Sponsored Links
This presentation is the property of its rightful owner.
1 / 12

Geology PowerPoint PPT Presentation

  • Uploaded on
  • Presentation posted in: General

Geology. The study of Earth. We d ivide g eology into two categories:. Physical Geology: To understand Earth’s long history. To understand the changes it has undergone.

Download Presentation





Presentation Transcript


The study of Earth

We divide geology into two categories:


Historical Geology: To establish a timeline of the vast number of physical and biological changes that have occurred in the past and may occur in the future

The Formation of Our Galaxy

  • It is believed that our solar system formed 4.56 billion years ago.

That is 4,560,000,000 years ago.

It all started with the remnants of a defunct or dead star.

Formation (continued)

  • The star exploded and there was a tremendous amount of dust and small particles floating around. Called a solar nebula

  • The particles and dust began to spin.

    The heavier particles stayed closer to the center than the gaseous particles.

Particles Collide

  • As the particles rotated around a center area, they banged into each other.

  • These central particles formed billions of small “planetesimals”. These were about 1 km in diameter.

  • Gravity began to pull the heavier particles toward the middle

The Sun Ignited!!!!

What Happened Then?

  • When the sun ignited, it began a process called fusion. This is where hydrogen gets pushed together and form a new material helium. It also releases a tremendous amount of energy.

  • The energy pushed the gas particles far away, while the heavier planetesimals were not as affected.

Over Millions of Years

  • The solid planetesimals collided to make bigger bodies (Earth and Venus)

  • The gaseous area collided together to form some of the larger outer planets.

What about Earth?

  • Earth was a mix of radioactive elements, iron, nickel and assorted others. It was getting bombarded by other smaller particles and was expanding quickly.

- The heat from the collisions and the radioactive decay caused some melting in the interior of the Earth

The Layersof Earth

  • This heat allowed some of the materials to melt and the denser ones would move to the center.

  • The less dense materials would “float” to the top.

  • This sinking and floating is still occurring today.

  • The center of our Earth is very hot with much molten iron and nickel.

Atmosphere and Oceans

  • Trapped gaseous materials are allowed to escape the core today and they still do through volcanic eruptions.

  • These eruptions that have occurred, much more frequently earlier, have pushed out enough gaseous materials to form our atmosphere.

  • Because we have an atmosphere that condenses, we have water, and oceans.


Complete questions 1-7 on page 5

Also complete the key concepts and vocabulary for the first 3 sections of Chapter 1.

  • Login