Study Notes on Geology and Earth's History

Introduction

• Course Title: This Old Earth: A Trip Through Time

• Instructor: Rong-Yu Li, Ph.D, Department of Geology, Brandon University

• Earth’s Age: Approximately 4.6 billion years

Mass Extinctions

• Five major mass extinctions:

  • 5: End Cretaceous (~65 million years ago)

• Current concerns about a potential sixth mass extinction

• since 1500; 765 EXTINCT SPECIES

• since 1900: 477 extinct

• threatened w extinction: 48,600 species

• Tu Youyou = antimilaria

Global Issues

• Losing biodiversity (dodo bird and passenger pigeon)

• Overpopulation: Current world population is ~8.2 billion

• Global warming

• ex: tsunami in Canada - Burin Peninsula (1929) from earthquake

• ex: Quebec landslide = too much water w clay = unstable

Branches of Geology

• Physical Geology: Studies Earth's materials and surface processes

• Historical Geology: Chronological study of Earth’s events

Subsidiary Branches of Geology

• Paleontology

    Fossils as records of life's history

Layers: core (high density), mantle, crust (least density)

Theory: explanation for something supported by evidence

Hypothesis: proposed explanation for something that can be tested

Plate Tectonics

• plate tectonic theory: relationship between lithosphere, asthenosphere and plate boundaries

• Principle of Uniformitarianism: (James Hutton): the present is the key to the past

• Catastrophism: theory that sudden catastrophic events shaped the earth