Deck 16: Groundwater

Question 1

How do large, spheroidal boulders form from massive bedrock?

A) A fresh rock slab is broken out along sheeting fractures and then rounded by residual laterization.
B) Exfoliation breaks a fresh, spherical block from the bedrock.
C) An angular block, broken away from bedrock, gets rounded by rolling down a slope.
D) The corners and edges of fracture- bounded blocks are weathered faster than the planar areas of the fracture surfaces.

Answer 1

D

Question 2

is the great reduction in pressure from erosion and it leads to the formation of in mountainous exposures of granitic batholiths.

A) Offloading, deep valleys
B) Relief, horns or tinds
C) Flatulence, plateaus
D) Unloading, exfoliation domes

Answer 2

D

Question 3

The finely divided, red, brown, and yellow soil- colouring minerals originate by what process?

A) chemical weathering of quartz and feldspars
B) precipitation of insoluble iron oxides during the chemical weathering process
C) mechanical weathering of very fine- grained, blue- grey clays
D) mechanical weathering of the feldspars and micas in granite and rhyolite

Answer 3

B

Question 4

Under similar warm, moist climatic conditions, why would basalt and gabbro generally have higher chemical weathering rates than rhyolite and granite?

A) The plagioclase feldspars in the granite and rhyolite decompose readily to clay minerals and iron oxides.
B) The potassium feldspars and quartz in the rhyolite and granite are more susceptible to cracking by frost wedging.
C) The quartz in the gabbro and basalt decomposes very quickly.
D) The ferromagnesian minerals in the gabbro and basalt are subject to oxidation and chemical breakdown.

Question 5

Lateritic soils form under what climatic conditions?

A) hot and dry as in the desert regions of North Africa and Arabia
B) cool and relatively dry as in Nunavut
C) moist and temperate as in southwest BC
D) warm and moist as in a wet, tropical forest

Question 6

Caliche is an excessive accumulation of .

A) calcite in the E horizon of a pedalfer
B) clays in hardpan layers of a pedocal
C) calcium carbonate in the B horizon of a pedocal
D) clays in the A horizon of a laterite

Question 7

What chemical weathering process associated with surface mining activities is a major environmental hazard?

A) oxidation of pyrite and other sulphides to produce "mine acid" or acid rock drainage
B) recurrent landslides from unstable talings piles
C) release of oxidized mine gases
D) coal oxidation

Question 8

What is the common soil formed in semi- arid grassland with alkali and salt tolerant plants as in SE Alberta and SW Saskatchewan?

A) solonetzic and pedocal
B) luvisol
C) chernozem
D) cryosol

Question 9

The principal causes of mechanical fragmentation of rocks in place are .

A) the relentless actions of Sisyphus
B) always inscrutable because they happened at some time in the past
C) erosion and transport by moving wind, water, or ice
D) biologic activity, expansion from unloading, frost wedging

Question 10

What mineral particles are the dominant colouring agents in reddish, brownish, and yellowish soils?

A) soluble potassium and sodium bicarbonates
B) dust- sized grains of iron oxides
C) very fine- sized silica and calcite particles
D) humus and calcium carbonate

Question 11

is the dissolution or decomposition of minerals and rocks.

A) Chemical weathering
B) Rendering
C) Mechanical weathering
D) Hydrolysis

Question 12

Where would you be best advised to attempt large scale, natural plantations of a popular

A) Alberta
B) Saskatchewan
C) Manitoba
D) BC or the Maritimes

Question 13

Clay minerals formed from gabbro or diorite bedrock illustrate which kind of weathering?

A) mechanical
B) syntropical
C) proactive
D) chemical

Question 14

The physical removal of dissolved or disaggregated rock from the site of weathering by wind, water, or ice is termed .

A) ablation
B) recidivism
C) erosion
D) solifluction

Question 15

Frost wedging is the major weathering process contributing to the formation of which regolith material?

A) talus slopes
B) tropical laterites
C) lunar soils
D) C soil horizons

Question 16

Which of the following statements concerning humus is false?

A) consists of decaying and partly decayed leaves and other plant materials
B) is less abundant in wet, tropical, forested areas than in temperate, forested areas
C) is readily leached from the B horizon in weakly acidic, soil solutions
D) is typically found above the B soil horizon

Question 17

What two factors speed up rates of chemical reaction and weathering in rocks and soils?

A) warm temperatures; very moist
B) low temperatures; very dry
C) high temperatures; very dry
D) low temperatures; very moist

Question 18

What is represented by the A, E, B, and C soil horizons in luvisol, podsol, or chernozem?

A) multiple caliche horizons
B) buried humus layers
C) an in situ response to an extended period of weathering
D) primary, depositional layering in a transported soil

Question 19

are regularly spaced planar fracture sets in rocks that result from: expansional unloading, tectonic forces, or thermal contraction upon cooling (especially igneous rocks).

A) Joints
B) Faults
C) Cracks
D) Fissures

Question 20

Which of the following is/are most susceptible to chemical weathering by dissolution?

A) iron oxides
B) calcite
C) quartz
D) clay minerals

Question 21

Which of the following best describes the process of eluviation?

A) buildup of calcite in the B horizon of pedocal soils
B) removal of soluble chemical constituents from the A and B soil horizons
C) Percolating water removes very fine- sized silt and clay particles from the A and E soil horizons.
D) feldspar decomposition and leaching of the soluble products from the C soil horizon

Question 22

Which of the following statements about acidic precipitation is false?

A) Fish and other aquatic species in acidified lakes will eventually die off and disappear due to the toxic effects of the acidic waters and increased levels of dissolved aluminum.
B) Damage to trees and plants, especially to tender new growth, will intensify if acidic precipitation worsens.
C) Chemical weathering and deterioration of exposed rock and metal surfaces will accelerate if acidic precipitation increases.
D) Acid precipitation from industrial sources has almost been eliminated and is no longer a concern for the environment.

Question 23

In which of the following climates would rates of chemical weathering generally be highest?

A) warm and moist
B) cold and moist
C) cold and dry
D) warm and dry

Question 24

Dissolution of minerals occurs because most minerals are ionic crystals and .

A) water selectively absorbs all of their electrons until the crystals fall apart
B) water selectively removes all of their smaller anions
C) their bonds eventually wear out
D) water molecules are strongly polarized, effectively competing with ionic bonds

Question 25

Which one of the following is an important, mechanical weathering process for enlarging fractures and extending them deeper into large boulders and bedrock?

A) frost wedging
B) eluviation
C) oxidation
D) hydrologic cycling

Question 26

Why is the humus layer typically thicker in a cool, temperate, forest soil than in a tropical rainforest soil?

A) In a tropical rainforest, the forest- floor litter is often burned during the dry season.
B) Less humus is produced in the tropical rainforest because the B horizon is so poorly developed.
C) More humus is produced in the tropical rainforest, but it is quickly washed away by the heavy rains.
D) Less humus is produced in the cool, temperate forest but the rate of decay and oxidation is slower than in a tropical rainforest.

Question 27

What is the common soil formed in moist, temperate areas like most of Quebec and the Maritimes?

A) pedalfer (podzol)
B) chernozem
C) cryosol
D) luvisol

Question 28

Clay minerals, silica (SiO2), and dissolved potassium bicarbonate in the soil water are products of which process?

A) mechanical weathering of granite and rhyolite
B) chemical weathering of olivine and plagioclase feldspar
C) differential mechanical weathering of micas
D) chemical weathering of orthoclase feldspar

Question 29

Which of the following affects both the kind of soil and its rate of formation?

A) meteorite showers
B) type of vegetation cover
C) sun spot activity
D) plants and animals, climate, and parent material

Question 30

Hydrolysis is to weaken or destroy the mineral lattice.

A) the replacement of mineral cations by hydrogen ions from solution
B) the conversion of useless minerals to hydrogen gas
C) the chemical removal of bonded hydrogens
D) the dissolution of minerals by water

Question 31

Which of the following best describes the A soil horizon?

A) leaching zone
B) residual zone
C) regolith zone
D) erosion zone

Question 32

How long do the acid generating gases from fossil fuel combustion remain in the lower levels of the atmosphere and how far do they travel?

A) weeks to months; only locally
B) less than a few hours; a few kilometres
C) several years; around the world
D) a few hours to a few days; up to several thousand kilometres

Question 33

Which one of the following statements is false?

A) Mechanical weathering reduces grain sizes of rock particles.
B) Mechanical weathering allows for faster rates of chemical weathering.
C) Mechanical weathering involves a major change in the mineral composition of the weathered material.
D) Mechanical weathering is important in the formation of talus slopes.

Question 34

Which of the following best explains why angular, crack- bounded, granitic blocks weather to spheroidal boulders?

A) Crack surfaces of blocks heat and cool more rapidly than edges and corners.
B) Interiors of blocks are constantly damp or wet because sunlight cannot penetrate.
C) Weathering agents have more direct access to edges and corners than to other parts of the block.
D) They slowly roll over in place and wear off the corners first.

Question 35

Which term describes a soil formed by weathering of the underlying bedrock?

A) transubstantiated
B) residual
C) transported
D) relict

Question 36

Assume that water filling a crack in a rock undergoes cycles of freezing and melting. Which of the following statements is true?

A) Water shrinks as it freezes, causing the crack walls to be drawn closer together.
B) Water expands as it freezes, causing the crack walls to be pushed apart.
C) Water shrinks as it melts, causing the crack walls to be pulled closer together.
D) Water expands as it melts, causing the crack walls to be pushed apart.

Question 37

As increases the surface area of a rock or mineral, this allows to occur at a faster rate.

A) infernal weathering, mechanistic weathering
B) recrystallization, carnal weathering
C) mechanical weathering, chemical weathering
D) chemical weathering, mechanical weathering

Question 38

What oxidized iron bearing minerals generally form as the residue of weathering?

A) ferrous feldspars
B) goethite, hematite, and limonite
C) olivine, pyroxene, and amphibole
D) pyrite and native iron

Question 39

Which of the following statements about laterites or tropical rainforests is true?

A) Laterites, with proper management, are very suitable for commercial agriculture.
B) Laterite soils readily compact and harden when dried and exposed to sunlight.
C) Laterite soils are very rich in nutrients required for vigorous plant growth.
D) Rainforests regenerate quickly following clear cutting or clearing for agriculture.

Question 40

Which of the following best describes the "Dust Bowl"?

A) a New Year's Day invitational soccer match in Tripoli, Libya
B) the area covered by volcanic ash around Soufriere Hills in 2010
C) areas of severe wind erosion on the Prairies, 1930s
D) the long drought preceding the Irish potato famine of the 1840s

Question 41

Which is the common soil formed in dry young forest with long winters as in Yukon?

A) brunisol
B) cryosol
C) podzol
D) gleysol

Question 42

Which would make the longest lasting headstone for Granny's grave in "Peaceful Acres" on the east side of Toronto?

A) a pink Precambrian quartzite
B) a polished, fine grained basalt
C) a large rough limestone slab from a quarry near Kingston
D) a coarse- grained grey granite

Question 43

Which one of the following statements is the best description of erosion?

A) disintegration and decomposition of rocks and minerals at the surface
B) the process by which weathered rock and mineral particles are removed from one area and transported elsewhere
C) movement of weathered rock and regolith toward the base of a slope
D) the combined processes of leaching, eluviation, and mass wasting

Question 44

In which area would weathering by frost wedging probably be most effective?

A) in moist, temperate climates
B) in cool, high desert areas
C) where the subsoil is permanently frozen
D) in a moist, tropical forest

Question 45

What portion of an angular, fracture- bounded granitic block shows the highest rate of weathering?

A) the middle of faces bounded by a single large fracture
B) the exposed edges and corners
C) the crack surfaces not including edges and corners
D) the unfractured interior

Question 46

The downslope transfer of loose rock and soil particles by the force of gravity is called .

A) mass migration
B) slopewash
C) mass wasting
D) gravity

Question 47

is the most common mineral breakdown product of KAlSi3O8 (potassium feldspar).

A) Asbestos
B) Kaolinite
C) Calcite
D) Quartz

Question 48

Ordinary chemical weathering of rock forming minerals like feldspar and amphibole produces

A) dissolved clays and iron hydroxides
B) soluble silica and ions (Ca+2 , Na+ , Mg+2 ) plus residues of clay minerals
C) all of the sodium and chloride ions that make the salt content of the seas
D) solid residues of quartz and reduced iron compounds

Question 49

In which area are pedocal soils most likely to be found?

A) a bitterly cold, permafrost area in north- central Siberia
B) a moderately dry to semiarid grassland such as SW Saskatchewan
C) a tropical rainforest in the Amazon Basin of Brazil
D) a forested area of SE Manitoba

Question 50

From the land surface downward to the unweathered bedrock, which of the following is the correct order of the different soil horizons?

A) E, A, B, C, O, bedrock
B) A, B, C, D, E, bedrock
C) O, A, E, B, C, bedrock
D) D, E, C, B, A, bedrock

Question 51

What two chemical constituents cannot form by chemical weathering of the feldspar minerals alone?

A) insoluble iron oxides and soluble magnesium bicarbonates
B) soluble sodium and potassium bicarbonates
C) silica and soluble calcium bicarbonate
D) silica and insoluble clay minerals

Question 52

Which term best describes an accumulation of angular rock fragments at the base of a steep, bedrock slope or cliff?

A) bajada
B) fanglomerate
C) talus slope
D) rock and roll

Question 53

The three major processes involved in chemical weathering are .

A) carbonation, dissimulation, and salinization
B) recrystallization, pitting, and rinsing
C) precipitation, ion exchange reactions, and degasification
D) dissolution, hydrolysis, and oxidation

Question 54

Which of the following best describes sets of fractures in relatively fresh bedrock, such as granite, that are roughly parallel to the land surface?

A) sheeting fractures
B) columnar joints
C) hydrolytic failures
D) thermal expansion cracks

Question 55

Which term best describes those processes that move weathered rock materials and soils downslope?

A) slope sheeting
B) mass wasting
C) talus transfer
D) podzolization

Question 56

Which of the following statements concerning lateritic soils is generally false?

A) They remain highly productive agriculturally without additions of fertilizers.
B) They consist of only the most insoluble, soil- forming minerals such as iron oxides, aluminum oxides, and clays.
C) They form in warm, moist, tropical climates.
D) They are mainly red in colour.

Question 57

In nature, where does the acidity come from to speed up chemical weathering?

A) plutonism
B) Bowen's reaction series
C) nuee ardentes from explosive volcanic eruptions
D) organic acids from decayed plants, acid rain, and sulphuric acid from oxidation of pyrite

Question 58

Which of the following describes a characteristic process in the formation of a pedalfer soil?

A) Humus accumulates below the solum in the C horizon.
B) Soil bacteria produce organic acids that precipitate calcium carbonate in the B horizon.
C) Clays are eluviated upward from the C horizon.
D) Iron oxides and aluminum- rich clays are precipitated in the B horizon.

Question 59

Which are examples of Earth's external processes?

A) erosion, weathering, and mass wasting
B) volcanism and mountain building
C) radioactive decay, convection, and recrystallization
D) compaction, dewatering, and cementation of sediments

Question 60

Which one of the following statements concerning soil erosion is false?

A) Grasses and other vegetation, windbreaks, and contour cropping will help reduce losses of soil from cultivated lands.
B) Soils form naturally by weathering; if protected from erosion, sound management can maintain or enhance their nutrient levels and textural characteristics.
C) Sheet erosion, rills, and gullies develop mainly during prolonged droughts.
D) Rates of soil erosion exceed rates of soil formation in some parts of the world.

Question 61

What is the term for the selective removal of softer or less stable portions of a rock?

Question 62

Compare and contrast soil formation between an arid region underlain by quartz sandstone and a temperate climate in an area composed of granite.

Question 63

List the major processes that contribute to chemical weathering.