Table of Contents
How did magnetic field in the Earth contribute to the continental drift theory?
Scientists used magnetometers to show where the north magnetic pole had been when magnetite crystals cooled. The magnetic pole seemed to have moved, but had not. The simplest explanation is that the continents have moved. Apparent polar wander is another line of evidence for drifting continents.
What supports the theory of continental drift?
The evidence for continental drift included the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones.
How does magnetic reversal support the theory of continental drift?
One of the key pieces of evidence supporting plate tectonic theory was the discovery that rocks on the seafloor record ancient reversals of the Earth’s magnetic field: as rocks are formed where plates are moving away from one another, they record the current direction of the Earth’s magnetic field, which flip-flops …
Why is Earth’s magnetic field useful?
Generated by the motion of molten iron in Earth’s core, the magnetic field protects our planet from cosmic radiation and from the charged particles emitted by our Sun. It also provides the basis for navigation with a compass.
How does the fit of the continents support continental drift?
In the early part of the 20th century, scientists began to put together evidence that the continents could move around on Earth’s surface. The evidence for continental drift included the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones.
What does the theory of continental drift state?
Continental drift was a revolutionary theory explaining that continents shift position on Earth’s surface. He proposed that Earth must have once been a single supercontinent before breaking up to form several different continents.
What does the magnetic field protect Earth from?
cosmic radiation
Generated by the motion of molten iron in Earth’s core, the magnetic field protects our planet from cosmic radiation and from the charged particles emitted by our Sun.
How do Earth’s magnetic pole reversals provide evidence for plate tectonics apex?
Rocks have no magnetic material, so they are unaffected by reversals. How do Earth’s magnetic pole reversals provide evidence for plate tectonics? Rocks become more magnetized as you move away from ocean ridges.
What happens when the earth’s magnetic field reverses?
Every so often, at irregular intervals, the Earth’s magnetic field reverses; the magnetic north pole becomes a south pole, and vice versa. When the continents drift, there is a rift opening between the diverging continents. There is one all the way down the (approximate) centre of the Atlantic.
How did Wegener contribute to the continental drift theory?
Wegener found other corresponding matches, e.g. between rock formations along matching edges, and in 1918 he proposed his theory of ” continental drift “–that continents, like ice floes, drifted from one location to another.
What caused the continents to drift?
He believed the continents floated on deeper layers below them, which over millions of years gave way like a thick fluid and made the drift possible. The energy source was supposedly the internal heat of the Earth.
Why is the earth’s magnetic polarity different on each strip?
Every half million years, on the average, the Earth’s magnetic polarity reverses, and so does the magnetization of the ocean floor. Each strip therefore represents an epoch of one or the other magnetic polarity, and the symmetry is also explained.