1. under which of the following conditions would a fossil most likely form?
a. a living thing dies and sediment is very slowly deposited on top of its body.
b. a living thing dies and sediment quickly covers its body.
c. a living thing dies and its skeleton is left exposed to the elements.
d. a living thing dies and a radioactive element breaks down its body.
2. if you were looking for an example of a trace fossil, for which of the following might you search?
a. footprints and trails b. a whole body preserved in rock c. dinosaur teeth d. a hardened mineral sample 3. what does the law of superposition tell about the relative ages of rocks?
a. that the deeper you go into rock layers, the older the rocks are
b. that the deeper you go into rock layers, the younger the rocks are
c. that the oldest rock layer is always on top d. that the oldest rock layer is always undisturbed
4. after a rock layer is eroded, which additional event must occur to create an unconformity, or a gap in the geologic record?
a. an earthquake or motion along a fault b. new deposits of sediment must build up on the eroded area
c. folding of sedimentary rock layers d. a volcanic eruption 5. radioactive decay occurs when atoms a. lose mass. b. join with atoms of another element. c. break down to form atoms of another element. d. are exposed to chemical weathering. 6. if you wanted to consult the geologic time scale for when the first vertebrates evolved, where would you look?
a. in the section for the ordovician period of the paleozoic era
b. in the section for the quaternary period of the cenozoic era
c. in the section for the triassic period of the mesozoic era
d. in the section for precambrian time 7. earth’s atmosphere, oceans, and continents began to form during the first several hundred million years of
a. precambrian time. b. the paleozoic era. c. the mesozoic era. d. the cenozoic era. my answers: a. a living thing dies and sediment is very slowly deposited on top of its body.
a. footprints and trails a. that the deeper you go into rock layers, the older the rocks are
c. folding of sedimentary rock layers. c. break down to form atoms of another element. d. in the section for precambrian time a. precambrian time.