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Flashcards in 1q-28q Deck (26)
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0
Q

What is the definition of fossil?

A

Fossils are the remains of the traces of an organism that was once alive.

1
Q

How are fossils formed? (4 points)

A

An animal gets buried by sediment, layers accumulate above the remains, movement of tectonic plates lift sediment and push the fossil closer to the surface, and finally erosion helps to expose the preserved remains.

2
Q

What are two categories of fossils? (2 points)

A
  1. Fossilized body parts

2. Trace fossils

3
Q

The fossil record is generally incomplete. Why? (3 points)

A

The fossil record is generally incomplete due to;

  1. Poor preservation
  2. Poor observation & recovery
  3. Poor fossilization potential
4
Q

You have a better chance of becoming a fossil if you are…? (3 points)

A
  1. You have hard parts (teeth, bones, shells)
  2. You’re buried rapidly
  3. You’re prolific
5
Q

What are the five main types of fossils? (5 points)

A
  1. Petrified fossils
  2. Molds & casts
  3. Carbon films
  4. Trace fossils
  5. Preserve remains
6
Q

Explain what petrified means.

A

Turning into stone

7
Q

How are petrified fossils formed?

A

Minerals replace all or most of a part of an organism

8
Q

What is a most? A cast? (2 points)

A

Mold- indention of the shape of a dissolved organism on hardened rock
Cast- taking place Of the mold, when minerals fill the mold and replace the dissolving organism and harden as rock. Opposite of mold

9
Q

What is carbonization or carbon film?

A

Carbonization Is when a living thing dies and leaves a thin layer of carbon behind that shows the delicate parts of the object

10
Q

What 3 ways can remains get get preserved? (3 points)

A
  1. Amber- trapping an organism sticky resin then hardening
  2. Tar- tar covers an organism & soaks into bones to stop decaying
  3. Ice- an animals body is frozen & completely preserved
11
Q

What is entombing?

A

The process in which an organism is preserved in Amber

12
Q

What is mummification?

A

The process in which an animal or being dies in tar & the tar soaks into the bones to stop decay

13
Q

Explain how mold and cast fossils are made (2 points)

A

An animal does and gets buried under sediment & dissolves, leaving a mold or hole of its shape. Then, water and mineral soak into the mold and hardens into rock, creating a cast.

14
Q

What type of rock contains most fossils?

A

Sedimentary rock

15
Q

What are the three rock types?

A
  1. Sedimentary
  2. Metamorphic
  3. Igneous
16
Q

What is the law of superposition?

A

In undisturbed strata, the layer on bottom is oldest, those above are younger.

17
Q

Explain the entire rock cycle (3 points)

A

An igneous rock weathers and erodes and turns into sediment. Then, it is compacted and turns into sedimentary rock. Next, it is heated and put under pressure and turned I to metamorphic rock. Finally, the rock is heated, turned into magma, cooled, and turned back to its earliest stage which is igneous rock.

18
Q

How are rocks classified? (3 points)

A

Tecture, color, mineral composition

19
Q

Wat are two types of igneous rock? Explain how each are formed. (4 points)

A

Intrusive- when igneous are formed by MAGMA that cools BENEATH the earths surface
Extrusive-when igneous rocks are formed by LAVA ON earths surface

20
Q

What can cause rock layers to not be in order?

A

Violent conditions in the earth ( earthquakes, mountain building, faults, eruptions, etc.) disturb rock layers

21
Q

Explain the difference between the texture of rocks cooled in water, deep in earths surface, and at or near earths surface (3 points)

A

Cooled in water- cooled extremely fast, no crystals, vesicular- gas pockets
Cooled deep in earths surface- cools slowly, produces large crystals, coarse- grained texture
Cooke at or near earths surface- cools quickly, produces small crystals, fine- grained texture

22
Q

What is weathering?

A

A general term for all actions that break down or wear away rocks

23
Q

What is erosion?

A

The carrying away of sediment

24
Q

What is relative dating?

A

The determination of an object or organisms age in relation to another. An estimate

25
Q

What is absolute dating?

A

A method that uses radioactive analysis of the decay of isotopes in minerals to determine the actual time, in millions if years, when an organism died