Interpreting Earth's History

Planet Earth formed about 4.6 billion years ago from an accumulation of rock, dust and gases drawn together by its own gravity. To unravel the mystery of our evolving planet from dust to the development of life, to the present, Geologist, like detectives, hunt for clues and evidence.
There are several fundamental principles that guide geologists in interpreting and reconstructing the sequence of geologic events that have occurred throughout Earth history.
The fundamental principles are:
  • Uniformitarianism
  • Superposition
  • Original Horizontality
  • Crosscutting Relationships (intrusions, folds, and faults)
  • Fossils

This week we will focus on the importance of fossils in the rock record and in establishing a geologic sequence. We will also look at how rocks are correlated or how we match similar rock strata in different locations to see if they formed at the same time or under similar conditions.

HOMEWORK: due Wednesday April 9th.

In review book (Thomas McGuire, 2nd edition), read pages 115-124; do questions 1-14 on pages 119-121.
Provide full written responses to all questions.

Test on Friday, April 11, 2008. Test topic is: interpreting earth history.

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