Geol Test 2

  1. Which of the following is/are most susceptible to chemical weather by dissolution?

    A. calcite
  2. Frost wedging is the major weathering process contributing to the formation of which regolith material?

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

    D. chemical weathering of orthoclase feldspar
  4. What two factors speed up rates of chemical reaction and weathering in rocks and soils?

    D. warm temps; very moist
  5. In which area are pedocal soils mostly likely to be found?

    D. a moderately dry to semiarid grassland such as the western Great Plains
  6. The finely divided, red, brown, and yellow soil-coloring minerals originate by what process?

    B. precipitation of iron oxides and during the chemical weathering process
  7. Which of the following statements about laterites or tropical rainforest is true?

    A. laterite soils readily compact and hardened when dried and exposed to sunlight
  8. Which one of the following is an important, mechanical weathering process for enlarging fractures and extending them deeper into large boulder and bedrock?

    A. frost wedging
  9. 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
  10. under similar war, moist climatic conditions, what would basalt and gabbro generally have higher chemical weathering rates than rhyloite and granite?

    A. the ferromagnesian minerals in the gabbro and basalt are subject to oxidation and chemical weathering
  11. Which one of the following statements concerning mechanical weathering is not true?

    C. involves a major change in the mineral composition of the weathered material
  12. Which one of the following statements best describes erosion?

    C. movement of weathered rock and regolith toward the base of a slope
  13. Assuming that water filling a crack in a rock undergoes cycles of freezing and melting. Which of the following statements is true?

    A. water expands as it freezes, causing the crack walls to be pushed apart
  14. What mineral particles are the dominant coloring agent in reddish, brownish, and yellowish soils?

    A. dust-sized grains of iron oxides
  15. Lateritic soils form under what climatic conditions?

    A. warm and moist as in the wet, tropical forest
  16. ____, a common mineral found in igneous rocks, is the most abundant mineral in detrital sedimentary rocks.

    C. quartz
  17. Sandstone (Match the sediment with the appropriate rock name.)

    B. sand
  18. Shale (Match the sediment with the appropriate rock name.)

    C. all clay sediment
  19. Mudstone (Match the sediment with the appropriate rock name.)

    C. clay and fine silt
  20. Conglomerate (Match the sediment with the appropriate rock name.)

    B. gravel
  21. Which of the following best describes bedded gypsm and halite?

    C. evaporates; chemical, sedimentary rocks
  22. ____ sandstone contains abundant feldspar, suggesting that the sand was derived by weathering and erosion of granitic bedrock.

    C. arkosic
  23. What is the main difference between a conglomerate and a sedimentary breccia?

    D. breccia clasts are angular; conglomerate clasts are rounded
  24. Which statement concerning sedimentary rocks is not true?

    B. they were originally deposited at depth below the bottom of the sea
  25. ____ is not a common cementing agent for sandstones.

    D. fluorite
  26. Which of the following applies to the basic constituents of halite, gypsum, and sylvite?

    C. transported as dissolved ions; deposited by evaporation
  27. Flint, chert, and jasper are microcrystalline forms of ____

    D. quartz
  28. Which of the following sedimentary rocks would you expect to have originally been deposited by fast-moving streams?

    A. conglomerate
  29. Detrital grains of which minerals are extremely rare in detrital sediments? Why?

    A. calcites; it is soft and relatively soluble
  30. Which of the following sedimentary features would typically be found in shales but not in sandstones?

    A. mudcracks
  31. ____ is the most common type of chemical sedimentary rock.

    C. limestone
  32. Which of the following sedimentary features can each be used to determine paleocurrent directions?

    B. ripple marks and cross stratification
  33. Coal beds originate in -

    D. freshwater costal swamps and bogs
  34. Which of the following forms is at the highest grade of regional metamorphism?
    a. schist
    b. hornsfel
    c. phyllite
    d. slate
  35. What platy, parallel, mineral grains are the most visual aspect of foliated metamorphic rocks?

    D. micas
  36. What major change occurs during metamorphism of limestone to marble?

    A. calcite grains grow larger and increase in size
  37. Which low-grade metamorphic rock, composed of extremely fine-sized mica and other mineral grains, typically exhibits well-developed rock cleavage?

    A. slate
  38. _____ is a strong, parallel alignment of coarse mice flakes and/or of different mineral bands in a metamorphic rock.

    D. foliation
  39. Which of the following best describes the conditions of contact metamorphism?

    A. pressures are fairly low, the rock is in the upper part of the crust, and heat is supplied from a nearby magma body
  40. ____ forms from the metamorphism of limestone or dolostone

    D. marble
  41. ___ is characterized by segregation of light-and dark-colored minerals into thin layers or bands.

    B. granitic gneiss
  42. Which of the following lists the rocks in order of increasing grain size and increasing grade of metamorphism?

    B. slate, phyllite, schist
  43. What is the major source of heat for contact metamorphism?

    B. heat from a nearby magma body
  44. In which setting would regional metamorphism be most likely?

    C. at great depths in the crust where two continents are colliding
  45. An Unconformity is a buried -

    D. surface of erosion separating younger strata above from older strata below
  46. The radioactive isotopes Uranium-238, Uranium-235, and Thorium-232 eventually decay to different, stable, daughter isotopes of -
    a. lead
    b. aragon
    c. iron
    d. strontium
    a. lead
  47. What fundamental concept states that in a horizontal sequence of conformable sedimentary strata, each higher bed is younger than the bed below it?

    B. law of superposition
  48. The ____ is the idea or concept that ancient life forms succeeded each other in a definite, evolutionary pattern and that the contained assemblage of fossils can determine geologic ages of strata?

    D. principle of faunal succession
  49. ____ refers to the process of fossilization where the internal cavities and pores of the original organism are filled with precipitated mineral matter.

    A. petrification
  50. What is the age of the earth accepted by most scientists today?

    D. 4.5 billion years
Card Set
Geol Test 2
Answers to the Second Exam