The Formation of Soil (Quiz Questions)
True or false: Climate influences not only the rate of weathering, but the type of native vegetation dominant in an area.
True
True or false: Eluviation of clay, iron, and other materials is the principal process responsible for the formation of an E horizon.
True
True or false: Hydrolysis involves the splitting of water into its hydrogen and hydroxide components while hydration attaches intact water molecules to a compound.
True
True or false: Igneous rocks are formed when molten magma cools and solidifies
True
True or false: Loess is an example of a transported parent material.
True
True or false: Marine sediments are typical parent materials in coastal plain areas.
True
True or false: Organic deposits are most common in areas where water flow over the soil surface is restricted.
True
True or false: Residual parent materials have formed in place and have not been transported from one area to another.
True
True or false: Secondary minerals are recrystallized products of the chemical breakdown and/or alteration of primary minerals.
True
True or false: The A horizons are more apt to be cultivated than the E horizons
True
True or false: The O horizons of a soil are dominantly organic horizons occurring above mineral horizons.
True
The mixed angular gravel, rock, and soil found at the foot of a slope is typical of what type of parent material?
Colluvial
The transformation of gneiss into mica, quartz, and feldspar crystals is an example of ________.
Physical weathering and disintegration
Exfoliation is caused by changes in ________.
Temperature
In which horizon has the process of illuviaton most likely occured?
The B horizon
True or false: Weathering of rocks usually is most intense in the center of a rock fragment, and gradually decreases toward the outside.
False
The element most often involved in oxidation reactions as minerals weather is ________.
Iron
Organic matter accumulation is most pronounced in the ________.
O horizon
True or false: A soil developed in residual parent materials will likely have properties related to the properties of the rock below the C horizon.
True
True or false: Chemical weathering is accelerated by water, oxygen and organic and inorganic acids moving down through the regolith.
True
True or false: Climate influences not only the rate of weathering but the type of native vegetation dominant in an area.
True
True or false: Effective precipitation is a measure of the amount of water that flows into and through the soil profile.
True
True or false: Lacustrine parent materials have been subject to weathering for shorter periods of time than residual parent materials nearby
True
True or false: Residual parent materials have generally been subjected to weathering for a longer period of time than have lacustrine or alluvial parent materials.
True
True or false: Sapric and fibric are terms used to describe peat parent materials.
True
True or false: The depth of a soil profile is dependent on the type of parent material. The more easily weathered the parent material, the deeper the soil profile.
True
If you wanted to find a soil where physical weathering dominated over chemical breakdown you would be most apt to find it in ________.
A desert region of Arizona
The presence of rocks such as shale and sandstone indicate the existence of ________.
Ancient seas
Silicate clay accumulation is most common in the ________.
B horizon
True or false: Sandstones are good examples of metamorphic rocks.
False
True or false: Soils developed in wind-blown parent materials such as loess are generally of little agricultural value.
False
True or false: The C horizons are generally more completely weathered than the other horizons.
False
True or false: The depth of a soil profile is dependent on the climate. Cold dry conditions promote rapid weathering and consequently soils developed under these conditions are deeper than soil developed under wet and warm conditions.
False
True or false: The factors of soil formation act remarkably independent, with little interaction, thus creating similar soils.
False
True or false: The parent materials for most coastal plain soils are residual in nature.
False
True or false: The presence of iron in a mineral generally increases its resistance to chemical breakdown.
False
True or false: The rate of chemical weathering is affected very little by the downward movement of water, oxygen, and organic and inorganic acids flowing through the soil profile.
False
True or false: The topmost horizon in most humid region forest soils is the A horizon.
False
True or false: Tropical forests protect the soil from excessive weathering.
False
Igneous, sedimentary, and metamorphic are three ________.
Types of rocks
Secondary minerals are most prominent in the _______ fraction of soils.
Clay
True or false: A soil developed in transported parents will likely have properties related to the properties of the rock below the C horizon
False
True or false: Alluvial parent materials are those that have been laid down in former lake bottoms.
False
True or false: Animals, microorganisms and plants contribute carbon dioxide to the soil atmosphere. Although the CO2 reacts with water to form carbonic acid, the resulting product has little effect on chemical weathering.
False
True or false: Even if all the glaciers present today in the world were to melt, the melt water would have no measurable effect on the level of the world's oceans.
False
True or false: Glacial till can be recognized by the distinct layering of different kinds of particles.
False
True or false: Glacial till is laid down by melt waters gushing out from the front of glaciers
False
True or false: In a typical weathering sequence, rocks break down into secondary minerals which further undergo physical and chemical weathering to form primary minerals.
False
True or false: In general, alluvium is not good for agriculture
False
True or false: In most B horizons one of the dominant processes of soil formation has been eluviation
False
True or false: Iron and aluminum oxides are major components of igneous rocks.
False
True or false: Living organisms affect soil formation primarily by their constraining the level of oxygen in the soil.
False
True or false: Organic deposits are rarely found in areas of extreme wetness or extreme cold.
False
True or false: Till and outwash are both examples of parent materials readily found in North Carolina
False
True or false: Urban soils generally contain no organic matter, but may have bits of broken glass and other human debris.
False
Which mineral is most resistant to weathering under humid temperate conditions?
Gibbsite
The reaction: Mica + Water -> Potassium + Hydroxide + acid clay is an example of _______.
Hydrolysis
Granite is an example of an _______.
Igneous rock
Residual parent materials are best described as ________.
Materials formed by weathering of rocks and minerals in place
Of the following, which is not a secondary mineral? (Hematite, gypsum, calcite, silicate clay, microcline)
Microcline
Igneous rocks can be best characterized as ________.
Rocks formed when molten magma solidifies
Alluvial fans are usually characterized by ________ soils.
Sandy and gravelly
Biotite -> clay -> iron oxide represents a _________.
Weathering sequence
Glacial till is a term used to describe parent materials that ________.
contain a heterogeneous mixture of mineral debris dropped by receding glaciers
Mechanical weathering processes result in ________.
the disintegration of rocks due to differential expansion of minerals
