Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
8Sci_EarthHistory1
Mayfield - Earth History 2016
| Question | Answer |
|---|---|
| What are the 3 eras further divided into? This is also the third largest division of geologic time. | periods |
| Define, absolute dating. | the process of establishing the age of an object by determining the number of years it has existed |
| What can be used to test past climates? | ice cores |
| Define, index fossils. | fossils or organisms that lived during a relatively short, well-defined geologic time span |
| Define, uniformitarianism. | it states that the Earth has been changing gradually over time |
| Define, geologic column. | the master key of all rocks and fossils on Earth. |
| Define, carbon dioxide. | a gas scientists extract from ice cores to study |
| Define, trace fossil. | any naturally preserved evidence of animal activity |
| Define, Paleobotanists. | scientists who study plant fossils |
| Define, isotope. | elements with the same number of protons but different number of neutrons |
| What does the principle of superposition state? | that younger rocks lie above older rocks |
| What radiometric dating method would be used to date mammoth remains? | carbon-14 |
| Would a turtle, spider, wasp or bird most likely be fossilized? | a turtle |
| What can ice cores be used to determine? | past climates |
| What best represents the Paleozoic Era? | marine life, Old life, & Cambrian Explosion |
| Where can most fossils be found? | sedimentary rock |
| Most paleontologists agree there have been at least how many mass extinctions? | 5 |
| What two ways can an unconformity be created in? | erosion and nondeposition |
| What are 3 different types of unconformities? (know how to draw each one) | disconformity, nonconformity, & angular unconformity |
| What are 4 different types of rock layer disturbances? Explain each one. | 1. fault - break in the earth's crust 2. intrusion - igneous rock that has crept into an existing rock layer 3. folding - wavy rock due to pressure 4. tilting - slanted rock due to pressure |
| What is glaciation and how does it affect sea level? | formation of glaciers (when water freezes into to large blocks of ice) lowers sea level |
| Rock layers were found containing 30 kg of radioactive elements that had a half life of 5 million years. How old were the rock layers if scientists determined that the samples had originally contained 120 kg of the radioactive materials? | 120 (1) - 60 (2) - 30 2 x 5 = 10 million years old |
| The half-life of a radioactive element, such as carbon-14, is the time it takes for half of the atoms of the element to decay. How many half-life periods have passed if a fossil contains 1/32 of the original amounts of carbon-14? | 1/1 (1 half-life), 1/2 (2 half-lives), 1/4 (3 half-lives), 1/8 (4 half-lives), 1/16 (5 half-lives), 1/32 = 5 half-lives |
| Potassium-42 has a half-life of 12.4 hours. How much of an 848 g sample of potassium-42 will be left after 62.0 hours? | 62 divided by 12.4 = 5 half lives 848 (1 half life) - 424 (2 half lives) - 212 (3 half lives) - 106 (4 half lives), 53 (5 half lives) - 26.5 grams 26.5 grams are left after 62.0 hours |
| Explain absolute dating. (include parent/daughter material and half-life) | telling exact age of an object in years. half-life it takes for 1/2 parent to decay / stabilize into daughter - constant rate (explain this in essay form) |
| There are 5 ways/locations organisms can be preserved or fossilized. Name all 5 with an explanation of each. (in essay form) | 1. petrification - usually wood - mineral replacement 2. Ice - best preserved 3. amber - smaller organisms - hardened tree sap 4. rock - sedimentary 5. asphalt/tar |
| What are index fossils? Name and describe 2 examples with descendants. (In essay form) | lived during short, well-defined time period Examples: Ammonite (230-208 mya) related to modern day nautilus Trilobite (400 mya) related to modern day horseshoe crab |
| Explain the 1 of the 3 different eras. (In essay form) | 1. Paleozoic - old life, marine life, Cambrian explosion, 1st era with good fossil record. ended with largest extinction event (90%) due to sea water circulation changes |
| Explain the 1 of the 3 different eras. (In essay form) | 2. Mesozoic - age of dinosaurs/reptiles - ended with 15-20% extinction event |
| Explain the 1 of the 3 different eras. (In essay form) | 3. Cenozoic - age of mammals - still happening - mammals flourished due to 1) warm blooded & 2) carry young inside mother until birth |
Created by:
masonteach
Popular Earth Science sets