Introduction to the Marine Environment from a Geological Perspective

Abstract

The oceans cover 71% of the Earth’s surface, and harbor 97.5% of its superficial water (much more is trapped within the planet’s interior). This represents the largest habitat for the development of life (roughly 97% of the biosphere, Prager and Earle 2000; Fig. 1.1) and in fact, all the major phyla of prokaryotes (archaea, bacteria, cyanobacteria) and eukaryotes (protists, fungi, plants and animals) have marine representatives. On a planetary scale, oceans make up only 0.13% of Earth’s volume (0.02% of its mass). The age of the ocean is about 4,000 million yr (MY), but the ocean and atmosphere have been in a steady state for around 800 MY.