Between May 25 (12:00 AM PST) and May 31 (11:59 PM) there were 61 earthquakes in California of magnitude 2.0 or larger. 🔸56 quakes between magnitude 2.0 - 2.9 🔸5 quakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.9 W of Petrolia, CA. cadoc.maps.arcgis.com/apps/dashboa...

Interested in learning more about the newly released Sierra Nevada Earth Science Atlas? Read about it in California Geology Magazine! www.conservation.ca.gov/cgs/document...

Between May 4 (12:00 AM PST) and May 10 (11:59 PM) there were 183 earthquakes in California of magnitude 2.0 or larger. 🔸153 earthquakes between M2.0 - 2.9 🔸25 earthquakes between M3.0 - 3.9 🔸5 earthquakes between M4.0 - 4.9 The largest earthquake was a M4.9 WSW of Crescent City, CA

The newly released Sierra Nevada Atlas is a collection of maps, geospatial datasets, and associated text that presents geologic map layers, geophysical layers, economic geology layers, neotectonic features, and geochronology for the Sierra Nevada. www.conservation.ca.gov/cgs/sierra-n...

Between April 27 (12:00 AM PST) and May 3 (11:59 PM) there were 43 earthquakes in California of magnitude 2.0 or larger. 🔸34 earthquakes between magnitude 2.0 - 2.9 🔸9 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.7 near Petrolia, CA

NEW RELEASE! Sierra Nevada Earth Science Atlas The Sierra Nevada Earth Science Atlas provides the most detailed geologic framework mapping of the Sierra Nevada that has ever been made. www.conservation.ca.gov/cgs/sierra-n...

NEW RELEASE! Map Sheet 52: Aggregate Sustainability in California Aggregate materials like sand, gravel, and crushed stone are essential to modern society, both to maintain the existing infrastructure and to provide for new construction. www.conservation.ca.gov/cgs/minerals...

Between April 20 (12:00 AM PST) and April 26 (11:59 PM) there were 40 earthquakes in California of magnitude 2.0 or larger. 🔸30 quakes between M2.0 - 2.9 🔸9 quakes between M3.0 - 3.9 🔸1 quake between M4.0 - 4.9 The largest earthquake was a magnitude 4.1 near Petrolia, CA.

Between April 13 (12:00 AM PST) and April 19 (11:59 PM) there were 28 earthquakes in California of magnitude 2.0 or larger. 🔸26 earthquakes between magnitude 2.0 - 2.9 🔸2 earthquake between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.5 near Ludlow, CA.

@cageosurvey.bsky.social is hiring a Supervising Engineering Geologist to lead the Forest & Watershed Program--oversee THP reviews, landslide/GIS analysis, watershed restoration, & a team of geologists. Apply by 4/17/26: calcareers.ca.gov/CalHrPublic/Jobs/JobPosting.aspx?JobControlId=512006

Between April 6 (12:00 AM PST) and April 12 (11:59 PM) there were 39 earthquakes in California of magnitude 2.0 or larger. 🔸38 earthquakes between magnitude 2.0 - 2.9 🔸1 earthquake between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.2 near Trinidad, CA.

Between March 30 (12:00 AM PST) and April 5 (11:59 PM) there were 47 earthquakes in California of magnitude 2.0 or larger. 🔸41 quakes between M2.0 - 2.9 🔸5 quakes between M3.0 - 3.9 🔸1 quakes between M4.0 - 4.9 The largest earthquake was a magnitude 4.6 near Boulder Creek, CA.

Joshua Tree National Park is renowned for its forests of Joshua trees, its namesake species. Though less well known but similarly recognizable, the geology and geomorphology are equally important to the iconic landscape that attracts millions of visitors each year.

The mission of the California Geological Survey is to provide scientific products and services about the state’s geology, seismicity, forests and watersheds, and mineral resources that affect the health, safety, and business interests of the people of California.

Between March 23 (12:00 AM PST) and March 29 (11:59 PM) there were 46 earthquakes in California of magnitude 2.0 or larger. 🔸41 earthquakes between M2.0 - 2.9 🔸4 earthquakes between M3.0 - 3.9 🔸1 earthquake between M4.0 - 4.9 The largest earthquake was a magnitude 4.1 near Ludlow, CA.

A tsunami can move more than water. 🌊 Understanding how #tsunami debris and sediment moves and where it might end up is a critical part of preparing for and recovery from a tsunami. 🔍Explore more: www.conservation.ca.gov/cgs/tsunami/...

The @CAGeoSurvey is working with @caloes.bsky.social to create tools and information to help the public & emergency officials understand their tsunami risk & how to prepare for the next tsunami. Learn more about our Cal OES tsunami partner here: www.youtube.com/watch?v=tq_p... #tsunami

🌊 #Tsunami are a series of powerful waves often caused by underwater earthquakes or landslides. As tsunami waves approach the shore, they build in size, their currents intensify, and they become a threat to life & property. Go to tsunami.ca.gov for more information.

It’s Tsunami Awareness Week! California Tsunami Hazard Area Maps & Data are prepared to assist citizens, cities, and counties in identifying their tsunami hazard. tsunami.ca.gov/maps #TsunamiReady @CalConservation Be sure to have a tsunami plan and know your zone. www.tsunamizone.org/knowyourzone/

Between March 16 (12:00 AM PST) and March 22 (11:59 PM) there were 48 earthquakes in California of magnitude 2.0 or larger. 🔸41 earthquakes between magnitude 2.0 - 2.9 🔸7 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.7 near Petrolia, CA.

Between March 9 (12:00 AM PST) and March 15 (11:59 PM) there were 43 earthquakes in California of magnitude 2.0 or larger. 🔸40 earthquakes between magnitude 2.0 - 2.9 🔸3 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.3 near Rio Dell, CA.

Between March 2 (12:00 AM PST) and March 8 (11:59 PM) there were 52 earthquakes in California of magnitude 2.0 or larger. 🔸47 earthquakes between magnitude 2.0 - 2.9 🔸5 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.6 near The Geysers, CA.

Between February 23 (12:00 AM PST) and March 1 (11:59 PM) there were 44 earthquakes in California of magnitude 2.0 or larger. 🔸39 earthquakes between magnitude 2.0 - 2.9 🔸5 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.6 near Johannesburg, CA.

The California Geological Survey is thrilled to announce the release of the newest edition of California Geology Magazine! www.conservation.ca.gov/cgs/document...

Between February 16 (12:00 AM PST) and February 22 (11:59 PM) there were 63 earthquakes in California of magnitude 2.0 or larger. 🔸60 quakes between M2.0 - 2.9 🔸2 quakes between M3.0 - 3.9 🔸1 quakes between M4.0 - 4.9 The largest earthquake was a magnitude 4.2 near Cobb, CA.

Between February 2 (12:00 AM PST) and February 8 (11:59 PM) there were 36 earthquakes in California of magnitude 2.0 or larger. 🔸97 earthquakes between M2.0 - 2.9 🔸8 earthquakes between M3.0 - 3.9 🔸2 earthquakes between M4.0 - 4.9 The largest earthquake was a magnitude 3.7 west of Petrolia, CA.

Between January 26 (12:00 AM PST) and February 1 (11:59 PM) there were 36 earthquakes in California of magnitude 2.0 or larger. 🔸31 earthquakes between magnitude 2.0 - 2.9 🔸5 earthquake between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.4 near San Ramon, CA.

Between January 19 (12:00 AM PST) and January 25 (11:59 PM) there were 83 earthquakes in California of magnitude 2.0 or larger. 🔸70 earthquakes between M2.0 - 2.9 🔸10 earthquake between M3.0 - 3.9 🔸3 earthquake between M4.0 - 4.9 The largest earthquake was a magnitude 4.9 near Indio, CA.

Between January 12 (12:00 AM PST) and January 20 (8:30 AM) there were 85 earthquakes in California of magnitude 2.0 or larger. 🔸65 earthquakes between M2.0 - 2.9 🔸16 earthquake between M3.0 - 3.9 🔸4 earthquake between magnitude 4.0 - 4.9 The largest earthquake was a magnitude 4.9 near Indio, CA.

32 years ago, at 4:31 AM, a magnitude 6​.7 earthquake struck southern California. This quake, centered in Northridge, caused 57 fatalities and injured thousands.

Between January 5 (12:00 AM PST) and January 11 (11:59 PM) there were earthquakes in California of magnitude 2.0 or larger. 🔸38 earthquakes between M2.0 - 2.9 🔸4 earthquake between M3.0 - 3.9 🔸1 earthquake between M4.0 - 4.9 The largest earthquake was a magnitude 4.2 near Cloverdale, CA.

The California Geological Survey offers a variety of interactive web maps, including geologic and geohazard maps, mineral resource maps, and earthquake regulatory zone maps. These maps can be found here: maps.conservation.ca.gov/cgs/#datalist

Geologic mapping of California continues with the Regional Geologic & Landslide Mapping Program. Maps include statewide geologic and fault activity maps, geologic atlas and regional geologic map series, and offshore continental margin maps. www.conservation.ca.gov/cgs/rgm/prog...

Between December 29 (12:00 AM PST) and January 4 (11:59 PM) there were 52 earthquakes in California of magnitude 2.0 or larger. 🔸50 earthquakes between M2.0 - 2.9 🔸1 earthquake between M3.0 - 3.9 🔸1 earthquake between M4.0 - 4.9 The largest earthquake was a magnitude 4.9 near Susanville, CA.

135 years have passed since the preparation of the 1891 Preliminary Mineralogical and Geological Map of the State of California. This webpage walks you through the history and evolution of geologic maps of California. www.conservation.ca.gov/cgs/rgm/hist...

Geologic mapping in California began about 180 years ago. The first geologic mapping in the State was done by Lieutenant Edward Belcher, a British naval officer. Although Belcher did the surveying for the map in 1826, it was not published until 1839. www.conservation.ca.gov/cgs/rgm/hist...

In 1851 Dr. John B. Trask was named as “State Geologist”. Today, the CA State Geologist is Jeremy Lancaster. He leads the @cageosurvey.bsky.social in providing scientific products and services about the state's geology, seismology, geohazards, and minerals. www.conservation.ca.gov/cgs/about/hi...

Between December 22 (12:00 AM PST) and December 28 (11:59 PM) there were 61 earthquakes in California of magnitude 2.0 or larger. 🔸57 quakes between M2.0 - 2.9 🔸3 quakes between M3.0 - 3.9 🔸1 quake between M4.0 - 4.9 The largest earthquake was a magnitude 4.7 near Susanville, CA.

California Geotour is an index of field trip information for people interested in visiting California's world-famous geologic features. This site contains geologic information, photographs, maps & directions for interesting geologic locations across the state. www.conservation.ca.gov/cgs/californ...

Between December 15 (12:00 AM PST) and December 21 (11:59 PM) there were 94 earthquakes in California of magnitude 2.0 or larger. 🔸83 quakes between M2.0 - 2.9 🔸11 quakes between M3.0 - 3.9 The largest earthquake was a magnitude 3.9 near San Ramon, CA.

Between December 8 (12:00 AM PST) and December 14 (11:59 PM) there were 102 earthquakes in California of magnitude 2.0 or larger. 🔸90 quake between M2.0 - 2.9 🔸11 quake between M3.0 - 3.9 🔸1 quake between M4.0 - 4.9 The largest earthquake was a M4.0 near Glen Ellen, CA.

Between December 1 (12:00 AM PST) and December 7 (11:59 PM) there were 44 earthquakes in California of magnitude 2.0 or larger. 🔸40 earthquakes between magnitude 2.0 - 2.9 🔸4 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.4 near Fortuna, CA.

Did you know that Serpentinite is California’s state rock? Serpentinite is green to black & is often mottled with light & dark colored areas. It’s mainly found in central & northern California in the Coast Ranges, Klamath Mountains & Sierra Nevada foothills. www.conservation.ca.gov/cgs/Document...

Between November 24 (12:00 AM PST) and November 30 (11:59 PM) there were 66 earthquakes in California of magnitude 2.0+. -50 quakes between M2.0 - 2.9 -15 quakes between M3.0 - 3.9 -1 quakes between M4.0 - 4.9 The largest quake was a magnitude 4.0 near San Juan Bautista.

Did you know that Benitoite is the California state gem? Benitoite can occur in rich blue crystals that are as striking and flawless as the finest sapphires. Gem quality benitoite is found only in a small area of San Benito County, California. 🧪 ⚒️ www.conservation.ca.gov/cgs/Document...

Are you traveling over the holiday weekend? Be sure to check out some of California’s “Geo Gems” - notable geologic features in California state parks. These geologic wonders illustrate the legacy and continuing geologic evolution of California.   www.parks.ca.gov?page_id=29631

Between November 17 (12:00 AM PST) and November 23 (11:59 PM) there were 41 earthquakes in California of magnitude 2.0 or larger. -36 quakes between M2.0 - 2.9 -4 quakes between M3.0 - 3.9 -1 quake between M4.0 - 4.9 The largest earthquake was a M4.1 near Templeton, CA.

Between November 10 (12:00 AM PST) and November 16 (11:59 PM) there were 37 earthquakes in California of magnitude 2.0 or larger. 🔸33 earthquakes between magnitude 2.0 - 2.9 🔸4 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.5 near Vallejo, CA.

Between November 3 (12:00 AM PST) and November 9 (11:59 PM) there were 50 earthquakes in California of magnitude 2.0 or larger. 🔸45 quakes between magnitude 2.0 - 2.9 🔸5 quakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.8 near San Ramon, CA.

Between October 27 (12:00 AM PST) and November 2 (11:59 PM) there were 43 earthquakes in California of magnitude 2.0 or larger. 🔸39 earthquakes between magnitude 2.0 - 2.9 🔸4 earthquakes between magnitude 3.0 - 3.9 The largest earthquake was a magnitude 3.5 west of Petrolia, CA.