7.10.A:  describe the evidence that supports that Earth has changed over time, including fossil evidence, plate tectonics, and superposition; and

Describe

EVIDENCE THAT SUPPORTS THAT EARTH HAS CHANGED OVER TIME

Including, but not limited to:

• Plate tectonics

  • Continental drift theory – the hypothesis that Earth’s continents were once one large landmass and have moved over geologic time relative to each other

    • Proposed in 1912 by Alfred Wegener

    • A large supercontinent breaking apart (Pangaea) 

    • Continents in motion

    • No explanation regarding a mechanism to explain movement

    • Evidence might include: 

      • Continents fit together like puzzle pieces.

      • Fossil and rock correlation

      • Superposition (law of) – Each rock layer is older than the one above it.

      • Fossils on the edge of one continent were like those on the facing edge of the matching continent’s corresponding rock layer.

      • Index fossils – widely distributed organisms that lived during only one short period of time 

  • Plate tectonics – scientific theory that explains how major landforms are created 

    • Proposed in 1960 by Harry Hess

    • Development of mechanisms (convection currents in the mantle) for continental drift

    • Magnetic striping and reversal

    • Correlation of fossil data from drilling on either side of the mid-ocean ridge

    • Seismic activity zones and plate boundaries – Ring of Fire

    • Location of mountain ranges

Describe

EVIDENCE THAT SUPPORTS THAT EARTH HAS CHANGED OVER TIME

Including, but not limited to:

• Fossil evidence

  • Fossils – mineral replacements, preserved remains, or traces of organisms that lived in the past

  • Index fossils – widely distributed organisms that lived during only one short period of time

  • Fossils on the edge of one continent were like those on the facing edge of the matching continent.

Describe

EVIDENCE THAT SUPPORTS THAT EARTH HAS CHANGED OVER TIME

Including, but not limited to:

• Superposition