In the past, interest in sedimentary structures has arisen mainly from the expectation that these features might be a guide to the environment of depo sition. But many sedimentary structures have also proved useful in determining stratigraphic order in nonfossiliferous, steeply inclined beds especially in Pre cambrian terranes. As the sequence problem has been reviewed at length by Shrock, it seemed to us, therefore, that the time is now ripe for a new look at sedimentary structures, not with respect to "top and bottom," but with reference to "fore and aft. " Much of the present-day interest in these structures stems from their usefulness in mapping of paleocurrents. A stage has been reached where there is need for a work which assembles, digests, and organizes our collective knowledge of the usefulness of directional properties of sediments and their application to basin analysis. This we have attempted to write. The desirability and need for such a book occurred to both of us independently. Upon discovering our mutual interest, we decided that a better book could be written by collaboration. Fortunately this collaboration became a reality because of support by the Guggenheim Foundation of one of us and the cooperation and support of The Johns Hopkins University of both of us. We acknowledge with thanks this indispensable aid.

This book is written for the student new to the subject as well as for the experienced geologist whose work leads him to the study of sedimentary basins.

Review of the second edition "For geologists and geophysicists studying sedimentary fill of basins, this volume is a valuable addition to their shelves. The book is packed with informationincludes numerous lists of references, and is up-to-date. As a source volume, this book is second to none. It is clear and well organized." GEOPHYSICS

This book is intended as a practical handbook for those engaged in the task of analyzing the paleogeographic evolution of ancient sedimentary basins. The science of stratigraphy and sedimentology is central to such endeavors, but although several excellent textbooks on sedimentology have appeared in recent years little has been written about modern stratigraphic methods. Sedimentology textbooks tend to take a theoretical approach, building from physical and chemical theory and studies of mod ern environments. It is commonly difficult to apply this information to practical problems in ancient rocks, and very little guidance is given on methods of observation, mapping and interpretation. In this book theory is downplayed and the emphasis is on what a geologist can actually see in outcrops, well records, and cores, and what can be ob tained using geophysical techniques. A new approach is taken to stratigraphy, which attempts to explain the genesis of lithostratigraphic units and to de-emphasize the importance of formal description and nam ing. There are also sections explaining principles of facies analysis, basin mapping methods, depositional systems, and the study of basin thermal history, so important to the genesis of fuels and minerals. Lastly, an at tempt is made to tie everything together by considering basins in the con text of plate tectonics and eustatic sea level changes.

In the extensive field of earth sciences, with its many subdisciplines, the trans fer of knowledge is primarily established via personal communication, during meetings, by reading journal articles, or by consulting books. Because more information is available than can be assimilated, it is necessary for the individual to search selectively. Books take more time from the inception of an idea until publication than any of the other means of communication men tioned. As a consequence, their function is somewhat different. Many good books are a compilation of up to date knowledge and serve as reference or instruction manuals. Some books are a collection of previously published papers dealing with a certain topic, while others may basically provide large sets of data or examples. The Frontiers in Sedimentary Geology series was established both for stu dents and practicing earth scientists who wish to either stay abreast of the most recent ideas or developments or to become familiar with an important topic in the field of sedimentary geology. The series attempts to deal with sub jects that are in the forefront of both scientific and economic interest. The treatment of a subject in an individual volume should be a combination of topi cal, regional, and interdisciplinary approaches. Although these three terms can be defined separately, in reality they should flow into each other. A topical treatment should relate to a major category of sedimentary geology.