Sea Floor Spreading. Mid-Ocean Ridges. Mid-ocean ridges are an undersea mountain chain where new ocean floor is produced. In the mid-1900’s, scientists begin mapping the mid-ocean ridges using SONAR. Mapping mid-ocean ridges, made scientists more curious. What are these ridges?
Evidence from molten material
In the 1960’s scientists sent Alvin, a submarine that could withstand the crushing pressures deep in the ocean.
Strange rocks were found. Rocks that looked like toothpaste squeezed from the tube. These types of rock only form when molten rock cools and hardens quickly after erupting.
Evidence from Magnetic Stripes
Evidence from Drill Samples