Exam 5: Weathering and Soil

The single most important agent for the chemical weathering is temperature.

_______ refers to the group of destructive processes that change the physical and chemical character of rocks at the Earth's surface.

Ordinary rain has a pH of about 5.5 to 6 from the carbon dioxide in the atmosphere and from natural sources of acidic sulfur gases.

____ tend(s) to weather much faster than sandstone.

When feldspar is attacked by carbonic acid it forms clay minerals.

When fossil fuels are burned _____, enter the atmosphere to form acid rain.

Frost wedging is most effective __.

Chemical weathering generally proceeds __.

Sulfuric acid is produced naturally during __.

The reduction of pressure on a body of rock can cause it to crack as it expands.

The most important natural source for the formation of acid for rock weathering at the Earth's surface is dissolved _______.

The removal of a great weight of rock above a batholith by erosion allows the granite to expand forming ______.

The term mechanical weathering refers to changes in a rock that are physical; there is little or no chemical change.

As soils mature, distinct layers called ______ appear.

The only processes that affect rock are weathering and climate.

Plants and burrowing organisms contribute to soil development by __.

A ___ soil is one that develops from the bedrock directly beneath it.

___ are the most common materials precipitated as cement, which binds loose particles of sand into a solid sedimentary rock.

At the surface of the Earth, ultramafic rocks in kimberlite pipes weather away leaving behind concentrations of _____.

Without chemical weathering, the elevated levels of carbon dioxide in the atmosphere would have long ago made the Earth too hot to sustain life.