Abstract Intraplate volcanism within the Pacific Plate not generated at spreading plate margins is most obvious in Hawaii and the Hawaiian-Emperor volcanic chain. This chain forms a global relief feature of the first order. This chapter consists of five separate sections that summarize the volcanism and geology of Hawaii and the Hawaiian-Emperor chain. Less obvious but probably greater in overall volume are other seamounts and seamount chains scattered across the northern and eastern Pacific basin. Some of these appear to owe their origin to intraplate volcanism, but many probably formed at mid-ocean ridges. Batiza (this volume, Chapter 13) discusses these other, largely submarine, volcanoes. The Island of Hawaii lies at the southeastern end of the Hawaiian-Emperor volcanic chain—a dogleg ridge, largely submarine, stretching nearly 6,000 km across the north Pacific Ocean basin. From Hawaii the chain extends northwestward along the Hawaiian Ridge to a major bend beyond Kure Atoll. North of the bend the chain continues in a northward direction as the submarine ridge of the Emperor Seamounts. Volcanoes are active at the southeast end of the chain and become progressively older to the northwest, reaching ages of 75 to 80 million years at the north end of the Emperor Seamounts. Most of this volcanic chain, with an estimated area of 1,200,000 km 2 , lies beneath the ocean. Only the Hawaiian Islands and a few atolls of the Hawaiian Ridge, totaling some 16,878 km 2 , rise above the sea (Plate 5).

Abstract This volume will synthesize and describe the geology of the eastern northern Pacific Ocean Basin, a particularly large, variable, and dynamic region that is far less studied than most continental areas. Interpretation of the geology and geophysics of oceanic regions has been remarkably useful for elucidating the geometry and history of large-scale tectonics, especially lithospheric plate tectonics. Because it is accomplished by remote sensing techniques that generalize sea-floor structures and features, the structural complexities that are observed onshore at road-cut scales are smoothed out in marine studies. Thus, in many ways the success of marine studies is that they observe the forest without the confusion of looking at each tree, while on land the geologist must try to interpret the forest by the more difficult task of generalizing the study of features with the relative size of the trees. In the past few years the scales of onshore and offshore geologic studies have been converging. Continental geologists are using more geophysics and remote sensing, while marine geologists have tried to conduct higher-resolution studies. This volume will strive to provide a comprehensive description of our present state-of-knowledge of marine geology. At the same time, we will emphasize two general objectives in our field, as follows: