Fossils
Rocks
Things that didn't fit into other categories
Smarty Pants
Pictures!
100
Define: Fossil
Preserved remains of traces of living things
100
Define: Sedimentary rock
A rock that is made up of hard sediments. This is the type of rock fossils are usually found in.
100
Define: Decomposition AND list 3 types of decomposers
When fungi or bacteria break down (aka decomposer) organism into smaller pieces.
Types: Fungi, Bacteria, insects, worms, slugs
100
Describe two ways that a WHOLE organism (soft and hard body parts) can become fossilized.
tar, amber, ice
100
Which pie chart to the right best represents the
amount of time that humans have been on earth
relative to all of Earth’s history?
4
200
Define: paleontologist
scientist who studies fossils
200
Give 3 examples of sediment
Sand, calcium (chalk), dirt, pebbles, shells, clay, silt
200
Define: Deposition
When eroded sediments settle down and stop moving (are deposited)
200
In what type of rock
1)would you most likely find fossils?
2) would you not most likely find fossils?
sedimentary - because the sediments harden around the organism
igneous - would melt fossil (magma) metamorphic - always changing due to heat and pressure
200
What happened most recently?
Intrusion of A
300
What is it called when you compare the age of a rock or fossil to another rock or fossil.
Relative Age/Dating
300
Define: Igneous Intrusion
Hot magma cutting through existing rock, then cooling into igneous rock.
300
Name a type of calendar geologists and paleontologists use to put the events of earth's past in proper order.
Geological Time Scale:
300
Give two reasons why many organisms don’t become fossils.
Reason 1: Not protected (not buried quick enough)
Reason 2: Decomposers can break the organism down before it has a chance to fossils.
300
A has been broken down and eroded, therefore that means it is weak compared to the other layers.
400
What is the difference between preserved fossil and mold fossil
A preserved fossil is prevented from decaying by being trapped in rock, ice, tar or amber. In a mold fossil, the organism decays leaving a cavity in the shape of the organism.
400
Define: Stratum
layers of sedimentary rock stacked on top of each other
400
What forms when organisms or parts of organisms are pressed between layers?
Carbon Film
400
Which statement can best be supported by the fossil record?
(1) Humans have lived on Earth throughout most of geologic history.
(2) The organisms on Earth have not changed.
(3) Most life-forms that existed on Earth have become extinct.
(4) Life started on land before in the water
3!
400
Between which two layers is there a gap in the fossil record because that rock that has eroded away?
A and B
B and C
C and D
There is no gap
2!
500
Name 6 types of fossils AND explain them
Body Fossil: fossils that are entire bodies of hard parts of the organism that has fossilized (an actual age is not determined)
Trace Fossil: form when the mud or sand hardens to stone where a footprint, trail, or borrow was left behind.
Preserved Fossil: forms when the entire organism or parts of organisms are prevented from decaying by being trapped in rock, ice, tar or amber.
Mold Fossil: forms when sediments bury an organism and the sediments change into rock; the organism decays leaving a cavity in the shape of the organism.
Cast Fossil: forms when a mold is filled with sand or mud that hardens into the shape of the organism
Petrified Fossil: “turn into stone” - forms when minerals soak into the buried remains, replacing the remains and changing them into rock.
500
Explain the difference between mechanical and chemical weathering
Chemical Weathering: Rock is broken down into smaller pieces that are made of different materials than the original rock. The rock type changes.
Examples: acid dissolving and oxidation
Mechanical Weathering: Rock is broken down into smaller pieces that are made of the same materials than the original rock. No change in rock type.
Examples: Frost wedging, wind & water abrasion, plant and animal
500
What is it called when weathered materials are carried somewhere else?
Erosion
500
What is rule #1 of relative dating?
The bottom rock layer of sedimentary rock usually... is the oldest
500
Which statement about the geologic history of the area is best supported by the evidence in the diagram?
The rocks at A formed before those at B.
The rocks at D folded after the deposition of rock layer B.
A long period of erosion took place before the formation of rock layer B.
Layers C, D, E, F, G formed in a folded pattern and were never horizontal to start
3!