Prentice-hall, inc • building vocabulary fill in the blank to complete each statement. 6. a device that scientists use to map the ocean floor is - 7. the feature on the ocean floor at c is called a(n) - 8. the process that continually adds new material to the ocean floor is called 9. the process by which the ocean floor sinks into the mantle is called 10. the chain of mountains that extends into all of earth's oceans is the teaching resources f. 29 inside earth