Which of the following phenomena is not used to support the hypothesis of seafloor spreading? * 1.magnetometers were able to show that the patterns of magnetic reversal of each side of an ocean ridge are symmetrical 2.the thickness of sediment increases as the distance from an ocean ridge increases 3.the development of isochron maps revealed that the age of the crust increases as distance from on ocean ridge increases 4.the development of sonar revealed that the ocean floor is flat