Question
click below
click below
Question
Normal Size Small Size show me how
Ch.5 (Final)
Weathering and Soils
Question | Answer |
---|---|
(T/F) The term mechanical weathering refers to changes in a rock that are physical; there is little or no chemical change. | True |
(T/F) Chemical weathering will eventually change a quartz crystal into clay minerals. | False |
(T/F) The reduction of pressure on a body of rock can cause it to crack as it expands. | True |
(T/F) Plants, such as roots growing in cracks, and animals compacting the soil, have little influence on mechanical weathering. | False |
(T/F) Without chemical weathering, the elevated levels of carbon dioxide in the atmosphere would have long ago made the Earth too hot to sustain life. | True |
(T/F) Oxygen is abundant in the atmosphere but it does not combine with minerals of the Earth's crust. | False |
(T/F) An acid is a chemical compound that gives off hydrogen ions (H+) to a chemical reaction. | True |
(T/F) When feldspar is attacked by carbonic acid it forms clay minerals. | True |
(T/F) The single most important agent for the chemical weathering is temperature. | False |
(T/F) The B-horizon in soil is the zone of accumulation. | True |
(T/F) Sand-size grains of feldspar can be preserved in a soil profile over great time periods because of feldspar's resistance to chemical weathering. | False |
___ is the picking up and physical removal of rock particles by an agent such as wind, flowing liquid water, or glaciers. | Erosion |
_______ refers to the group of destructive processes that change the physical and chemical character of rocks at the Earth's surface. | Weathering |
Chemical weathering generally proceeds __. | along contacts between mineral grains |
_______ is a byproduct of rock weathering. | Soil |
Water that has trickled down into a joint in a rock can freeze, expand, and _____. | widen the crack and hastening the rock's disintegration |
Frost wedging is most effective __. | in areas with many days of freezing and thawing |
The removal of a great weight of rock above a batholith by erosion allows the granite to expand forming ______. | sheet joints |
The ____ describes the process in which this dominant greenhouse gas circulates among Earth systems. | carbon cycle |
The most important natural source for the formation of acid for rock weathering at the Earth's surface is dissolved _______. | carbon dioxide |
_______ are commonly left after complete chemical weathering. | Quartz and clay minerals |
What, in terms of Earth systems, forms an essential interface between the geosphere, biosphere, hydrosphere, and atmosphere? | soil |
When feldspar is attacked by carbonic acid it forms _____. | a clay mineral |
_____ is the mineral least susceptible to chemical attack on the Earth's surface. | Quartz |
Olivine weathers rapidly because its isolated silicon-oxygen tetrahedra are held together by _________ ionic bonds to iron and magnesium. | weak |
The _______ horizon is the uppermost layer of a soil; it consists of organic material | O |
The _______ horizon is the dark-colored soil horizon that is rich in organic material and forms just below the surface vegetation | A |
The _____ horizon is the incompletely weathered parent material lying below the B-horizon | C |
As soils mature, distinct layers called ______ appear. | horizons |
Under wet and humid tropical conditions the least soluble material is the aluminum oxide called _____. | bauxite |
A soil formed entirely through the weathering of basalt would not contain sand-sized grains of __. | quartz |
Plants and burrowing organisms contribute to soil development by __. | All of the answers are correct. |