SOLVED

21) 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 22) 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 23) 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 24) 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 25) ________ is an erosional contact between tilted, older strata below and horizontal, younger strata above. A) Inverse bedding B) An angular unconformity C) A disconformity D) Cross cutting 26) Who made the first clear statement of the law of superposition? When? A) John Wesley Powell, nineteenth century B) William Smith, eighteenth century C) John Stuart Priestly, nineteenth century D) Nicolaus Steno, seventeenth 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) Assume that you have just examined several flat-lying sedimentary layers. After much study you determine that there is a considerable span of time for which no sedimentary rock layer exists at this site. You have just discovered a(n) ________. A) angular unconformity B) series of conformable strata C) disconformity D) example of cross-cutting relationships 29) A worm would stand a poor chance of being fossilized because ________. A) worms have been rare during the geologic past B) worms have no hard parts C) worms contain no carbon-14 D) all of these 30) The era known as the “age of mammals” is the ________. A) Precambrian B) Paleozoic C) Mesozoic D) Cenozoic