how old the the sea floors, I watched a documentry that said that the sea floors are less 80M years old?

Answer 1

The oldest oceanic crust is 180 million years old. It is located near Siberia in the northwest part of the Pacific Basin. The youngest oceanic crust is less than one second old. It is constantly being renewed. I can't figure where that documentary came up with an age of 80 million years old. Perhaps it was an average of all the oceanic crust.

Answer 2

Sea floors are not a single age - the age of the sea floor across the mid-Atlantic ridge is just about zero (magma bubbling up right now) while the sea floor off the coast of California is probably much older than 80M - it is in the process of subducting under the North American continent - of course there are new sediments on old floors as well - if you measured the age of the Marianas trench, the upper few feet might be very 'new' yet it may have been under the ocean for a long time.

Answer 3

obviously the documentry was citing the facts gathered from observations and testable evedence supporting the theory of an 80 million year old sea floor

1. techtonic sea floor spreading is slow, 1 inch a year

2, minerals in the sea floor have there iron particals aranged to follow the magnetic field of the earth. the iron alway points north and ever 250,000-750,000 years the geo-magnetic field reverses. or swaps sides. north goes to the bottom and south to the top. the earth DOES NOT flip over just the polarity of the magnetic field. the magnetic flip is rutine so can be mesure how often it has happend thus helps to measure the oldest part of the sea floor