This volume belongs to a series on Oceanography. It is designed so that it can be read on its own, or used as a supplement in oceanogrphy courses. After a brief introduction to sea-floor sediments, the book shows how the activities of marine organisms cycle nutrients and other dissolved constituents within the oceans, and influence the rates at which both solid and dissolved material is removed to sediments. It goes on to review the carbonate system and shows how sediments that come from continental areas may be transported to the deep sea, explores what sea-floor sediments have taught us about the history of the oceans, and describes the biological and chemical processes that continue long after sediments have been deposited on the deep sea-floor. It covers the basics on the occurrence, distribution, and cycling of chemical elements in the ocean. It features full-color photographs and beautiful illustrations throughout. It includes reader-friendly layout, writing, and graphics. Pedagogy includes chapter summaries, chapter questions with answers and comments at the end of the book; highlighted key terms; and boxed topics and explanations. It can be used alone, as a supplement, or in combination with other Open University titles in oceanography.