Untitled Flashcards Set
GEOLOGIC TIME
Q: What is the difference between catastrophism and uniformitarianism?
A:
Catastrophism: Events that change Earth in a significant, sudden way.
Uniformitarianism: The principle that processes occurring now also occurred in the past and can explain Earth's history.
Q: What is relative dating?
A: The process of determining past events in relation to one another (arranging rocks in order).
Q: What is relative timing?
A: Determining the sequence of events (which happened first, second, etc.).
Q: What are the principles used in relative dating?
A:
Superposition
Lateral Continuity
Cross-Cutting Relationships
Baked Contacts
Xenoliths
Q: What is a baked contact?
A: When an igneous intrusion “cooks” the invaded country rock.
Q: What is a xenolith?
A: Fragments of rock incorporated into another rock during an intrusive event.
Q: What are unconformities?
A: Breaks in the rock record. Types include:
Disconformity
Angular Unconformity
Nonconformity
FOSSILS
Q: What are the different types of fossils?
A:
Original material
Molds
Replacement
Carbonized films
Footprints
Tracks
Q: What are pseudofossils?
A: Objects that look like fossils but are not.
Q: In which rocks do fossils occur?
A: Fossils are typically found in sedimentary rocks.
Q: What are index fossils?
A: Fossils that help determine the age of other rocks and the era they belong to.
ABSOLUTE DATING
Q: What is geochronology?
A: The study of the age of rocks and the history of Earth's formation through radioactive decay.
Q: What are some methods used for absolute dating?
A:
C14 (Carbon dating)
U-Pb (Uranium-Lead dating)
K-Ar (Potassium-Argon dating)
Q: What is magnetostratigraphy?
A: The comparison of magnetic signatures in strata to a global reference column to determine age.
Q: What is fission-track analysis?
A: Measuring the decay paths of isotopes to determine the age of rocks.
EVOLUTION
Q: What was Lamarck's theory of evolution?
A: Life forms change over time, and acquired traits can be inherited.
Q: What is Darwin’s theory of natural selection?
A: Organisms with advantageous traits are more likely to survive and reproduce, leading to the gradual evolution of species.
Q: What are the conditions for natural selection?
A:
More offspring than resources
Variation within species
Competition for resources
Selection of advantageous traits
Q: What is artificial selection?
A: The human-directed breeding of organisms with specific traits.
Q: What is homologous structure?
A: Organs of the same origin that evolve in different directions.
Q: What did Mendel contribute to evolution?
A: He conducted experiments on pea plants, discovering the inheritance of traits via genes.
PRECAMBRIAN
Q: How long did the Precambrian period last?
A: Over 80% of Earth's history (406 billion years to 540 million years ago).
Q: What occurred during the Hadean period?
A: The formation of Earth's crust, frequent volcanic activity, and the early lithosphere was mobile.
Q: What was the atmosphere like during the Archean period?
A: It was anoxic, with minimal oxygen and mainly composed of water vapor, carbon dioxide, and methane.
Q: How did oxygen first accumulate in Earth's atmosphere?
A: Through photosynthetic organisms, such as cyanobacteria, producing oxygen.
Q: What is banded iron formation (BIF)?
A: Layers of iron-rich minerals formed by the reaction of oxygen from photosynthetic organisms with dissolved iron.
PALEOZOIC
Q: What is the significance of the breakup of Rodinia?
A: The breakup of the supercontinent Rodinia around 750 million years ago influenced the formation of new oceans and continents.
Q: What was the major tectonic event during the Paleozoic?
A: The construction of the supercontinent Pangea.
Q: What caused the Appalachian Mountains?
A: The collision of tectonic plates during the closure of the Iapetus Ocean.
Q: What were the first vertebrates on land?
A: Amphibians, which evolved from fish during the Devonian period.
Q: What was the Permian extinction?
A: A mass extinction event that wiped out over 90% of species.
MESOZOIC
Q: What were the major tectonic events of the Mesozoic?
A:
The breakup of Pangea.
The opening of the Atlantic Ocean.
Q: What new forms of life appeared during the Mesozoic?
A:
Dinosaurs
Reptiles diversified
Flowering plants evolved.
Q: What was the first known bird?
A: Archaeopteryx, linking dinosaurs and birds.
Q: What caused the Cretaceous-Paleogene mass extinction?
A: An asteroid impact combined with volcanic eruptions.
CENOZOIC
Q: What tectonic events occurred during the Cenozoic?
A:
Reorganization of the West Coast of North America.
Formation of Central America.
Q: How did the Ice Age impact Earth during the Cenozoic?
A: Glaciations began, particularly in the Northern Hemisphere.
Q: What major life developments occurred during the Cenozoic?
A:
Mammals diversified.
Grasses evolved.
Flowering plants spread.
ANTHROPOCENE
Q: What is the Anthropocene?
A: A proposed epoch marked by significant human impact on Earth's geology and ecosystems, including climate change and deforestation.
Q: When is the Anthropocene thought to have started?
A: Some argue it began with the Industrial Revolution, while others trace it back to earlier events like the rise of agriculture.