This unique addition to reference literature provides an introduction to the major concepts and contemporary issues that are essential for students of environmental science and environmental studies to know. With over 200 entries authored by world-class names like Anthony Brazel, John Day and Edward Keller, this text is divided into six sections: Environmental Science, Environments, Paradigms & Concepts, Processes & Dynamics, Scales & Techniques, and Environmental Issues.
Volcanic rocks are the attention grabbers of the geologic world, coming into being in the most dramatic ways: as basaltic lava flows oozing across sugar cane fields in Hawaii or flowing down hillslopes into the sea, or as explosive eruptions that produce tuffaceous pyroclastic rocks that blanket entire areas in the way Mount Vesuvius destroyed Pompeii in AD 79. The most abundant volcanic rock is basalt that forms the floors of the oceans, which cover 79% of the Earth's surface (Table 43). Basalt is derived by partial melting of upper mantle rocks and erupts relatively passively from the mid-ocean ridges like blood oozing from a cut.
Table 43 Common volcanic rocks
The island arcs of the Earth, such as those around the northern and ...