In the process of sea floor spreading, where does molten material rise form the mantle and erupt?

Question

This is a question on my Science Final Exam and I can not find the answer in my book. So if you could help me that'd be great :)

Answer 1

Right down the center of the Atlantic.

Answer 2

In the mid Atlantic (mid-ocean) ridge causing undersea eruption and ridge-building.  This continues on North through Iceland, causing eruptions there.

Perhaps the best known of the divergent boundaries is the Mid-Atlantic Ridge. This submerged mountain range, which extends from the Arctic Ocean to beyond the southern tip of Africa, is but one segment of the global mid-ocean ridge system that encircles the Earth. The rate of spreading along the Mid-Atlantic Ridge averages about 2.5 centimeters per year (cm/yr), or 25 km in a million years. This rate may seem slow by human standards, but because this process has been going on for millions of years, it has resulted in plate movement of thousands of kilometers. Seafloor spreading over the past 100 to 200 million years has caused the Atlantic Ocean to grow from a tiny inlet of water between the continents of Europe, Africa, and the Americas into the vast ocean that exists today.

The volcanic country of Iceland, which straddles the Mid-Atlantic Ridge, offers scientists a natural laboratory for studying on land the processes also occurring along the submerged parts of a spreading ridge. Iceland is splitting along the spreading center between the North American and Eurasian Plates, as North America moves westward relative to Eurasia.

In rifts, no crust or lithosphere is produced. If rifting continues, eventually a mid-ocean ridge may form, marking a divergent boundary between two ...

Answer 3

Plate boundries, I think.

The crust of the earth moves around on top of the mantle in the form of enormous plates. The boundries of the plates are where magma from the crust/mantle boundry rises to the surface, creating more plate material. Old material gets pushed beneith ajacent plates along subduction zones.

The mid Atlantic ridge is a good example of sea floor spreading. It sits approximately in the middle of the Atlantic ocean. It is largely unnoticed because it is on the bottom of the ocean, but in the northern Atlantic it forms volcanic islands. Iceland is one such island and is so geologically active it uses geothermal energy to produce much of it's energy. The mid Atlantic ridge was also used to prove the theory of continental drift. The idea of crustal plates moving was not accepted at first until magnetic measurements were taken of lava deposits along the ridge. It was seen that there were bands of oppositely magnetised lava. Fresh lava is magnetised by the earth's magnetic pole, which has changed direction in the past. The bands showed the continents had drifted apart over time and as the magnetic poles fluctuated, they left a record of continental drift in the magnetic orientation of the lava bands in the mid Atlantic ridge. It is possible the magnetic field will change again within the next thousand years.

Answer 4

a divergent plate boundary

as the two plates move apart, magma flows into the space between the two plates and creates new land