Definition of sea-floor spreading in English:

sea-floor spreading

noun

Geology
  • [mass noun] The formation of fresh areas of oceanic crust which occurs through the upwelling of magma at mid-ocean ridges and its subsequent outward movement on either side.

    • ‘The main figure demonstrates how sea-floor anomalies, also known as magnetic stripes, develop during sea-floor spreading.’
    • ‘After much thought, he proposed in 1960 that the movement of the continents was a result of sea-floor spreading.’
    • ‘Reversals of the Earth's magnetic field, allied to sea-floor spreading, have left their imprint in the form of a magnetic tape recorder on the sea-floor.’