The paleomagnetism of sea-floor rocks, and potassium-argon dating techniques prove that the sea’s floor is spreading out. The millions of years for this movement is added proof of the old age of the earth.
The ocean floors are 200 million years old. The earth’s crustal plates are moving apart from the mid ocean ridges.
The Facts Are .....
If the ocean's floors are 200 million years old, then at the present rate of sedimentation (25 billion tonnes per year), the sediments should be many kilometres deep, yet on average they are only 250 m thick. This indicates that the sea floors are not as old as the theory purports. The slow rate of subduction could only account for about 10% of this incoming sediment, so subduction cannot be used as a defence. More importantly, there are areas of the sea floor which are not part of any subduction zone (eg the Tasman Sea, off Australia), where the depth of sediment is similar to the average. 
The subduction of the ocean floor under the continents is seen as proof of the continental drift theory. Subduction however is not a rapid process that can be observed, rather it is inferred from geological and volcanic data. If subduction is occurring, then all the ocean trenches near the subduction should have compressed, deformed, and thrust-faulted sediments on their floors. However, the floor of the Peru-Chile and East Aleutian Trenches are covered with soft, flat-lying sediments which are devoid of these structures. 
Measuring the paleomagnetism of sea-floor rocks has not conclusively proved that plate movement is a fact. Deep crustal drilling in the North Atlantic Ocean has helped put this theory into disrepute. Science, Vol. 204, 1979 p:573-586; International Geology Review, Vol. 10, 1968 p:765-766; R. Doell & A. Cox "Magnetization of Rocks" in "; 
"..... paleomagnetic data are still so unreliable and contradictory that they cannot be used as evidence either for or against the hypothesis of the relative drift of continents or their parts." I.A. Rezanov in the article "Paleomagnetism and Continental Drift"
One of the linchpins of the plate tectonics theory is the 'proof' from potassium-argon (K-Ar) age assessments that the oldest rocks are furthest from the ridge crests. There are a number of scientists who have examined the K-Ar data, and believe that when correctly interpreted, they show no evidence of an increasing age with distance from the ridges. 
There are at least 4 theories to explain how the crust plates move. However, each of these mechanisms (either alone or together) cannot provide enough force to overcome the drag of the plates as they move over the magma. Also, they cannot explain how the plate boundaries originally formed. 
Satellite interferometry measurements taken by NASA, between 1979 and 1983, failed to show any plate movement. 
- Creation Ex Nihilo, Vol. 13, No. 3, 1991 p:29
- Geological Society of America Bulletin, Vol. 81, 1970 p:1339-1360;
- Geological Society of America Bulletin, Vol. 83, 1972 p:3613-3626
- Mining Geophysics", (Vol. 2), Society of Exploration Geophysics, 1967 p:452
- J.A. Jacobs "The Earth's Core and Geomagnetism", Pergamon Press: Oxford, 1967 p:106
- International Geology Review, Vol. 10, 1968 p:765-766
- Journal of Geology, Vol. 80, 1972 p:185-197; Science, Vol. 162, 1968 p:265-267;
- Science, Vol. 161, 1968 p:1132-1135
- Journal of Geology, Vol. 80, 1972 p:185-197
- Science News, Vol. 123. No. 2, 1983 p:20