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

1.
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Clay minerals formed from gabbro or diorite bedrock illustrate which kind of weathering?
- A.
  Chemical
- B.
  Proactive
- C.
  Syntropical
- D.
  Mechanical
2.
Why is the humus layer typically thicker in a cool, temperate forest soil than in a tropical rainforest soil?
- A.
  Less humus is produced in the tropical rainforest because the B-horizon is so poorly developed
- B.
  Less humus is produced in the cool, temperate forest but the rate of decay and oxidation is slower than in a tropical rainforest.
- C.
  More humus is produced in the tropical rainforest but it is quickly washed away by the heavy rains
- D.
  In a tropical rainforest, the forest-floor litter is offen burned during the dry season
3.
Frost wedging is the majojr weathering process contributing to the formation of which regolith material?
- A.
  Tropical literates
- B.
  Talus slopes
- C.
  C soil horizons
- D.
  Mature pedalfers
4.
What portion of an angular fracture-bounded granitic block shows the highest rate of weathering?
- A.
  The unfractured interior
- B.
  The edges and corners
- C.
  The crack surfaces not including edges and corners
- D.
  All of the above show equal rate
5.
Which of the following describes a characteristic process in the formation of a pedalfer soil?
- A.
  Soil bacteria produce organic acids that precipitate calcium carbonate in the B-horizon
- B.
  Iron oxides and aluminum-rich clays are precipitated in the B-horizon
- C.
  Humus accumulates below the solum in the C-horizon
- D.
  Clays are eluviated upward from the C-horizon
6.
Ln theRockyMountain regionof the United States,north-facingslopes(downhill directionis toward the north)aretyPicallymore moist and heavilyforested than south-facingslopes.Why?
- A.
  A) north-facing slopesreceivemoresunlightin the summer;snow meltsfaster and moresoilmoisture is availablefor thetrees
- B.
  B)south-facingslopesreceivemoremoisfureandstrnlight;rock weatheringis slower
- C.
  North-facingslopesreceive about thesameamountof precipitationassouth-facingslopes;lessmoisture evaporatesfrom north-facingslopes
- D.
  South-facingslopesreceive less moisture, yetrockweatheringis faster
7.
Clayminerals,silica(SiO2),and dissolved potassium bicarbonatein the soil waterareproductsof which process?
- A.
  Chemicalweatheringof olivine and plagioclase feldspar
- B.
  Mechanicalweatheringof graniteandrhyolite
- C.
  Chemicalweatheringof orthoclase feldspar
- D.
  Differentialmechanical weathering of micas
8.
What two factorsspeedup ratesof chemical reactionandrveatheringin rocks and soils?
- A.
  Low temperatures; very dry
- B.
  Low temperatures;very moist
- C.
  High temperatures; very dry
- D.
  warm temperatures; very moist
9.
In terrain with steephill slopes,which crop and cultivation technique will minimize soil erosion?
- A.
  Corn; rows trending straight down the slope,frequent cultivation
- B.
  Apples;land between the treesis planted in grass and not cultivated
- C.
  Winterwheat;after the harvest,thefieldis plowed and left idle until next fall
- D.
  Bean,rows are sPaced wider thanon a levelfield
10.
From the land surface downward to the unweathered bedrock, which of the following is the correct order of the different soil horizons?
- A.
  0, A, E, B, C,bedrock
- B.
  A, B,C,D, E, bedrock
- C.
  E, A, B,C,0, bedrock
- D.
  D, E, C, B, A, bedrock
11.
Whictr one of the following statements concerning mechanical weathcring is not true?
- A.
  Reduces grain sizes of rock particles
- B.
  Allows for faster rates of chemical weathering
- C.
  Is important in the formation of talus slopes
- D.
  Involves a major change in the mineral composition of theweatheredmaterial
12.
The finely divided,red,brown, and yellow soil-coloringmineralsoriginateby what process?
- A.
  Mechanical weathering of very fine-grained,blue-gray clays
- B.
  Chemical weathering of quartz and feldspars
- C.
  Precipitation of iron oxides during the chemical weatheringprocess
- D.
  Mechanical weathering of the feldspars and micas in granit and rhyolite
13.
Wnicn term describes a soil formed by weathering of the underlying bedrock?
- A.
  Transformational
- B.
  Residual
- C.
  Relict
- D.
  Transported
14.
Which of the following best describes the,DustBowl',?
- A.
  The long drought preceding the Irish potato famine of the 1840s
- B.
  The area covered by volcanic ash around Mt. pinatubo,1991
- C.
  Areas of severe wind erosion on the creat plains,1930s
- D.
  A New Year's Day invitational soccer match in Tripoli, Libya
15.
which of the followingis an important, mechanical weathering process for enlarging fractures and extending them deeper into large boulders and bedrock?
- A.
  Oxidation
- B.
  Eluviation
- C.
  Hydrologic cycling
- D.
  Fros twedging
16.
Which of the following bes tdescribes sets of fractures in relatively fresh bedrock,suchasgranitc,that are roughly parallel to the land surface?
- A.
  Thermal expansion cracks
- B.
  Sheetingfractures
- C.
  Hydrolytic failures
- D.
  Columnar joints
17.
Assume that water filling a crack in a rock undergoes cycles of freezing and melting. Which of the following statement is true?
- A.
  water expands as it melts,causing the crack walls to bepushedapart
- B.
  Water shrinks asit freezes,causing thecrack walls to bedrawn closer together
- C.
  water expands asit freezes,causing the crack walls to bepushedapart
- D.
  Water shrinks asit melts,causingthecrackwallsto bep.,it.a closertogether
18.
Which one of the following statements best describes erosion?
- A.
  disintegration and decomposition of rocks and minerals at the surface
- B.
  Movement of weathered rock and regolith toward the base of a slope'
- C.
  The process by which weathered rock and mineral paricles are removed from one area and transported
- D.
  The combined processes of leaching, eluviation,and mass wasting
19.
Quartz weathers readily to aluminum-rich clav minerals.
- A.
  True
- B.
  False
20.

Abundant moistureand warm temperafures result in high ratesof chemical weathering.
- A.
  True
- B.
  False
21.
Feldspars commonly decompose during weathering to clayminerals,silica,andsolubleconstituents.
- A.
  True
- B.
  False
22.
Humus is a concentration of decaying,organicmatter in theB-horizonsof lateritic soils.
- A.
  True
- B.
  False
23.
Calcite,a majorcomPonentof some monumental and building stones,slowlv dissolvesin weaklyacidic waters.
- A.
  True
- B.
  False
24.
Like most otherliquids,water decreasesin volumewhen it freezes.
- A.
  True
- B.
  False
25.
Cemical weathering in bedrock below the land surface often begins along joints and sheeting fractures.
- A.
  True
- B.
  False

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

What portion of an angular, fracture-bounded granitic block shows the highest rate of weathering? The edges and corners.

Where do angular blocks experience most weathering?

Angular blocks, experience the most weathering along their edges and corners. leads to the formation of rounded or spheroidal boulders. One of the minerals most resistant to weathering is this.

What weathering forms large cracks in granite?

Solid rock, like this granitic outcrop on Mount San Jacinto in southern California, fractures into blocks by forces of mechanical weathering. Every day, water seeps into cracks in the granite. Every night the cracks expand as the water freezes. Then, the next day, water trickles further into the expanded crack.

What happens to granite during weathering?

Quartz grains may be eroded, becoming sediment. The quartz in granite is sand- sized; it becomes quartz sand. The quartz sand will ultimately be transported to the sea (bed load), where it accumulates to form beaches. Clays will ultimately be eroded and washed out to sea.