Theory Of The Earths Floor Spreading Question And Answers

Geologist harry hess finally proved that wegener was right.

Theory of the earths floor spreading question and answers. Subduction theory supposes that converging plates are destroyed below ocean trenches. This is a 50 000. If sea floor spreading occurs without plate destruction the quantity of crust will increase and the volume of the earth must increase. Seafloor spreading is a process that occurs at mid ocean ridges where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge answer choices.

2 in the 1960 s scientists finally found what was missing in wegener s theory. The earth s crust is one solid plate that is glued in place on top of the layers below. Sea floor spreading answer key. Corollary to the idea of plate accretion by sea floor spreading is the notion of plate destruction by subduction.

What is the mechanism for sea floor spreading that heralded the advent of full blown plate tectonic theory. Hess believed that sea floor spreading is the answer to the mystery of continental drift. The lithosphere is made up of. Centrifugal force from the spinning earth mantle convection cells the pull of the sun and the moon and associated gravitational forces the earth s magnetic field ocean currents dragging along the seafloor.

The theory of seafloor spreading explains that earth s continents move because they ride atop ocean crust as it moves way from ocean ridges. The continents are moving apart. Seafloor spreading is happening at b. Is the idea that the continents are slowly drifting further away from each other.

This is a mid ocean ridge. For instance the atlantic ocean is believed to be expanding because of its few trenches. 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. A theory that states the earth s crust is broken into plates that float on the asthenosphere.

Molten rock pushes up from the asthenosphere and pushes the plates apart at the mid ocean ridge. Subduction and sea floor spreading are processes that could alter the size and form of the ocean. It is an underwater mountain range that forms when magma pushes up on the crust at a divergent boundary. The ocean floor has remained essentially unchanged since the formation of the earth.

A combination of the seafloor spreading theory and the continental drift theory. Using paleomagnetism these rocks were known to have preserved an imprint of the changes in the earths magnetism over long periods of geological time which proved the theory of sea floor spreading.