It has been more than a decade since the appearance of the First Edition of this book. Much progress has been made, but some controversies remain. The original idea of Sloss and of Vail (building on the early work of Blackwelder, Grabau, Ulrich, Levorsen and others) that the stratigraphic record could be subdivided into sequences and that these sequences store essential information about basin-forming and subsidence processes remains as powerful an idea as when it was first formulated. The definition and mapping of sequences has become a standard part of the basin analysis process. Subsurface methods make use of advanced seismic-reflection analysis methods, with three-dimensional seismic methods, and seismic geomorphology adding important new dimensions to the analysis.
The main purpose of this book remains the same as it was for the first edition, that is, to situate sequences within the broader context of geological processes so that geoscientists might be better equipped to extract the maximum information from the record of sequences in a given basin or region. The following are the main themes of the book: Central to the concept of the sequence is the deductive model that sequences carry messages about the 'pulse of the earth'. In the early modern period of sequence stratigraphy (the late 1970s and 1980s) the model of global eustasy was predominant, and it was to offer a critique of that model that provided the impetus for developing the first edition of this book.
Model-building has been central to the science of geology from the beginning - it was certainly a preoccupation of such early masters of the science as Lyell, Chamberlin, Barrell and Ulrich. A historical evaluation of the contrasting deductive and inductive approaches to geology has been added to this edition of the book, in order to provide a background in methodology and a historical context. Standard sequence models have become very well described and understood for most depositional settings, and are the subject of several recent texts. Two chapters are provided in this edition in order to outline modern ideas, and to provide a framework of terminology and illustration for the remainder of the book.