processes like freeze-thaw cycles, where water seeps into cracks, freezes, and expands, causing the rock to break apart.

While the term "hydraulic weathering" is sometimes used informally to refer to water's role in weathering processes (especially in hydraulic action), it is not widely accepted as a distinct category on the same level as the other three. Therefore, recognizing hydraulic weathering as an unstandardized term highlights its absence from the conventional classification of weathering types.