Weathering of Rocks Quiz

The breakdown of rock into smaller pieces on Earth's surface.

The physical breakdown of rock without changing its chemical makeup.

A process where water seeps into cracks, freezes, expands, and breaks the rock.

The wearing away of rocks by friction and impact from other rocks or particles.

A pile of broken rock pieces formed by frost wedging.

Small pieces of rock or mineral that result from weathering.

The process of altering rock by changing its chemical composition.

A place where rocks are found.

Minerals dissolving in water forming a solution.

Water reacting with minerals to form new minerals.

Minerals reacting with oxygen to form new compounds.

Salt crystals growing and expanding in cracks, causing rocks to break.

Rocks expanding when heated and contracting when cooled, eventually causing cracks.

Water with a pH level outside neutral range, dissolves minerals more rapidly.

A weathering process that happens to iron-bearing rocks.

A chemical created when sulfide minerals oxidize during weathering.

Weathering caused by plants and fungi that disolves minerals.

The process of moving sediment from the source to its deposition spot.

Soil removal and transportation by wind.

Soil will NOT accumulate indefinitely; erosion keeps it at a stable thickness.

Rocks formed from compressed and cemented sediments.

Water is the most common agent of erosion. It carries millions of tons of sediment daily through rivers, coasts, and oceans.

The rolling or dragging of large grains aided by push or large drains.

The bouncing of sand grains as they are picked up, carried along, and dropped repeatedly.

Movement of fine particles like silt and clay.

Rivers form distributary channels, which are branches that spread out and deposit sediments, forming tidal flats.

Areas of land formed by the deposition of sediments from rivers entering the sea.

The downslope movement of rocks, soil, or any earth material, primarily due to gravity.

A type of mass wasting where fine-grained materials like clay and silt move downhill, often triggered by heavy rains or snowmelt. It typically forms narrow, tongue-like features starting from a cliff or scarp.

A type of mass wasting involving the movement of dry or nearly dry granular materials like sand, primarily driven by gravity. Commonly observed on dunes, where sand flows down the face.

A high-velocity mass wasting event involving a massive amount of falling rocks and debris. The impact pulverizes the material and can be triggered by steep slopes in mountainous regions.

Several factors can initiate mass wasting, including:

• Shocks and vibrations: Earthquakes, explosions, or heavy traffic can shake slopes and destabilize them.
• Slope modification: Changing the slope angle, making it steeper than its natural angle of repose, can increase instability.
• Undercutting: Erosion by rivers or waves can undercut a slope, making it more prone to collapse.
• Hydrologic changes: Heavy rains or snowmelt saturate the soil, adding weight and reducing its strength, increasing susceptibility to failure.
• Slope strength changes: Weathering weakens rocks, making them more prone to failure. Vegetation helps stabilize slopes, but removal or damage can create instability.
• Volcanic eruptions: These events can produce shocks and melt glaciers, generating mudflows and debris flows.

Vegetation plays a crucial role in stabilizing slopes by holding the soil in place and slowing the influx of water. Plant roots bind the soil together, providing strength and reducing erosion. However, deforestation or damage to vegetation can make slopes more vulnerable to mass wasting.

The steepness of a slope is a major factor in determining if mass wasting will occur. A steeper slope increases the force pulling material downhill. This force is greater than the force holding the material in place, making it more likely to slide.

Forces resisting movement downslope are collectively called shear strength. It determines how well a slope holds together. This strength depends on factors like friction, cohesion of particles, water pressure, and plant roots.

Water can have a double-edged effect on slope stability. While surface tension can help bind grains together, too much water fills pore spaces, reducing friction between particles and making the slope more likely to fail.

The steepest angle at which a pile of loose material can remain stable without sliding is called the angle of repose. It's influenced by the material's properties and the amount of water present.

Certain types of clay can significantly influence a slope's stability. Expansive clays swell when wet, creating pressure that can destabilize slopes. Sensitive clays lose strength when disturbed.

The steepness of a slope affects its stability. A steeper slope increases the force pulling material downhill, making it more likely to slide.

The force acting parallel to a slope, pushing material downslope.

Water can both increase and decrease slope stability. Some water helps bind grains together, but too much water reduces friction and weakens the slope.

Clays that expand when wet, creating pressure that can destabilize slopes.

Clays that lose strength when disturbed, often due to the dissolution of salts in their pore spaces.

Various factors can initiate mass wasting, such as shocks, slope modification, undercutting, hydrologic changes, and changes in slope strength.