Y9 6.5 Tectonic Plates

Which of the following best describes what makes convection currents in the Earth's mantle?

• The mantle is cooled by the core through radiation, causing it to contract and sink, creating convection currents.

• The mantle undergoes phase changes due to pressure variations, leading to the formation of convection currents.

• The mantle undergoes phase changes due to pressure variations, leading to the formation of convection currents.

• The mantle is heated by the core through conduction. This expands, becomes less dense and rises through the mantle; cooling occurs next to the crust and then molten rock sinks again

• The mantle experiences chemical reactions with the crust, generating heat and causing convection currents to form.

What is meant by the term "tectonic plate"?

• A tectonic plate is a layer of magma located between the Earth's core and mantle.

• A tectonic plate is part of the Earth's crust that can move; it is supported on the mantle and moves on the mantle.

• Tectonic plates are giant cracks that form in the Earth's crust due to volcanic activity.

• A tectonic plate is a type of meteorological phenomenon that occurs in the Earth's atmosphere.

• Tectonic plates are large formations of ice found near the Earth's poles.

The continents of Earth appear to fit together like a jigsaw puzzle. Explain how this provides evidence for tectonic plates.

• The continents fit together due to the Earth's gravitational forces aligning them in specific patterns.

• The continents' arrangement is a consequence of volcanic activity shaping the land, not tectonic plates shifting.

• The continents' fitting together is a result of erosion and weathering over millions of years.

• The continents' shapes are formed by the magnetic fields of the Earth, causing them to align in specific configurations.

• Continents were once connected. They split due to moving plates. Coastlines show separation. They could fit again.

Describe how fossil records provide evidence for the movement of tectonic plates.

• Some fossils of the same species are found in continents where they appear they were once fitted together.

• Fossil distribution across continents is merely coincidental and unrelated to large-scale geological processes.

• The presence of similar fossils in different continents is attributed to ancient land bridges or migration patterns.

• Fossils found in various continents result from global geological activity, such as volcanic eruptions or seismic events.

• Fossils in different continents are the result of localized environmental factors, such as climate change or sea level fluctuations.

How does the alignment of magnetic materials in rocks help support plate tectonics?

• Magnetic materials in molten rocks line up with the North of Earth's magnetic field. The seafloor spreading pattern shows that it has switched when the poles have switched.

• Magnetic materials in molten rocks line up with the South of Earth's magnetic field. The seafloor spreading pattern shows that it has switched when the poles have switched.

• Magnetic materials in molten rocks line up with the North of Earth's magnetic field. The seafloor staying still shows that it has stayed aligned with the poles.

Magnetic rocks, fossils, continent shapes all provide ______________ for plate tectonics.

What of the following does not provide evidence for plate tectonics?

• where Earthquake and volcanoes have the most activity

• fossils being found on the same continent

• continents have shapes that seem to fit together like a jigsaw puzzle

• the pattern of seafloor spreading matching the the polarity of the Earth

• conduction currents explaining why plates are moving

Scientists think that Earth's magnetic field has reversed 183 times in 83 million years. What is the average time of between reversal events?

• every year

• every 45 years

• every 450 years

• every 450000 years

Why does the Hawaiian hot spot not support plate tectonics?

• the volcanoes do not form near the plate boundaries

• the plates near the hot spot do not fit together like a jigsaw puzzle

• there are no earthquakes there

• i dunnah.

How do earthquakes provide evidence for the movement of tectonic plates?

• Earthquakes are caused by the shifting of tectonic plates along fault lines, demonstrating their movement.

• Earthquakes are random events and do not relate to the movement of tectonic plates.

• Earthquakes occur due to volcanic activity and have no connection to tectonic plate movement.