Excerpt from Geology of the California Continental Margin: Explanation of the California Continental Margin Geologic Map Series; Interpretive Methods Symbology, Stratigraphic Units, and Bibliography Criteria used here for interpretation of faults are based on descriptions by Greene and others Well-de fined faults: (1) distinct displacement of prominent reflec tors; (2) an abrupt termination of prominent reflectors, or the juxtaposition of intervals of prominent reflectors that have contrasting acoustic characteristics; or (3) an abrupt change in the dips of reflectors across a distinct boundary. Inferred faults: (1) small displacement of prominent reflectors, in which the upper or shallow reflectors may be bent rather than broken; (2) prominent reflectors that are discontinuous, and contrasting seismic characteristics that are present on either side of an acoustically obscure dis turbed zone; or (3) apparent changes in dip on either side of the disturbed zone. Questionable faults (mapped where obscure interrup tions of seismic reflectors are present in the subsurface): (l) a shift in the phase of reflectors; (2) bent or broken reflectors that can be correlated with known faults on other lines; (3) termination of weak reflectors; or (4) any other zone of seismic contrast, especially where the zone appears similar to and is aligned with faults identified on adjacent lines. Some questionable and inferred faults have been mapped where anomalous tapographic lineaments appear to support the continuation of known faults. The orientation of faults is determined principally by correlation from one seismic line to another. Faults are correlated between adjacent lines mainly on the basis of their association with similar structural and seismic fea tures on adjacent profiles. Where fault planes dip more than about the vertical exaggeration common to seis mic-reflection records precludes determining the dip, even though the records clearly indicate that a fault is present. Consequently, faults dipping 35° or more are shown as vertical. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.