Week of January 19th

Week of January 19th
We continued a lab that we didn't finish last week. We had 6 different trays of rocks and we had to decide if they were metamorphic, igneous, or sedimentary rocks based on each types of rocks characteristics. We said that sedimentary rocks, which are formed by mud, clay, or sediment that undergoes pressure can be all different colors, they have layers, they sometimes have holes, sandy, and are softer(when you pick at the rock sediment will come off). Igneous rocks which are formed by cooled magma or lava sometimes have holes, are varying sizes, have crystals, sometimes looks like glass, and is also in all colors. Metamorphic rock which is formed from rock that undergoes pressure and heat is all colors, has crystals, and has layers.

What types of things do geologists need to do in order to come up with reasonable conclusions about rock formations?

• they have to be able to see all sides of the rocks, so they can cut samples of the rock cut of the mountain
• they would need to know where the rock came from
• they would need to the the climate of from where the rock came from
• they would have to identify different layers in the rock
• they could clean the rock and then after its dry make observations

Week of January 12th

Week of January 12th
This week we learned about how different rocks form from lava when cooling. When the lava has a lot of time to cool large crystals form in the rock. When the lava doesn't have a lot of time to cool crystals still form, but they are just smaller.

We did a lab that showed the cooling rates. We melted moth balls and poured them into test tubes. Then they were poured into a hot, cold, and room temputure bowls. After they all are cooled we compared them. The one that cooled in the ice bowl looked like it had a lot of air bubbles and that it didn't have a lot of time to seperate. The one that cooled with heat was clear around the edges, but in the center it is foggy and you can't see through it.

Week of 1/5

Week of January 5th

This week we learned how to determine how old a rock is. To find that out you can use the Law of Superstition, which is that the older rock layers are at the bottom because younger rock layers are deposited over the older rock layers.

We Also learned about convection currents. When the particles are moving faster they become less dense and the lava underneath the lithospere rises up. When the particles move slower they become more dense and the lava sinks back to the bottom. This process repeats itself over and over again.