Rocks, Fossils, and the GTS

Guiding Question: How do scientists use evidence to establish a timeline of Earth’s history?

Or, how do scientists use samples of rock strata to establish the Geologic Time Scale?


ESS1-4: Construct a scientific explanation based on evidence from rock strata for how the geologic time scale is used to organize Earth’s 4.6-billion-year-old history.

Students should be able to…

  1. Write a CLAIMlike how events in Earth’s history are organized relative to one another
  2. Identify & describe multiple pieces of EVIDENCE, including types and order of rock strata, fossil record, major events 
  3. Use REASONING to explain how rock strata, relative dating, the fossils record, and major events can be used to help construct Earth’s history

LS4-1: Analyze and interpret data for patterns in the fossil record that document the existence, diversity, extinction, and change of life forms throughout the history of life on Earth under the assumption that natural laws operate today as in the past.

Students should be able to…

  1. Organize data to find patterns (similarities & differences) in sample rock layers
  2. Identify relationships between rock layers, relative age, time period(s), and the presence/emergence/disappearance of organisms in the fossil record
  3. Analyze and interpret data to find patterns and evidence of mass extinctions, when organisms emerged, went extinct, or evolve, long-term increase in diversity and complexity of organisms

Class Activities:


Student understanding will be measured by:

  • Formative Assessment:
    • Rock Cycle Exit Slip
    • GTS CER via google classroom
  • Summative Assessment: GTS Quiz

Resources