tems that sustain our fisheries (Plate 1). These processes, coupled with over fishing and the use of fishing techniques that are non-species-specific or physically damage habitats are raising questions about the sustainability of the nation's fisheries. Key to the protection and wise use of these resources is an understanding of the role of habitat in population dynamics, which are often dependent on the geologic framework and geologic and ocean processes in local areas.
The deep marine realm, beyond the continental shelf and out to the edge of the EEZ (Fig. 1-1), is commonly regarded as a distant region, unrelated to human endeavor; hence, it is often dismissed in terms of its impact on human life. However, many ostensibly coastal issues have an offshore component. The diversity of the nation's coastal and marine environments is in part due to offshore geologic processes. For example, off Oregon and Washington, volcanic and earthquake activity is concentrated near the edge of the EEZ along a mid-ocean ridge system, which is the longest volcanic mountain chain on our planet (Box 1-1). In this area, hydrothermal vents, similar to the more familiar hot springs of Yellowstone National Park, discharge hot fluids onto the seafloor; form mineral deposits rich in iron, copper, and zinc; and are the site of exotic biological communities. Enzymes from the bacteria found at these sites are now being used extensively in the biotechnology industry and are benefiting humankind through biomedical research. In contrast, the Gulf of Mexico has been dominated