Inadequate observation of sedimentary TRUSHKovA and KUKHARENKO'S "Atlas of structures has been responsible for incorrect Placer Minerals." The most comprehensive interpretation of the order of superposition atlas is the "Atlas of Textures and Struc in deformed beds and this has led, in turn, tures of Sedimentary Rocks" edited by A. to gross errors in stratigraphy and structure. V. KHABAKOV (1962). Failure to recognize and utilize those Our Atlas is an outgrowth of our work on structures which indicate direction of cur "Paleocurrents and Basin Analysis," a book rent flow has also led to incorrect, or at in which directional sedimentary structures least incomplete, understanding of basin are described and interpreted with special development. reference to the evolution of sedimentary We believe, therefore, that there is need for basins. That work, however, contains mini a work which constitutes a field guide to the mal photographic material - just enough study of these structures - a book in to give the reader some concept of the sedi which these structures, so difficult to mentary structures described."

The study of paleocurrents, since 1963, is now a very routine part of sedimentology, and more and more such studies are finding use in other fields. Thus it seemed appropriate for us to review post-1963 developments and present them in a compact manner for the interested reader. Instead of rewriting a second edition, which thirteen years later we would organize in a completely dif ferent way, we have brought each chapter up to date with new material up to 1976. A new update supplement has in this edition been inserted after each one of the original chapters. We have stayed close to the original theme of paleocurrents-how to measure them and how to use them to solve geological problems ranging in scale from the hand specimen to the sedimentary basin and beyond. We have used many annotated references and tables to help pre sent this information to the reader. The reader will note that we have cited a few 1962 references - pUblications that appeared too late to be cited in the original 1963 edition. A few times we have also cited a reference which was included in the first edition. These are marked with an asterisk and hence do not appear in the new lists of references. We have been aided by many. In Cincinnati, WANDA OSBORNE and JEAN CARROL did typing and RICHARD SPOHN, the University's geological librarian, was very helpful in obtaining many references to the literature."