Volcanoes, Earthquakes, and Mountain Ranges

Introduction

• Topic: Understanding the relationship between volcanoes, earthquakes, mountain ranges, and plate tectonics.
• Objective: Describe and relate the distribution of active volcanoes, earthquake epicenters, and major mountain belts to plate tectonic theory.

Earth's Structure

• Earth's Layers: Crust, Mantle, Outer Core, Inner Core.
  • Continental Crust: Forms continents, thick (30-50 km), older.
  • Oceanic Crust: Under oceans, thinner (5-10 km), denser, younger.

Lithosphere and Tectonic Plates

• Lithosphere: Outermost layer includes the crust and upper mantle.
• Tectonic Plates: Lithosphere is broken into large and small pieces that move slowly.
  • Movement is driven by heat and currents in the mantle.
  • Plates can move apart, collide, or slide past each other.

Geological Features and Events

• Mountains: Formed by colliding plates.
• Volcanoes: Often formed by subduction (one plate diving under another).
• Earthquakes: Occur when plates slide past or collide.

Distribution of Geological Features

• Active volcanoes, earthquake epicenters, and mountain ranges tend to be located near each other.
• These are all tied to plate boundaries and movements.

The Pacific Ring of Fire

• Region: Known for being geologically active with frequent earthquakes and volcanic eruptions.
• Philippines: Located in this region, experiencing high tectonic activity.

Tectonic Plates Affecting the Philippines

1. Philippine Sea Plate: Causes earthquakes and volcanic activity.
2. Eurasian Plate: Northwest interaction with the Philippine Sea Plate.
3. Pacific Plate: Influences earthquakes and volcanic activity east of the Philippines.
4. Sunda Plate: Affects the southern Philippines.

Conclusion

• Plate Tectonic Theory: Explains the distribution and interaction of Earth's crust through moving plates.
• Geologic activity, such as earthquakes, volcanism, and mountain formation, shapes Earth’s surface.
• Next lesson: Discussion on plate boundaries.

Study Tip: Review maps showing the distribution of tectonic activity to understand the correlation between geographic features and plate tectonics.