Modified Contour-Generalization Procedure As Applied to the Santa Lucia Range, California
Contour generalization is an established procedure for restoring dissected landscapes to predissection forms. The modified generalization procedure herein proposed dispenses with most side-slope contours, leaving upland surfaces suspended at their individual levels. In addition, sequential cartographic patterns permit ready recognition of surfaces, and hachures emphasize abrupt peripheral slopes. Although the primary purpose is to discuss the proposed procedure, the bearing of the final map on the history of the Santa Lucia Range is briefly considered. The origin of the high-level surfaces has not yet been determined, although fragmentary evidence suggests they are probably fluvial. The multiple surfaces were presumably developed in response to changes in the elevation of base level. Simultaneous development of the surfaces due to differential lowering of rocks of varying resistance, independent of base level, is refuted by the similarity of the rock assemblages truncated by the different surfaces. The high surfaces in the northern part of the range are found to be sloping, rather than horizontal as previously supposed. Tilting of the northern area seems indicated. At their elevated southern ends, these surfaces hang above considerably lower terrain. Here, the relative horizontality of at least one extensive surface suggests simple vertical uplift.