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Research about Mendocino County, Sonoma County, California

Source-linked reports with geographic coverage including Mendocino County, Sonoma County, California.

4 recordsLinked to original sources
USGS2006

The San Andreas fault in Sonoma and Mendocino counties

This two-day trip explores the northern San Andreas fault in the Gualala area between Fort Ross and Point Arena (Fig. 1 ). The first stop overlooks the Golden Gate Bridge and includes a discussion of its in-progress seismic retrofit. Several subsequent stops are at paleoseismic sites on the San Andreas fault. The stop at Annapolis Road includes a short hike along the fault through the redwood forest. This section of the fault is locked and has not moved since the 1906 earthquake. Additional stops visit Quaternary marine terraces and include discussion of associated tectonic deformation.

California↗
USGS2003

Water temperature, streamflow, and ground-water elevation in and adjacent to the Russian river between Hopland and Guerneville, California from 1998-2002

Temperature, water level elevation, stage height, and river discharge data for this report were collected in and adjacent to the Russian River from Hopland to Guerneville, CA over a four-year period from 1998 to 2002 to establish baselines for long-term water quality, water supply and habitat. Data files presented in this report were collected by the USGS and the Sonoma County Water Agency's Engineering Resource and Planning, and Natural Resource Divisions. Temperature data were collected in single-channel submersible microloggers or temperature data were collected simultaneously with water-elevation data in dual-channel down-hole data loggers. Stream stage and streamflow data were collected at USGS stream gaging stations located near Hopland, Healdsburg, and Guerneville over a 130 km reach of the Russian River. During the period of record stream flow ranged from 3 to 1458 m3/s. Stream temperature ranged from 8 to 29 oC while groundwater temperature ranged from 10 to 38 oC. Stream stage varied 5 m seasonly, while ground-water level varied 19 m over the same time scale.

California↗