Geology Ch. 9 Test

43 Questions

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Geology Quizzes & Trivia

Geology Ch. 9 test dives deeper into the analysis of the different properties and minerals in regard to rocks and earth particles. How well have you understood the chapter? Take up the quiz and find out.


Questions and Answers
  • 1. 
    An unconformity is a buried ________. 
    • A. 

      Fault or fracture with older rocks above and younger rocks below

    • B. 

      Surface of erosion separating younger strata above from older strata below

    • C. 

      Surface of erosion with older strata above and younger strata below

    • D. 

      Fault or fracture with younger strata above and older strata below

  • 2. 
    The radioactive isotopes uranium-238, uranium-235, and thorium-232 eventually decay to different, stable, daughter isotopes of ________. 
    • A. 

      Iron

    • B. 

      Argon

    • C. 

      Strontium

    • D. 

      Lead

  • 3. 
    Which of the following best characterizes an angular unconformity? 
    • A. 

      Tilted strata lie below the unconformity; bedding in younger strata above is parallel to the unconformity.

    • B. 

      Horizontal lava flows lie below the unconformity and horizontal, sedimentary strata lie above.

    • C. 

      The discordant boundary between older strata and an intrusive body of granite.

    • D. 

      Tilted strata lie below the unconformity with loose, unconsolidated soil above.

  • 4. 
    Which of the following is not a very long-lived, radioactive isotope? 
    • A. 

      U-238

    • B. 

      K40

    • C. 

      Rb-87

    • D. 

      C-14

  • 5. 
    The ratio of parent to daughter isotopes in a radioactive decay process is 0.40. How many half-lives have elapsed since the material was 100% parent atoms? 
    • A. 

      less than l

    • B. 

      More than 3

    • C. 

      Between l and 2

    • D. 

      Between 2 and 3

  • 6. 
    Consider the names of the eras in the geologic time scale. What is meant by "zoic"? 
    • A. 

      Life; living things

    • B. 

      Rocks; lithified strata

    • C. 

      ) time; recording of events

    • D. 

      Places; geographic references

  • 7. 
    Which two Paleozoic, geologic, time-scale periods used in North America are combined into the Carboniferous period in Europe and elsewhere? 
    • A. 

      Triassic; Jurassic

    • B. 

      Cambrian; Ordovician

    • C. 

      Permian; Pennsylvanian

    • D. 

      Mississippian; Pennsylvanian

  • 8. 
    Which of the following geologic observations would not bear directly on working out the sequence of geologic events in an area? 
    • A. 

      Inclusions of sandstone in a granite pluton

    • B. 

      A well-exposed dike of basalt in sandstone

    • C. 

      The feldspar and quartz contents of a granite

    • D. 

      An unconformity between a granite and sandstone

  • 9. 
    What fundamental concept states that in a horizontal sequence of conformable sedimentary strata, each higher bed is younger than the bed below it? 
    • A. 

      Law of original correlation

    • B. 

      Theory of correlative deposition

    • C. 

      Law of superposition

    • D. 

      Theory of superstition

  • 10. 
    What of the following refers to the investigative process by which geologists identify and match sedimentary strata and other rocks of the same ages in different areas? 
    • A. 

      Super matching

    • B. 

      Correlation

    • C. 

      Strata indexing

    • D. 

      Cross-access dating

  • 11. 
    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? 
    • A. 

      Principle of cross correlation

    • B. 

      Law of fossil regression

    • C. 

      Law of correlative indexing

    • D. 

      Principle of faunal succession

  • 12. 
    Which of the following is an essential characteristic of an index fossil? 
    • A. 

      The organism lived only in specific environments such as beaches or estuaries

    • B. 

      The organism only lived for a short period of geologic time

    • C. 

      The fossils are exceptionally abundant and well preserved

    • D. 

      The fossils occur in deep-water marine sediments, but the organism actually lived in the sunlit, surface layer of the ocean

  • 13. 
    What gas is a radioactive daughter of the U-238 decay series that can accumulate to unhealthful levels in poorly ventilated uranium mines and home basements? 
    • A. 

      Xenon-143

    • B. 

      Carbon-14

    • C. 

      Radon-222

    • D. 

      Argon-40

  • 14. 
    ________ refers to the process of fossilization where the internal cavities and pores of the original organism are filled with precipitated mineral matter. 
    • A. 

      Replacement

    • B. 

      Petrification

    • C. 

      Carbonization

    • D. 

      Impression

  • 15. 
    Complex, invertebrate, life forms are common as fossils beginning with marine strata of Cambrian age. How long ago did the Cambrian period begin? 
    • A. 

      6 billion years

    • B. 

      54 million years

    • C. 

      540 million years

    • D. 

      65.4 million years

  • 16. 
    The rare element iridium has been implicated in which "ancient health" crisis? 
    • A. 

      Poisoning of primitive algae in the Hadean and Archean eons

    • B. 

      Extinction of the woolly mammoths in late Pleistocene time

    • C. 

      Disappearance of Neanderthal man during the early Cenozoic era

    • D. 

      Extinction of the dinosaurs at the end of the Cretaceous Period

  • 17. 
    What is the age of the Earth accepted by most scientists today? 
    • A. 

      6.4 billion years

    • B. 

      4.5 million years

    • C. 

      4.5 billion years

    • D. 

      6.4 million years

  • 18. 
    • A. 

      The atomic number of the daughter isotope is one more than the parent; the mass numbers are the same.

    • B. 

      The mass number of the daughter isotope is one more than the parent and both isotopes have the same atomic number.

    • C. 

      The daughter isotope has an atomic number two less than the parent and a mass number four less.

    • D. 

      The daughter isotope has an atomic number one less than the parent and a mass number two less.

  • 19. 
    The half-life of carbon-14 is about 6000 years. Assume that a sample of charcoal is formed by burning of living wood 15,000 years ago. How much of the original carbon-14 would remain today? 
    • A. 

      More than one-half

    • B. 

      Between one-fourth and one-eighth

    • C. 

      Between one-half and one-fourth

    • D. 

      Between one-half and one-third

  • 20. 
    Visualize five, horizontal, sedimentary strata exposed in a cliff or canyon wall identified by consecutive numbers, 1 being the lowest bed and 5 being the highest. Which of the following statements concerning the strata are true? 
    • A. 

      Bed 5 is the oldest

    • B. 

      Beds l and 3 are older than bed 4

    • C. 

      Bed 4 is older than bed 2

    • D. 

      Bed 3 is older than beds 2 and 4

  • 21. 
    Which of the following denotes the divisions of the geologic time scale in correct order of decreasing lengths of time beginning with the longest time interval and ending with the shortest? 
    • A. 

      Eon, era, epoch, period

    • B. 

      Era, period, epoch, eon

    • C. 

      Eon, epoch, period, era

    • D. 

      Eon, era, period, epoch

  • 22. 
    Assume that man's recorded history can be stretched back to 4600 years before the present. This is approximately what fraction of geologic time?  
    • A. 

      One ten-thousandth

    • B. 

      One millionth

    • C. 

      One billionth

    • D. 

      One hundred-thousandth

  • 23. 
    When a radioactive isotope decays by electron capture, the electron ________. 
    • A. 

      Combines with a neutron in the nucleus, raising the mass number of the daughter isotope by one

    • B. 

      Combines with a proton in the nucleus; the atomic number of the daughter is one less than the parent

    • C. 

      Makes the parent isotope into an ion with a charge of negative one

    • D. 

      Makes the daughter isotope into an ion with a charge of positive one

  • 24. 
    What is the source of natural carbon-14? 
    • A. 

      Cosmic ray collisions and neutron-capture involving atmospheric nitrogen

    • B. 

      Leakage of radioactive gases from the liquid, outer core

    • C. 

      Fusion of hydrogen and helium in the Sun and eruption of solar flares

    • D. 

      Nuclear fission of the heavy, radioactive elements uranium and thorium

  • 25. 
    ________ is an erosional contact between tilted, older strata below and horizontal, younger strata above. 
    • A. 

      An angular unconformity

    • B. 

      Inverse bedding

    • C. 

      A disconformity

    • D. 

      Cross cutting

  • 26. 
    Who made the first clear statement of the law of superposition? When? 
    • A. 

      Nicolaus Steno, 17th century

    • B. 

      John Stuart Priestly, 19th century

    • C. 

      William Smith, 18th century

    • D. 

      John Wesley Powell, 19th century

  • 27. 
    Sandstone strata and a mass of granite are observed to be in contact. Which of the following statements is correct geologically? 
    • A. 

      The sandstone is younger if the granite contains sandstone inclusions.

    • B. 

      The sandstone is younger if it shows evidence of contact metamorphism.

    • C. 

      The granite is older if the sandstone contains pebbles of the granite.

    • D. 

      The granite is older if it contains inclusions of sandstone.

  • 28. 
    The geologic time scale was devised before numerical dating using radioactivity was invented. 
    • A. 

      True

    • B. 

      False

  • 29. 
    Numerical age dates based on radioactivity are very important for studying Proterozoic geologic history because fossils are rare or absent. 
    • A. 

      True

    • B. 

      False

  • 30. 
    The term Mesozoic refers to life forms intermediate in complexity between early and much later, more modern-looking life forms. 
    • A. 

      True

    • B. 

      False

  • 31. 
    Most sedimentary rocks are readily dated by radiometric methods. 
    • A. 

      True

    • B. 

      False

  • 32. 
    After three half-lives, one-ninth of an original, radioactive, parent isotope remains and eight-ninths has decayed into the daughter isotope. 
    • A. 

      True

    • B. 

      False

  • 33. 
    A disconformity is an erosional unconformity with parallel beds or strata above and below. 
    • A. 

      True

    • B. 

      False

  • 34. 
    Phanerozoic, marine, sedimentary strata of the same age on different continents can usually be correlated by their fossil assemblages. 
    • A. 

      True

    • B. 

      False

  • 35. 
    The radioactive isotope, potassium-40, has argon-40 as a daughter product. 
    • A. 

      True

    • B. 

      False

  • 36. 
    The term Paleozoic describes the era of ancient life forms. 
    • A. 

      True

    • B. 

      False

  • 37. 
    Pebbles of granite in sandstone and conglomerate resting on the granite suggest that the granite intruded the sedimentary beds. 
    • A. 

      True

    • B. 

      False

  • 38. 
    Carbon-14 is produced by cosmic rays reacting with nuclei of iron atoms in the Earth's core. 
    • A. 

      True

    • B. 

      False

  • 39. 
    The Paleocene is the oldest epoch of the Tertiary period. 
    • A. 

      True

    • B. 

      False

  • 40. 
    Paleophrenology is the study of fossils and ancient life forms. 
    • A. 

      True

    • B. 

      False

  • 41. 
    Strata above an angular unconformity were tilted before the older strata were eroded. 
    • A. 

      True

    • B. 

      False

  • 42. 
    Correlation of rock units between continents or widely separated areas is accomplished by using physical features such as color, texture, and thickness of units.  
    • A. 

      True

    • B. 

      False

  • 43. 
    Rapid burial and possession of hard parts are necessary conditions for the preservation of plant or animal remains as fossils. 
    • A. 

      True

    • B. 

      False