Untitled Flashcards Set

What is the difference between catastrophism and uniformitarianism?

Catastrophism refers to significant, sudden events that change Earth, while uniformitarianism is the principle that processes occurring now also occurred in the past to explain Earth's history.

What is relative dating?

The process of determining past events in relation to one another (arranging rocks in order).

What is relative timing?

Determining the sequence of events (which happened first, second, etc.).

What are the principles used in relative dating?

Superposition, Lateral Continuity, Cross-Cutting Relationships, Baked Contacts, Xenoliths.

What is a baked contact?

When an igneous intrusion 'cooks' the invaded country rock.

What is a xenolith?

Fragments of rock incorporated into another rock during an intrusive event.

What are unconformities?

Breaks in the rock record, including Disconformity, Angular Unconformity, and Nonconformity.

What are the different types of fossils?

Original material, Molds, Replacement, Carbonized films, Footprints, Tracks.

What are pseudofossils?

Objects that look like fossils but are not.

In which rocks do fossils occur?

Fossils are typically found in sedimentary rocks.

What are index fossils?

Fossils that help determine the age of other rocks and the era they belong to.

What is geochronology?

The study of the age of rocks and the history of Earth's formation through radioactive decay.

What are some methods used for absolute dating?

C14 (Carbon dating), U-Pb (Uranium-Lead dating), K-Ar (Potassium-Argon dating).

What is magnetostratigraphy?

The comparison of magnetic signatures in strata to a global reference column to determine age.

What is fission-track analysis?

Measuring the decay paths of isotopes to determine the age of rocks.

What was Lamarck's theory of evolution?

Life forms change over time, and acquired traits can be inherited.

What is Darwin’s theory of natural selection?

Organisms with advantageous traits are more likely to survive and reproduce, leading to the gradual evolution of species.

What are the conditions for natural selection?

More offspring than resources, Variation within species, Competition for resources, Selection of advantageous traits.

What is artificial selection?

The human-directed breeding of organisms with specific traits.

What is homologous structure?

Organs of the same origin that evolve in different directions.

What did Mendel contribute to evolution?

He conducted experiments on pea plants, discovering the inheritance of traits via genes.

How long did the Precambrian period last?

Over 80% of Earth's history (406 billion years to 540 million years ago).

What occurred during the Hadean period?

The formation of Earth's crust, frequent volcanic activity, and the early lithosphere was mobile.

What was the atmosphere like during the Archean period?

Anoxic, with minimal oxygen and mainly composed of water vapor, carbon dioxide, and methane.

How did oxygen first accumulate in Earth's atmosphere?

Through photosynthetic organisms, such as cyanobacteria, producing oxygen.

What is banded iron formation (BIF)?

Layers of iron-rich minerals formed by the reaction of oxygen from photosynthetic organisms with dissolved iron.

What is the significance of the breakup of Rodinia?

Influenced the formation of new oceans and continents around 750 million years ago.

What was the major tectonic event during the Paleozoic?

The construction of the supercontinent Pangea.

What caused the Appalachian Mountains?

The collision of tectonic plates during the closure of the Iapetus Ocean.

What were the first vertebrates on land?

Amphibians, which evolved from fish during the Devonian period.

What was the Permian extinction?

A mass extinction event that wiped out over 90% of species.

What were the major tectonic events of the Mesozoic?

The breakup of Pangea and the opening of the Atlantic Ocean.

What new forms of life appeared during the Mesozoic?

Dinosaurs, diversified reptiles, and evolved flowering plants.

What was the first known bird?

Archaeopteryx, linking dinosaurs and birds.

What caused the Cretaceous-Paleogene mass extinction?

An asteroid impact combined with volcanic eruptions.

What tectonic events occurred during the Cenozoic?

Reorganization of the West Coast of North America and the formation of Central America.

How did the Ice Age impact Earth during the Cenozoic?

Glaciations began, particularly in the Northern Hemisphere.

What major life developments occurred during the Cenozoic?

Mammals diversified, grasses evolved, and flowering plants spread.

What is the Anthropocene?

A proposed epoch marked by significant human impact on Earth's geology and ecosystems.

When is the Anthropocene thought to have started?

Some argue it began with the Industrial Revolution or earlier events like the rise of agriculture.