Audio Transcript Excerpt:
PROFESSOR: 'In geomorphology, mass wasting events are categorized based on three parameters: the type of material involved (

Question

Audio Transcript Excerpt:
PROFESSOR: 'In geomorphology, mass wasting events are categorized based on three parameters: the type of material involved (rock versus unconsolidated regolith debris), the velocity of motion (ranging from millimeters per year to hundreds of kilometers per hour), and the physical mechanics of the movement. Under mechanics, we distinguish three primary modes: falls, slides, and flows. A 'fall' involves material detaching and dropping freely through the air down a vertical cliff face. A 'slide' involves a coherent mass moving along a discrete, well-defined planar failure surface. A 'flow,' by contrast, occurs when the internal material behaves as a viscous fluid, with differential internal shearing throughout the mass, usually lubricated by high pore-water pressure.'

How does the professor distinguish a 'slide' from a 'flow' in mass wasting?

Accepted Answer

A slide moves as a coherent block along a distinct failure plane, while a flow undergoes internal fluid shearing throughout the moving mass.

Answer

Slides occur only in winter, whereas flows occur exclusively in volcanic vents.

Answer

Slides consist entirely of dry sand, whereas flows consist exclusively of solid granite bedrock.

Answer

A slide moves vertically through the air, while a flow moves horizontally along a riverbed.

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