i08 GeologicStructures SacramentoValley

This data set was created by scanning the original sheets from (Harwood and Helley, 1987), the sheets were georeferenced individually and the geologic information was digitized using AutoCAD 2006.

The accuracy of the digitized lines was deemed to be within acceptable error tolerances, with the digitized lines accurately matching the original drafted lines. In general, the width of the contact lines on the paper copy, accounting for scale, ranged up to about 20 meters (66 feet). During the original digitization, minor topological mistakes (such as identical rock units on both sides of a lithologic contact or unclosed polygons) and omissions (such as unidentified lithologic units) were applied according to the best available knowledge.