Time Scale

1. List all of the geologic periods in order from oldest to current. (Cambrian to Quaternary)
2. Since the extra credit question is so hard, come up with a mneumonic to help you remember it.



(Oldest to current)

• Precambrian

• Cambrian

• Ordovician

• Silurian

• Devonian

• Carboniferous

• Permian

• Triassic

• Jurassic

• Cretaceous

• Tertiary

• Quaternary
  

Pre Cam Ord Sil Dev Carbo Permian Tri Jur Cre Ter Qua

Trees

1. How can scientists tell the age of a tree by looking at the rings? Explain what that means.
2. How/why would this be useful?
3. Is this an example of relative or absolute dating?
4. Provide a picture or a tree ring sample.

A single growth ring is usually added each year, which can help you determine the age of the tree by counting the rings. Knowing the age of a tree can provide useful information like numerical dates for events in the historic and recent prehistoric past. This is an example of absolute dating.

[Un]conformity

Put letters A, B, C, D, and E in order from oldest to youngest. Explain the unconformities.

The Order From Oldest to youngest: D,A,E,B,C
An unconformity is a gap in the sedimentary rock record. The unconformity, in this picture above is between B and D,A,E, is a angular unconformity.

HELP!

Which do you think is potentially more dangerous: earthquakes or volcanoes? Why? Find an example of a specific earthquake or volcano and tell its story. Please include a picture.

I believe both are dangerous; you are able to lose homes and lives in earthquakes and volcanoes.

Earthquakes: A magnitude-7.9 quake in Sichuan province last year left almost 90,000 people dead or missing.

Volcanoes:

Damage Resulting from the Eruption of Mount St. Helens:
There were 57 people killed and many of their bodies have never been found, especially near the volcano where the debris was approximately 150 feet deep. Over 200 homes were destroyed along with 15 miles of railway and 185 miles of highway.

The Center of the Earth

1. How deep is the deepest mine in the world?

• One of the deepest mines in the world is the TauTona gold mine in South Africa, a mere 3.6 kilometers deep.

2. How deep would you have to dig to reach the mantle?

• You need to dig through 6,378 km of rock, mantle, and iron to reach the center.
  

3. Let's pretend that you and your friends tried to dig a hole in your backyard to find a shortcut to China. The thing is, you guys had special suits that could withstand extreme temperatures, so you would not die. If you were somehow able to reach the mantle, what would it look like? What kinds of things would you see? How about the outer core? Inner core? What would it look like as you approached the surface (the crust) on the other side?

• I believe the mantle would look like a large amount of dirt, and I would see lots of rock...and more rock...and magma. The crust on the other side would be hard yet thin.
  

My Grade?

I believe I deserve an A. Why? When I type my blogs posts, I try to do my best and have fun with it. I’d put a lot of effort in my work, re-examine all my blogs on a daily basis, and make sure I’ve done everything right. I want to learn. I want to understand. That’s why I think I deserve an A .

{I don't always feel lucky, but I'm smart enough to try.
--"Grand Canyon" by Ani Difranco }

Rock[s]

{Let's Rock! With Rocks!}

1. Identify the two main types of igneous rocks. Provide examples and descriptions of each.

The two main types are:

Intrusive: solidify below Earth's surface-

Gabbro is a coarse-grained, dark colored, intrusive igneous rock that contains feldspar, augite and sometimes olivine. The specimen shown above is about two inches (five centimeters) across.

Granite is a coarse-grained, light colored, intrusive igneous rock that contains mainly quartz and feldspar minerals. The specimen above is about two inches (five centimeters) across.

Extrusive: solidify on or above Earth's surface-

Andesite is a fine-grained, extrusive igneous rock composed mainly of plagioclase with other minerals such as hornblende, pyroxene and biotite. The specimen shown is about two inches (five centimeters) across.

Rhyolite is a light-colored, fine-grained, extrusive igneous rock that typically contains quartz and feldspar minerals. The specimen shown above is about two inches (five centimeters) across.

2. Identify the two main types of metamorphic rocks. Provide examples and descriptions of each.

The two main types are:

Foliated:produced by exposure to heat and directed pressure

Gneiss is foliated metamorphic rock that has a banded appearance and is made up of granular mineral grains. It typically contains abundant quartz or feldspar minerals. The specimen shown above is about two inches (five centimeters) across.

Slate is a foliated metamorphic rock that is formed through the metamorphism of shale. It is a low grade metamorphic rock that splits into thin pieces. The specimen shown above is about two inches (five centimeters) across.

Non-foliated: do not have a layered or banded appearance-

Marble is a non-foliated metamorphic rock that is produced from the metamorphism of limestone. It is composed primarily of calcium carbonate. The specimen shown above is about two inches (five centimeters) across.

Quartzite is a non-foliated metamorphic rock that is produced by the metamorphism of sandstone. It is composed primarily of quartz. The specimen above is about two inches (five centimeters) across.

3. Identify the two main types of sedimentary rocks. Provide examples and descriptions of each.

The two main types are:

Clastic: that are formed from mechanical weathering debris-

Breccia is a clastic sedimentary rock that is composed of large (over two millimeter diameter) angular fragments. The spaces between the large fragments can be filled with a matrix of smaller particles or a mineral cement which binds the rock together. The specimen shown above is about two inches (five centimeters) across.

Sandstone is a clastic sedimentary rock made up mainly of sand-size (1/16 to 2 millimeter diameter) weathering debris. Environments where large amounts of sand can accumulate include beaches, deserts, flood plains and deltas. The specimen shown above is about two inches (five centimeters) across.

Chemical: that form when dissolved materials precipitate from solution-

Rock Salt is a chemical sedimentary rock that forms from the evaporation of ocean or saline lake waters. It is also known by the mineral name "halite". It is rarely found at Earth's surface, except in areas of very arid climate. It is often mined for use in the chemical industry or for use as a winter highway treatment. Some halite is processed for use as a seasoning for food. The specimen shown above is about two inches (five centimeters) across.

Limestone is a rock that is composed primarily of calcium carbonate. It can form organically from the accumulation of shell, coral, algal and fecal debris. It can also form chemically from the precipitation of calcium carbonate from lake or ocean water. Limestone is used in many ways. Some of the most common are: production of cement, crushed stone and acid neutralization. The specimen shown above is about two inches (five centimeters) across.