Preliminary quaternary geologic maps of Santa Clara Valley, Santa Clara, Alameda, and San Mateo counties, California: A digital database
This digital map database, which is compiled from previouslyunpublished and open-filed U.S. Geol. Survey reports (Wesling andHelley, 1989), represents the general distribution and identity ofQuaternary deposits in eight 7.5 minute quadrangles in the southernSan Francisco Bay region, California.
San Francisco Bay Region landslide folio part E - Map of debris-flow source areas in the San Francisco Bay region, California
This map identifies the principal areas in the San Francisco Bayregion that are likely to produce debris flows, which are alsocalled "mudslides." Debris flows that occur in the bay region arefast-moving downslope flows of mud that may include rocks,vegetation, and other debris. These flows begin during intenserainfall as shallow landslides on steep slopes. The rapid movementand sudden arrival of debris flows pose a hazard to life andproperty during and immediately following the triggering rainfall.Debris flows in a given storm originate from a number of sourcesscattered throughout steep parts of the landscape, as shown infigure 1 (on map sheet; files sfbr- df.ps, al-df.ps, etc.). Duringsubsequent storms, new debris...
General distribution of geologic materials in the southern San Francisco Bay region, California: A digital map database
The ssfb_m1 digital map database, which is compiled from 1970'svintage sources, represents the general distribution and identityof geologic materials in the southern San Francisco Bay region,California, west of the Calaveras fault. It is not a geologic map,because it does not address the geologic structure or thestratigraphic organization of the map units in a systematic way.Instead, it is directed at the distribution and character of thegeologic materials following the pattern of its progenitors,Wentworth and others (1985) and Ellen and Wentworth (in press).Consultation of these reports and the other compilation sources willaid in using the database.
Preliminary geologic map emphasizing bedrock formations in Alameda County, California: A digital database
This Open-File report is a digital geologic map database of the Alameda County, California.
The Little Piute Mountains in the eastern Mojave Desert expose a seriesof folds and thrust faults involving metamorphosed Paleozoic strata (Millerand others, 1982; Stone and others, 1983). The Little Piute Mountains Digital database contains digital geologic and geographic information for the study area. The geology was mapped at a scale of 1:8,000, and the topographic information was input from the Little Piute Mountains, CA 1:24,000 quadrangle.
Geologic map of the Hayward fault zone, Contra Costa, Alameda, and Santa Clara Counties, California: A digital database
This digital map database, compiled from previously open- filed U.S.Geological Survey reports (Graymer and others, 1994, Graymer,Jones, and Brabb, 1994) and unpublished data, represents thegeneral distribution of rocks and faults in the Hayward fault zone.As described in this report, the Hayward fault zone is a zone ofhighly deformed rocks which trends north 30 degrees west from anarea southeast of San Jose to the San Pablo Bay, and ranges inwidth from 2 to 10 kilometers. Although historic earthquakeactivity has been concentrated in the western part of the zone, thezone as a whole reflects oblique right-lateral and compressivedeformation along a significant upper crustal break over the past10 million years or more....
Preliminary geologic map emphasizing bedrock formations in Contra Costa County, California: A digital database
This digital map database, which is compiled from previouslypublished and unpublished sources combined with new mapping,represents the general distribution and identity of bedrock in ContraCosta County, California.