Hydrothermal vents form in mid-ocean ridges where tectonic plates are spreading apart and seawater percolates down fissures and is heated by hot magma. They were first seen in 1977 in the Galapagos Islands by scientists who discovered that bacteria were converting toxic vent materials into usable energy for other organisms that had never been seen before.Know More
In areas where the Earth´s plates are spreading apart, seawater circulates under the ocean´s crust and is heated. When the heated water rises again to the ocean floor´s surface, it is vented as plumes.
The hottest, darkest plumes are black, rich in sulfur and can reach heights of up to 18 stories tall. White plumes are cooler and smaller in size and contain barium, calcium and silicon.Learn more about Earth Science
Seafloor spreading is an oceanic process involving the formation of new oceanic crust through the solidification of basaltic magma at mid-ocean ridges. This process is a partial explanation for the process of Continental Drift.Full Answer >
Continental drift is caused by movement of the tectonic plates that continents sit on top of. Continental drift has continuously occurred throughout time, and continues to do so today. Rough estimates say that Europe and North America are drifting away from each other 2.5 centimeters per year.Full Answer >
Mid-ocean ridges form when tectonic plates meet beneath the ocean and ridge-push, slab-pull or do both to create a subduction zone. Over time, one plate raises up. This, along with the simultaneous magma buildup, creates a submarine mountain range, or ocean ridge.Full Answer >
Encyclopædia Britannica states that many pieces of evidence support the sea floor spreading theory of plate tectonics, including increased heat flow along mid-ocean ridges, geomagnetic anomalies near ocean ridges, thickness of marine sediments and age of sediments. Sea floor spreading was first proposed by geophysicist Harry Hess in 1960 after reviewing submarine data. The theory is the basis for modern plate tectonics that states plates in the Earth's crust move.Full Answer >