Answer each question by selecting the correct blue button. Only the first answer selected is graded.1. Layers of volcanic ash often serve as useful geologic time markers because ash layers usually:
2. The time line below represents the geologic history of Earth. Letters A,B,C, and D represents specific times in Earth's history. Which letter best indicates when trilobites became extinct?
3. New York State has no bedrock from which geologic time period?
A. choice (A)
B. choice (B)
C. choice (C)
D. choice (D)
4. The diagram below shows a cross-sectional view of the Earth's crust. What does the unconformity (buried erosional surface) at the line XY represent?
A. an area of contact metamorphism
B. a time gap in the rock record of the area
C. proof that no deposition occurred between the Cambrian and Carboniferous periods
D. over turning of the Cambrian and Carboniferous rock layers.
5. Base your answer to the following question on the Earth Science Reference Tables and the map below. The arrows on the map show the location and orientation of glacial striations on the surface bedrock. Dark shading shoes the location of large moraines (glacial deposits). The Harbor Hill Moraine and the Ronkonkoma Moraine are believed to have formed during the:
A. Jurassic Period
B. Cambrian Period
C. Pleistocene Epoch
D. Pennsylvanian Epoch
6. Base your answer to the following question on the Earth Science Reference Tables, the graph below, and your knowledge of Earth science. The graph represents the decay of radioactive material X into a stable decay product. If radioactive material X were heated, the length of its half-life would:
C. remain the same
D. would be destroyed
7. The diagram below represents the skull of a saver-toothed tiger that died 30,000 years ago. The age of the skull could be determined most accurately by using:
8. The diagram below represents the present number of decayed and undecayed atoms in a sample that was originally 100 % radioactive material. If the half-life of the radioactive material is 1,000 years, what is the age of the sample represented by the diagram?
A. 1,000 years
B. 2,000 years
C. 3,000 years
D. 4,000 years
9. The diagram below shows the abundance of organisms called crinoids, blastoids, and echinoids throughout different geologic periods. The number of species living at any given time is represented by the width of the blackened areas. Which statement about crinoids, blastoids, and echinoids is best supported by the diagram?
10. Trilobite fossils from different time periods show small changes
in appearance. These observations suggest that the changes may be the result
A. They are now extinct
B. They came into existence during the same geologic period
C. They existed during the Devonian Period
D. They have steadily increased in number since they first appeared