What methods did scientists use for the seafloor?

Scientists used methods such as sonar mapping, deep-sea drilling, and submersibles to study the seafloor. Sonar mapping involves using sound waves to create detailed maps of the seafloor, while deep-sea drilling allows scientists to collect samples of rocks and sediments from the ocean floor. Submersibles are underwater vehicles that can be used to explore the seafloor up close and collect samples and data.