Author Question: Describe how Fred Vine and D. H. Matthews related the seafloor-spreading hypothesis to magnetic ... (Read 136 times)

itsmyluck · **on:** Jul 14, 2018

Describe how Fred Vine and D. H. Matthews related the seafloor-spreading hypothesis to magnetic reversals.

What will be an ideal response?

Question 2

Describe slab pull and ridge push. Which of these forces appears to contribute more to plate motion?

What will be an ideal response?

shoemake · **Reply #1 on:** Jul 14, 2018

Answer to Question 1

After researchers discovered alternating stripes of high- and low-intensity magnetism, Vine and Matthews suggested that the stripes of high-intensity magnetism are regions where the paleomagnetism of the ocean crust exhibits normal polarity, while low-intensity magnetism is due to reversed polarity. They reasoned that as magma solidifies along narrow rifts at an oceanic ridge, it is magnetized with the polarity of the existing magnetic field, and because of seafloor spreading, these strips are carried away in opposite directions.

Answer to Question 2

Slab pull is subduction of cold, dense slabs of oceanic lithosphere acting as the driving force of plate motion. Ridge push is a gravity-driven mechanism resulting from the elevated position of the oceanic ridge, causing slabs of lithosphere to slide down the flanks of the ridge.