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8Sci_Fossils/ Rocks
Fossils, Rocks & Geology (Mr. Tabat)
Question | Answer |
---|---|
What did scientists drill out to help them reconstruct Earth's history? | rock and ice cores |
What process involves the comparison of rock layers with others in a sequence to determine its age? | relative dating |
What is O-18:O-16? | the element isotope ratio Climate Scientists use as proxies to determine past climate changes on Earth |
What method is used to determine the most accurate and precise age of Earth's oldest rocks? | the uranium-lead method |
What are isotopes? | the same element with different atomic masses |
What is one of the major causes of missing rock layers in unconformities? | erosion |
What does a scientist need to know to figure out the absolute age of a rock? | the rate of decay for a radioactive element in the rock |
What could be used as evidence that a volcanic eruption occurred at a particular time in the past? | sulfates and ash in rock or ice cores |
What is an eon? | the largest division of geologic time |
What geologic time period ended with the largest mass extinction in Earth's history? | Permian |
What would provide the most evidence about the geologic history of the Earth? | studying sedimentary rock layers |
What phrase could be used to remember the principle of superposition? | younger over older |
What is an example of an unconformity? | a gap of about 1 billion years between two rock layers |
What is a trace fossil? | a fossil used to date surrounding rock layers |
What happens during radioactive decay? | radioactive isotopes break down into stable isotopes of other elements |
Where are most fossils preserved? | in sedimentary rock |
What would a large mudslide most likely form into? | a fossil formation |
What dating technique would you use to compare the ages of fossils found in layers of sedimentary rock? | relative dating |
What most likely causes ripple patterns on a layer of sedimentary rock? | the sediment was laid down at the bottom of a river with a fast current |
What is an index fossil? | a fossil that is widespread but found only in a short period of geologic time |
What is radioactive dating used for? | to determine the absolute age of a rock layer |
Why is the fossil record incomplete? | most organisms never became fossils |
What did Scientists study to learn about the Earth's history? | rocks and fossils |
What is Carbon-14 used for? | it is used in radioactive dating of once living material |
What method was used to help Scientists determine that Earth is about 4.5 billion years old? | radioactive dating |
What species was best suited to the climate change in early Earth history when the land became drier and warmer? | reptiles |
What is absolute dating? | finding the age of a rock based on the ratio of parent material to daughter material |
What are Trilobites? | early arthropods found throughout the oceans of the Earth that went extinct at the end of the Permian period |
Where are most fossils of animals and plants found? | sedimentary rocks |
What are Fusilinids? | a dominant form of Foraminifera during the late Permian |
What is an Ottonosia? | a type of algae that lived up until the Jurasic time period that was found in Kansas and parts of Northern Wyoming |