Curated OER
What Happened First?
In this rock worksheet, students are given four diagrams of rock formation and they put them in order from the youngest event to the oldest event and explain each diagram.
Curated OER
What Happened First?
In this rock worksheet, students are given four diagrams of rock formation and they put them in order from the youngest event to the oldest. They explain each diagram.
US Geological Survey
U.s. Geological Survey: Geologic Time
A discussion of geologic time, how scientists use the concept, and how they have determined its span.