Assignment 2 -continental drift activity-lines of evidence
Answer the following questions….
Explain how continental shapes and geologic features supported the idea of continental drift
Rocks were built side by side and as a result, land separated. There were rocks, sediments, and other specific structures observed in different regions and continents. They could have reached there only by the Process of Continental drift. Mountain ranges and rocks of the same age, structure, and sediment have been discovered. They have identical continents.
Give several specific examples of areas/features that support this idea.
Similar kinds of rocks with identical ages and periods are observed on either side of the Atlantic Ocean. Mountain ranges of identical structures, rock types, and ages are observed on both sides of the Atlantic Ocean.
Fossils (“Evidence from fossils: Distribution of organisms”)
Explain what fossils are
The preserved remains of animals and plants whose bodies were inserted in mud and sand under ancient rivers, seas, and lakes are known as fossils. It also preserved the trace of life older than 10,000 years. The remains of animals and plants have been preserved naturally.
Explain how the fossil record supported the idea of continental drift
Fossil records supported the theory of Continental Drift strongly. Scientists observed that fossils of similar animals and plants of similar ages are present in rocks. We got these rocks on the shores of different continents. This implies that they were added at the beginning.
Give several specific examples of fossil types and locations that support his idea.
Geologist Eduard Suess discovered in the first half of the 20th century that we could find the fossils of the seed fern Glossopteris in three different which implies that the continents are formed from one gigantic supercontinent at one time and drift apart later. Lystrosaurus provides important evidence that supports the theory of continental drift.
Glacier deposits (“More observations: glacial ages and other climate evidence) Explain what “glacial deposits” are- know what they are, do not just define them.
When a glacier moves, it leaves behind the settling of sediments. This is known as a glacial deposition. Glaciers pick up rock and sediments when they move over the land. Glaciers carried a mixture of unsorted sediment called glacial till.
Explain how evidence of past glacial activity supported the idea of continental drift
The transition of the plate tectonic began as a result of lubricating sediment, scraped from the slope of the first continent of the earth by glaciers. As a result of the movement of the glacier, we can observe scratches on the bedrock, which is embedded in the ice.
Give several specific examples of evidence of past glacial activity
Erratics (which includes Omar, jasper conglomerates, and tillites) support the evidence of glacial flow lines.
Other evidence for past glacial activity is recorded beneath the glacial drift on some bedrock surfaces. Scratches made when the rocks were frozen into basal ice made a scratch over the bedrock called striae.
Briefly, what does “continental drift” mean, and when was this idea proposed?
The horizontal movements of the constituent relative to the ocean basin and one another on a large scale during geologic time is known as continental drift. This idea was proposed by Alfred Wegener In 1912. The hypothesis contained no motive mechanism, and as a result, many scientists rejected this hypothesis. Arthur Holmes, the English geologist, proposed mantle convection for the mechanism of continental drift later.
Give one example of a pair of continents that were used to support the existence of Pangaea based on their shapes.
A pair of West Africa and South America
People who did not believe in continental drift jumped at the fact that the continents were not a perfect fit for each other. Based on your knowledge of oceanography, suggest why the continent shapes do not match perfectly with one another.
The continent shapes do not match perfectly with one another because the geological forces (which hold the continents together) eventually caused the continents to drift apart over time.
What is a fossil?
After the death of animals and plants, the remaining portion was inserted in sand and mud under ancient rivers, seas, and lakes and preserved. These are known as fossils. It also preserved the trace of a life whose age is more than 10,000 years. The remains of animals and plants have been preserved naturally.
Provide examples of fossils that Wegener used to support the existence of Pangaea AND where the fossils were located.
Wegener used examples of fossils to support Pangaea’s existence are Cynognathus, Mesosaurus, Glossopteris, and Lystrosaurus.
The fossils are located in India, Africa, and Antarctica.
How did people who did not believe in Pangaea explain the locations of these fossils?
Mountain ranges and rocks of the same age, structure, and sediment have been discovered. They have identical continents.
What is a glacier?
A glacier is a collection of ice produced from the snow (which was compacted) that drifts into the Ocean wholly and eventually.
Which environmental conditions are necessary for glaciers to form?
- Cold local climate or cold summer
- Heavy winter snow.
What is a glacial deposit?
When a glacier moves, it leaves behind the settling of sediments. This is known as a glacial deposition.
What does the presence of glacial deposits tell scientists about what the climate used to be like in a particular area?
Scientists can get information about the temperature of the past climate from O18, which is present in the glacial core. The amount of O18 would be less in polar ice if the global climate were cold, and the amount of O18 would be more in polar ice if the global climate were warm.
Explain how the presence of glacial deposits supports continental drift.
As a result of the movement of the glacier, we can observe scratches on the bedrock, which is embedded in the ice.
How did people who didn’t believe in continental drift explain the distribution of glacial deposits?
There were rocks, sediments, and other specific structures observed in different regions and continents. They could have reached there only by the Process of Continental drift.
