Geology: Evidence of Continental Drift & Seafloor Spreading

Questions and Answers

What occurs at the mid-ocean ridge during seafloor spreading?

Sediment accumulates

Oceanic plates collide

Land masses are formed

Molten material rises from the mantle (correct)

The magnetic stripes created by seafloor spreading are uniform in width regardless of the stability of the Earth's magnetic field.

False

What phenomenon causes the newly formed rock at the mid-ocean ridge to align with the Earth's magnetic field?

Cooling and solidification of molten material

The patterns of alternating magnetic stripes on either side of the mid-ocean ridge are a result of changes in the Earth's __________.

magnetic field Signup and view all the answers

Match the following concepts with their descriptions:

Mid-ocean ridge = Site of molten material rising Magnetic stripes = Pattern indicating Earth's magnetic changes Mantle = Layer where molten material originates Cooling process = Aligns rocks with magnetic field Signup and view all the answers

Which of the following is evidence that supports the theory of continental drift?

Paleoclimate data Signup and view all the answers

Glacial striations are found only in cold polar regions.

False Signup and view all the answers

What evidence of continental drift is present in Antarctica?

Coal Signup and view all the answers

The study of _______ data helps scientists understand the past climate conditions of the Earth.

paleoclimate Signup and view all the answers

Match the following evidence types with their descriptions:

Paleoclimate data = Information from past climate conditions Glacial striations = Scratches on rocks indicating ice movement Coal = A fossil fuel found in non-polar regions Tropical areas = Regions that experience warm climates Signup and view all the answers

Study Notes

Evidences that Support Seafloor Spreading

Magnetic patterns at mid-ocean ridges show molten material rises and solidifies, aligning with Earth's magnetic field.
Alternating magnetic stripes form as the Earth's magnetic field changes, with stripe width indicating duration of stability.

Evidences that Support Continental Drift

Paleoclimate Data: Past climate signals suggest continents were once connected, featuring fossilized glacial striations in tropical regions and coal deposits in polar regions.
Continental positions from paleoclimate maps indicate:
- North America was adjacent to Europe and Asia.
- South America connected to Africa.
- Africa positioned near Asia.
- India located between Madagascar and Australia.
- Antarctica's tropical features reveal its past climate.
Geological features depicted include coal swamps, salt deposits, deserts, and coral reefs.

Rock and Mountain Correlation

Same age and type of rocks observed across different continents. For example:
- Appalachian Mountains in North America align with Caledonian Mountains in Europe.
- Karoo system in South Africa correlates with the Santa Catarina system in Brazil.

Fossil Evidence

Glossopteris: A woody tree up to 30 meters tall, emerged 299 million years ago, found across southern continents such as Australia, Antarctica, India, South Africa, and South America.
Cynognathus: A dominant reptile species that lived 250-240 million years ago, exclusively found in South Africa and South America.
Mesosaurus: A freshwater reptile resembling modern crocodiles, existed 286-258 million years ago, with fossils found only in South Africa and South America.

Apparent Fit of Continents

Continents' shapes suggest a puzzle-like fit, providing visual evidence for continental drift.
- South America and Africa align closely.
- India, Madagascar, and Africa share matching coastal outlines.

Description

This quiz explores the evidence supporting seafloor spreading and continental drift, including magnetic patterns, paleoclimate data, and geological features. Test your knowledge on how these phenomena are interconnected through geological history and rock correlations.