GEOLOGIC TIME.8

Name:____________________________
Due Date:_________________________

EAS-100-51: EARTH SCIENCE
HOMEWORK No. 8

ACROSS CLUES 

DOWN CLUES

  • 4. Time required for half  of a given amount of parent radioisotope to decay into a daughter isotope.
  • 7. The era of ancient life.
  • 8. Common expression for past periods of prolonged continental glaciation.
  • 9. Concept that explained Earth's geology as the work of short-term (often supernatural) events.
  • 11. A creationist's estimate of the earth's age would be a relatively - - - number of years.
  • 13. Evidence of a period of erosion, as seen in outcrops, of as a wavy line in a geologic events column.
  • 16. Concept assuming that earth processes at work today had always operated during the earth's past, as well.
  • 19. Due to a hostile environment on land during the geologic past, life probably originated at - - -.
  • 20. The remains or traces of ancient life, generally dated at 10,000 or more years old.
  • 21. Geochronologists specialize in determining this property in geologic materials.
  • 22. A fossil particularly good for correlating outcrops between different areas.
  • 24. The Pennsylvanian Period was known as the Age of - - - -.
  • 27. To establish the equivalence of rocks of similar ages between different localities.
  • 29. The determination of the absolute age of a rock or fossil is known as - - - - - -.
  • 30. A word used to describe a past or present species of life that no longer exists.
  • 31. The Tertiary Period saw the development of a large species of saber-toothed - - -.
  • 32. Ectothermic animals have a body temperature that reflects their environment; meaning they are - - - - blooded.
  • 33. Old dinosaur movies used to end with a big earthquake and the explosion of a - - - - - -.
  • 34. The geological period during which hard skeletal parts first evolved, allowing preservation of fossils.
  • 1. The Tertiary and Quaternary Periods are subdivided into a shorter time unit called the - - - - -.
  • 2. Due to metamorphism, fossils that would be found in a shale would not be found in a - - - - -.
  • 3. From ancient Greek, the word for "terrible" as in "terrible lizards" (Mesozoic land reptiles).
  • 4. Due to gravity, all sedimentary rocks were originally oriented in the - - - - - - - - - - position.
  • 5. A rare example of complete fossil preservation is the woolly mammoth found trapped inside - - -.
  • 6. If you found the - - - of a dinosaur, it would be one of the most rare and valuable fossils.
  • 10. Parallel layers of sedimentary rock.
  • 12. Endothermic animals maintain a constant body temperature, and are known as - - - - blooded.
  • 14. The principle of ------------  relationships says "the cutter is older than the cuttee." (2 words)
  • 15. The study of ancient life.
  • 17. A type of absolute age determination that compares parent and daughter isotopes.
  • 18. The law of ------------- says that the rocks on the bottom are older than the rocks on the top.
  • 23. The largest unit of time on the geologic time scale.
  • 25. Major extinctions of life have been caused by climatic changes due to global - - - - - movements.
  • 26. The use of radiometric dating would produce a relatively - - - - number for the age of the earth.
  • 28. A column of rocks in the field, exposed by erosion, representing a sequence of geologic events.
  • 29. Scientific information, usually gathered by observation or experimentation. 

 

Copyright © 1989 by William K. Tong