The three are different. The first is Molten Material,which is indeed erupting along mid-ocean ridges. The scientists dived to the ocean floor in Alvin, a small sumbarine. Alvin was built to withstand the crushing pressures four kilometers down in the ocean. A ridge's central valley, Alvin's crew found strange rocks shaped like pillows. Other rocks looked like toothpaste squeezed from a tube. Such rocks form only when molten material hardens quickly under again and again along the mid-ocean ridges.
The second is Magnetic Stripes, which are patterns of the ocean floor that provided more support for sea-floor spreading. Earth's magnetic poles have reversed themselves many times during Earth's history. The last reversal happened 780,000 years ago.
The third and final one is Drilling Samples, which came from rock samples obtained by drilling into the ocean floor. The Glomar Challenger, a drilling ship built in 1968, gathered the samples. The Glomar Challenger sent drilling pipes through water six kilometers deep to drill holes in the ocean floor. This feat has been compared to digging a hole into the sidewalk from the top of the Empire State Building.
Information from: California Earth Science Textbook, pages 152-153.
Hope this helps! ☺
-SmallvilleGrl
Granitic strips in the ocean floor ... Novanet
True. Bands of magnetic material in the sea floor that have opposite poles or exhibit magnetic reversal provide evidence for sea floor spreading. This is because as new oceanic crust forms at mid-ocean ridges, Earth's magnetic field periodically reverses, creating magnetic stripes on the ocean floor that align with the direction of the magnetic field at that time.
Ocean ridges and deep-sea trenches support the theory of sea floor spreading through the process of plate tectonics. At ocean ridges, new oceanic crust is formed as magma rises and solidifies, pushing the existing crust apart. Deep-sea trenches are areas where old oceanic crust is being subducted back into the mantle, completing the cycle of sea floor spreading. This continuous movement of crust at ridges and trenches provides evidence for the theory of sea floor spreading and the movement of tectonic plates.
Earthquake patterns, including their depth and distribution, can provide evidence of sea floor spreading by showing a concentration of earthquakes along mid-ocean ridges where new oceanic crust is being formed. As tectonic plates diverge and new crust is created, stress builds up and is released through earthquakes. The pattern of earthquakes along mid-ocean ridges provides a visual representation of the tectonic activity associated with sea floor spreading.
The discovery of mid-ocean ridges, where new oceanic crust is formed, supported the theory of sea-floor spreading. The mapping of magnetic stripes on the ocean floor, showing alternating patterns of magnetic polarity, provided further evidence for sea-floor spreading. The age of the oceanic crust getting progressively younger away from the mid-ocean ridges supported the concept of sea-floor spreading.
Not really but sea floor sediments thickness increase with increased distance from spreading centers which is good evidence. Other evidence such as magnetic reversals, temperature, dating methods provide the best evidence of seafloor spreading
Magnetic reversals
Magnetic minerals on the ocean floor.
Because of the stripes at the sea floor which are magnetic minerals
Magnetic reversals and sea floor spreading.
Magnetic reversals and sea floor spreading.
Magnetic reversals and sea floor spreading.
The spreading of the sea floor.
seafloor spreading, age of the sea floor and ocean trenches.
Because people love cats
It just did, you could see it
by the plate tectonic and the ocean bridges