Welcome to the California Department of Conservation

Welcome to CGS's Information Warehouse.

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Regulatory Maps

Alquist-Priolo Earthquake Fault Zoning Act (1972) and the Seismic Hazards Mapping Act (1990) direct the State Geologist to delineate regulatory "Zones of Required Investigation" to reduce the threat to public health and safety and to minimize the loss of life and property posed by earthquake-triggered ground failures. Cities and counties affected by the zones must regulate certain development "projects" within them. These Acts also require sellers of real property (and their agents) within a mapped hazard zone to disclose at the time of sale that the property lies within such a zone.

Click on the following link for more information on the Alquist-Priolo Earthquake Fault Zoning Act.

Click on the following link for more information on the Seismic Hazards Mapping Act.

NOTE: Fault Evaluation Reports are available for those areas covered by a Regulatory Map however there are reports available for areas outside the Regulatory map boundary. For a complete set of maps available for purchase on CD please contact the CGS Library

View Regulatory Maps

Landslide Maps

Since the 1960's, the California Geological Survey (CGS) has produced numerous maps that show landslide features and delineate potential slope-stability problem areas. Preparation of these maps has been episodic, often driven by landslide disasters and subsequent legislative mandates. Many CGS landslide maps and related products have been produced for local or state agencies in response to their specific needs.

This index includes landslide maps produced over many years for a variety of purposes. See the description of CGS landslide programs for details of some of the major programs and types of landslides and landslide maps.

View Landslide Maps

Tsunami Maps

Tsunami inundation maps were prepared to assist cities and counties in identifying their tsunami hazard. They are intended for local jurisdictional, coastal evacuation planning uses only. The inundation line represents the maximum considered tsunami run up from a number of extreme, yet realistic, tsunami sources.

Click on the following link for additional information on Tsunami Inundation Maps.

View Tsunami Maps


Mineral Land Classification studies are produced by the State Geologist as specified by the Surface Mining and Reclamation Act (SMARA, PRC 2710 et seq.) of 1975. To address mineral resource conservation, SMARA mandated a two-phase process called classification-designation. Classification is carried out by the State Geologist and designation is a function of the State Mining and Geology Board. The classification studies contained here evaluate the mineral resources and present this information in the form of Mineral Resource Zones.

The objective of the classification-designation process is to ensure, through appropriate local lead agency policies and procedures, that mineral materials will be available when needed and do not become inaccessible as a result of inadequate information during the land-use decision-making process.

View SMARA Maps

The warehouse currently hosts a collection of over 3,100 maps, 1,400 reports and 600 Geographic Information System (GIS) datasets representing a portion of CGS's publications produced over its 150+ year history. Additional publications, both old and new, will be added in the future. Digital copies (in pdf format) are available for free download. For those publications with GIS data, the GIS files are also available. Because many of these maps and reports were produced before the availability of GIS, not all products have GIS files available.

This site allows you to search CGS's collection of digitized maps and reports by geographic region. The products are organized by topic into several categories (Regulatory Maps, Landslide Maps, Tsunami Maps & SMARA Maps). As additional products are added, more categories may be added as well.

Start exploring CGS's digital information products by clicking on one of the topic tabs above or icons below.

(The images above help illustrate the distribution of files/formats across the 4 map categories.)

Please contact CGS for any questions, comments or suggestions.