Gsc Ocean

Chapter 1

Why is the ocean salty if rain is fresh?

Cardon dioxic is absorbed by rain, slightly acidic rain dissolves the rocks and evaporates and leaves behind the tiny bit of salt behind.

How did life develop on the early earth?

Stanley Miller proposed, he put a mixture of gases and used lightning to break down the molecules and since the molecules will rearrange, and he found amino acids. Once you photosynthesize the by product is oxygen.

The Earth is at least 4.5 billion years old, found a rock of Zircon crystals in the Canadian Shield. Ancient core piece of continent is called craton.

Radiometric dating, use the half life of the carbon decay rating to figure out the isotope.

Hadean period when we start our geologic time. Archean – first life. First non-plant organism was insects.

Chapter 2 – Plate Tectonics and the Ocean Floor

Ships went from Europe around the world, they started mapping. Alfred Wegenr put forth a theory that made sense, his theory – at some point in time it was a single large continent called Pangaea, ocean called Panthalassa, the continents have moved since then. He as 4 pieces of information, first the continents fit, second he found places that could not support glaciers but with glaciers, third he found matching rock sequences separated by ocean, and fourth within the rocks he found the same fossil. Flaws – gravitational attraction of the Sun and Moon drove the drift, not possible, second the continents rammed through the crust like ice breakers, third continents rammed into each other build mountains however not all mountains are built this way.

During WWII, used sonar to map the sea floor, discovers mid-Atlantic Ridge. Paleomagnetism – the study of Ancient magnetic field. Iron particles in magma align themselves with the Earth’s magnetic field. Started drilling the sea and discovered that the earth’s magnetic field flips hundreds of time.

Samples either side of the Mid-Atlantic ridge had identical age, identical chemical...