Evidence That The Ocean Floor Is Spreading

His theory of sea floor spreading maintained that new basaltic oceanic crust forms at a midoceanic ridge and is slowly pushed away on both sides toward the continents as more new crust is produced.

Evidence that the ocean floor is 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 of the ocean floor in the 1950s what they discovered was that the magnetism of the ocean floor around. The magnetism of mid ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. Due to this continuous seafloor spreading occurs and makes atlantic ocean floor to be connected to other continental crust making the ocean gets wider over the time. For instance the atlantic ocean is believed to be expanding because of its few trenches.

Eruptions of molten material magnetic stripes in the rock of the ocean floor and the ages of the rocks themselves. This evidence led scientists to look again at wegener s hypothesis of continental drift. In the 1960s geologist harry hess proposed that the sea floor was moving outward from the midoceanic ridges. Variations in the intensity and polarity of earth s magnetic field are considered to be recorded in the remanent magnetism of the igneous rocks as they solidified and cooled through the curie temperature at the crest of an oceanic ridge and subsequently.

Measurements indicate that new crust moves away from a ridge at. See also continental drift a veritable legion of evidence supports the seafloor spreading hypothesis. Several types of evidence supported hess s theory of sea floor spreading. Subduction and sea floor spreading are processes that could alter the size and form of the ocean.