Remembering Ridgecrest
Earthquakes can be unsettling.
Feeling the ground beneath you shake and seeing the environment around you roll and rock can leave one feeling wary of what is to come next. This was certainly the case for the community of Ridgecrest, California, on July 4th, 2019, as they experienced a magnitude 6.4 earthquake. As scientists and responders from different agencies and organizations focused their energy on emergency response, another stronger earthquake shook the area about 33 hours later.
In the video, “Remembering Ridgecrest,” USGS scientists recollect how they responded on July 4, 2019, and their most memorable moments during the immediate and subsequent response. This video is only a small snapshot of the many USGS employees who responded, and only begins to allude to the myriad of partner agencies and institutions who were involved. This kind of research and partnership ultimately can help save lives and property.
Related Content
Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?
Release Date: SEPTEMBER 30, 2019
Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
The Ups and Downs of Groundwater Levels After the Ridgecrest, CA Earthquakes
Southern California experienced two large earthquakes in July 2019. Effects from the two earthquakes were observed in several USGS continuous groundwater-level monitoring sites in California, Nevada, and Arizona.
Surface Displacement Observations of the 2019 Ridgecrest, California Earthquake Sequence
Surface rupture associated with the 2019 Ridgecrest, California earthquake sequence includes the dominantly left-lateral and northeast-striking M6.4 rupture and dominantly right-lateral and northwest-striking M7.1 rupture. This data release includes surface-displacement observations of these ruptures made by teams of federal, state, academic, and private sector geologists between July and
Pre-existing features associated with active faulting in the vicinity of the 2019 Ridgecrest, California earthquake sequence
This dataset is composed of linear active tectonic and other relevant features (scarps, deflected drainages, and lineaments and contrasts in topography, vegetation, and ground color) mapped based on high-resolution topography, aerial/satellite imagery, and field observations. The mapping covers the area surrounding the 2019 Ridgecrest, California earthquake surface ruptures.
A High-Resolution Seismic Catalog for the Initial 2019 Ridgecrest Earthquake Sequence
I use template matching and precise relative relocation techniques to develop a high-resolution earthquake catalog for the initial portion of the 2019 Ridgecrest earthquake sequence, from July 4-16, encompassing the foreshock sequence and the first 10+ days of aftershocks following the Mw 7.1 mainshock. Using 13,525 routinely cataloged events as waveform templates, I detect and precise
The predictive skills of elastic Coulomb rate-and-state aftershock forecasts during the 2019 Ridgecrest, California, earthquake sequence
Operational earthquake forecasting protocols commonly use statistical models for their recognized ease of implementation and robustness in describing the short-term spatiotemporal patterns of triggered seismicity. However, recent advances on physics-based aftershock forecasting reveal comparable performance to the standard statistical counterparts...
Mancini, Simone; Segou, Margarita; Werner, Maximillian J; Parsons, Thomas E. Airborne lidar and electro-optical imagery along surface ruptures of the 2019 Ridgecrest earthquake sequence, Southern California
Surface rupture from the 2019 Ridgecrest earthquake sequence, initially associated with the M 6.4 foreshock, occurred on July 4 on a ~17 km long, northeast-southwest oriented, left-lateral zone of faulting. Following the M 7.1 mainshock on July 5 (local time), extensive northwest-southeast-oriented, right-lateral faulting was then also mapped...
Brooks, Benjamin A.; Scharer, Katherine; Hernandez, Janis; Dawson, Timothy E.; Oskin, Mike; Arrowsmith, Ramon; Goulet, Christine A.; Blake, Kelly; Boggs, Matt; Bork, Stephan; Glennie, Craig; Fernandez-Diaz, J.C.; Singhania, Abhinav; Hauser, Darren L.; Sorhus, Sven; Hudnut, Kenneth W.; Brooks, Benjamin A.; Scharer, Katherine M.; Hernandez, Janis L.; Dawson, Timothy E.; Oskin, Michael E.; Arrowsmith, J. Ramon; Goulet, Christine A.; Blake, Kelly; Boggie, Matthew A.; Bork, Stephan; Craig L. Glennie; Fernandez-Diaz, J.C.; Singhania, Abhinav; Hauser, Darren; Sorhus, Sven Dynamic rupture simulations of the M6.4 and M7.1 July 2019 Ridgecrest, California earthquakes
The largest earthquakes of the 2019 Ridgecrest, California, sequence were a M 6.4 left‐lateral rupture followed 34 hr later by a M 7.1 on a perpendicular right‐lateral fault. We use dynamic rupture modeling to address the questions of why the first earthquake did not propagate through the right‐lateral fault in one larger event, whether stress...
Lozos, Julian C.; Harris, Ruth A. The 2019 Ridgecrest, California, earthquake sequence ground motions: Processed records and derived intensity metrics
Following the 2019 Ridgecrest, California, earthquake sequence, we compiled ground‐motion records from multiple data centers and processed these records using newly developed ground‐motion processing software that performs quality assurance checks, performs standard time series processing steps, and computes a wide range of ground‐motion metrics....
Rekoske, John; Thompson, Eric M.; Moschetti, Morgan P.; Hearne, Mike; Aagaard, Brad T.; Parker, Grace Alexandra A high-resolution seismic catalog for the initial 2019 Ridgecrest Earthquake sequence: Foreshocks, aftershocks, and faulting complexity
I use template matching and precise relative relocation techniques to develop a high-resolution earthquake catalog for the initial portion of the 2019 Ridgecrest earthquake sequence, from July 4-16, encompassing the foreshock sequence and the first 10+ days of aftershocks following the Mw 7.1 mainshock. Using 13,525 routinely cataloged events as...
Shelly, David R. Caltech/USGS Southern California Seismic Network (SCSN) and Southern California Earthquake Data Center (SCEDC): Data availability for the 2019 Ridgecrest sequence
The 2019 M6.4 and M7.1 Ridgecrest earthquake sequence occurred in the eastern California shear zone (ECSZ). The mainshock ruptured the Little Lake fault zone and aftershocks extended from the Garlock fault in the south, to the southern end of the 1872 M7.5 Owens Valley earthquake rupture in the north. We present data from the Southern California...
Hauksson, Egill; Yoon, Clara; Yu, Ellen; Andrews, Jennifer; Alvarez, Mark; Bhadha, Rayo; Thomas, Valerie Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence
The Ridgecrest Earthquake sequence included a foreshock event on July 4 2019 (M6.4) and a M7.1 mainshock event on July 5 2019. These events occurred in the Eastern California Shear Zone, near Indian Wells Valley, south of China Lake and west of Searles Valley. GEER has partnered with several organizations to collect perishable data and document...
Stewart, Jonathan P.; Brandenberg, Scott J; Wang, Pengfei; Nweke, Chukwuebuka C; Hudson, Kenneth; Mazzoni, Silvia; Bozorgnia, Yousef; Hudnut, Kenneth W.; Davis, Craig A.; Ahdi, Sean K; Zareian, Farzin; Fayaz, Jawad; Koehler, Richard D; Chupik, Colin; Pierce, Ian; Williams, Alana; Akciz, Sinan; Hudson, Martin B; Kishida, Tadahiro; Brooks, Benjamin A.; Gold, Ryan D.; Ponti, Daniel J.; Scharer, Katherine; McPhillips, Devin; Duross, Christopher; Ericksen, Todd; Hernandez, Janis; Patton, Jay; Olson, Brian; Dawson, Timothy E.; Treiman, Jerome; Blake, Kelly; Buchhuber, Jeffrey; Madugo, Chris L M; Sun, Joseph; Donnellan, Andrea; Lyzenga, Greg; Conway, Erik Observation of the seismic nucleation phase in the Ridgecrest, California, earthquake sequence
Near-source observations of five M 3.8-5.2 earthquakes near Ridgecrest, California are consistent with the presence of a seismic nucleation phase. These earthquakes start abruptly, but then slow or stop before rapidly growing again toward their maximum rate of moment release. Deconvolution of instrument and path effects by empirical Green's...
Ellsworth, W.L.; Beroza, G.C.
Catalog Shows Complex Rupturing During 2019 Ridgecrest Sequence
The 2019 Ridgecrest earthquake sequence, which startled nearby California residents over the 4 July holiday with magnitude 6.4 and magnitude 7.1 earthquakes, included 34,091 earthquakes overall, detailed in a high-resolution catalog created for the sequence.
Image of the Week - A Tear in the Mojave
Satellite imagery shows the rupture and shifting of land near Ridgecrest, CA from the July 2019 earthquakes.
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS Pasadena Earthquake Response Coordinator surveys displaced rocks near the southern end of the surface rupture of the 5 July 2019 M7.1 Ridgecrest earthquake. USGS photograph. Photo credit: Sue Hough, USGS
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
Kate Scharer examining striations along fault scarp while completing GPS survey of fault rupture. Here the fault has about 2.6 m of horizontal displacement and 0.5 m of vertical. The rake of the striations is 47 degrees. Photo credit: Jamie Delano, USGS
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS scientist Jaime Delano, observes a sand blow caused by liquefaction during the M7.1 Ridgecrest earthquake. Photo credit: Chris DuRoss
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS scientist Jessie Thompson Jobe measures fault offset at the site of the Ridgecrest earthquake sequence rupture. Photo credit: Chris DuRoss, USGS
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS Geophysicists Elizabeth Cochran and Nick VanDerElst install a seismometer on the base Photo credit: Ben Brooks, USGS
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS scientist Jessie Thompson Jobe collects and records information on earthquake surface ruptures observed along a roadway following the Ridgecrest earthquake sequence. Photo credit: Ryan Gold (USGS)
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS scientist Kate Scharer provides Commanding Officer CAPT Paul Dale (Navy) with the field team’s initial mapping product, showing the surface fault rupture at Naval Air Weapons Station China Lake (NAWSCL) as well as the temporarily deployed seismic and GPS sensors that were rapidly deployed. Field data were provided by California Geological Survey (CGS) and USGS (from
...
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
Geologists with USGS, the California Geological Survey (CGS) and Naval Air Weapons Station China Lake (NAWS) worked together in response to the Ridgecrest earthquake sequence in California that occurred July 4-6, 2019. The earthquakes were large enough that the fault rupture reached the earth’s surface. Here, research geologist Belle Philibosian was part of a USGS field
...
2019 Ridgecrest Earthquake Sequence: July 4, 2019–July 16, 2019
3,557 earthquakes recorded since July 4, 2019 above Magnitude 2
M6.4 12km W of Searles Valley, CA
2019-07-04 17:33:49 (UTC)
51,000+ responses via Did You Feel It?
M7.1 18km W of Searles Valley, CA
2019-07-06 03:19:53 (UTC)
42,000+ responses via Did You Feel It?
631 M3+
...
Women in Science - Responding to Ridgecrest, CA earthquake July 2019
USGS Geologists Beth Haddon and Josie Nevitt measure fault displacement along the principal rupture in the Southern California desert near Ridgecrest. Photo credit: Ben Brooks, USGS
Animation of Ridgecrest Foreshock Seq up to M7.1 (Prelim. Results)
This animation shows preliminary results from precise relocation of the Ridgecrest foreshock sequence, up to the the time of occurrence of the M 7.1 mainshock. The animation begins in a map view and then transitions into a rotating vertical slice. Earthquakes are colorcoded by time of occurrence, with early events in dark blue and later events (up to the M 7.1) in dark