Mid-ocean ridges occur along_________​ plate boundaries, where_________​ ocean floor is created as the Earth's tectonic plates spread_________​ As the plates separate, molten rock_________​ to the seafloor, producing enormous volcanic eruptions of basalt. The speed of spreading affects the_________​ of a ridge - slower spreading rates result in steep, irregular topography while faster spreading rates produce much_________​ profiles and more gentle slopes.​