Plate tectonics From Hypothesis to Theory a Plate tectonics is a scientific theory that explains two centuries of often puzzling observations and hypotheses about our planet earth a The continents are drifting very slowly across the face of our planet a Continental drift is a concept with a long history.Plate Tectonics: From Hypothesis to Theory ◼ Plate tectonics is a scientific theory that explains two centuries of often puzzling observations and hypotheses about our planet Earth. ◼ The continents are drifting very slowly across the face of our planet. ◼ Continental drift is a concept with a long history