Evidence Ocean Floor Spreading

The minerals contained in the rocks are oriented opposite to the magnetic field.

Evidence ocean floor spreading.

What evidence was used to support sea floor spreading 1. Evidence of sea floor spreading 1. Magnetic rock alignment 5. Harry hess s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory.

Eruptions of molten material magnetic stripes in the rock of the ocean floor and the ages of the rocks themselves. In the 20th century the magnetic survey was conducted in the mid ocean ridge in order to investigate evidence of sea floor spreading. See also continental drift a veritable legion of evidence supports the seafloor spreading hypothesis. An exceptionally high rate of spreading approximately 4 5 cm year in the south pacific enables one to.

Rock dating techniques rock samples were taken at different locations near the mid ocean ridge. The rates obtained are in exact agreement with those needed to account for continental drift. Evidence of sea floor spreading. Basalt the once molten rock that makes up most new oceanic crust is a fairly magnetic substance and scientists began using magnetometers to measure the magnetism.

This evidence was from the investigations of the molten material seafloor drilling radiometric age dating and fossil ages and the magnetic stripes. Hydrothermal vents are common at spreading centers. By using the magnetometer the magnetic polarity will be shown through a timescale that contains the normal and a reverse polarity. Older rocks will be found farther away from the spreading zone while younger rocks will be found nearer to the spreading zone.

Abundant evidence supports the major contentions of the seafloor spreading theory. At a spreading center basaltic magma rises up the fractures and cools on the ocean floor to form new seabed. Several types of evidence supported hess s theory of sea floor spreading. Rock dating techniques 2.

This evidence led scientists to look again at wegener s hypothesis of continental drift. First samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid ocean ridge is approached and the sediment cover is thinner near the ridge.