2014 South Napa earthquake

Last updated

2014 South Napa earthquake
2014 South Napa quake - Stones Fallen From Face of Sam Kee - 1 (15014707736).jpg
Damage to the Sam Kee Laundry Building
Relief map of California.png
Bullseye1.svg
Green pog.svg
Napa
UTC  time2014-08-24 10:20:44
ISC  event 610572079
USGS-ANSS ComCat
Local dateAugust 24, 2014 (2014-08-24)
Local time03:20:44 PDT (UTC-7)
Magnitude6.0 Mw [1]
Depth7 mi (11 km) [1]
Epicenter 38°13′N122°19′W / 38.22°N 122.31°W / 38.22; -122.31 Coordinates: 38°13′N122°19′W / 38.22°N 122.31°W / 38.22; -122.31 [1]
Fault West Napa Fault
Type Strike-slip [1]
Areas affected North Bay (San Francisco Bay Area)
California, United States
Total damage$362 million–$1 billion [2] [3]
Max. intensity VIII (Severe) [1]
Peak acceleration0.61 g [4]
Casualties1 killed [5]
about 200 injured [6]

The 2014 South Napa earthquake occurred in the North San Francisco Bay Area on August 24 at 03:20:44 Pacific Daylight Time. At 6.0 on the moment magnitude scale and with a maximum Mercalli intensity of VIII (Severe), the event was the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake. The epicenter of the earthquake was located to the south of Napa and to the northwest of American Canyon on the West Napa Fault. [7]

Contents

Total damage in the southern Napa Valley and Vallejo areas was in the range of $362 million to $1 billion, with one person killed and 200 injured. Other aspects of the event included an experimental earthquake warning system that alerted seismologists several seconds before the damaging shear waves arrived, temporary changes in springs and wells, and the potential for postseismic fault creep.

Tectonic setting

The San Andreas Fault System is an active plate boundary comprising right-lateral strike-slip faults that runs nearly the length of California. This network of faults trends north-northwest in the area of the West Napa Fault, where it is 50 miles (80 km) wide from west to east. The West Napa Fault transfers slip between a group of related faults (including the Concord Fault and the Calaveras Fault) called the Contra Costa Shear Zone, which was assigned a maximum slip rate of 1mm/yr in the third Uniform California Earthquake Rupture Forecast. The authors of a separate study that focused on Global Positioning System data gave an estimated slip rate of 4±3mm/yr for the West Napa Fault. [8] [9]

Earthquake

The mainshock was magnitude 6.0, with a depth of 11.3 km. [1] The United States Geological Survey (USGS) estimated that 15,000 people experienced severe shaking, 106,000 people felt very strong shaking, 176,000 felt strong shaking, and 738,000 felt moderate shaking. [10] The earthquake lasted 10 to 20 seconds, depending on location. [11] At least twelve aftershocks followed, including one of magnitude 3.9. [12] The earthquake was the largest earthquake in the Bay Area since the magnitude 6.9 1989 Loma Prieta earthquake. [11] Governor Jerry Brown declared a state of emergency due to the severe damage and the possibility of aftershocks. [13] President Obama declared a major disaster for Napa and Solano counties. [14]

Damage

Several older commercial buildings in downtown Napa showed signs of extensive external damage even though many had been retrofitted for earthquake safety protection. [10] The Goodman Library, Napa County Courthouse Plaza, Sam Kee Laundry Building, Downtown U.S. Post Office, Alexandria Hotel and Annex, Native Sons of the Golden West building, [15] First United Methodist Church, and First Presbyterian Church all suffered moderate to extensive damage. [6]

Damaged Alexandria Square building in Napa 2014 South Napa eathquake Alexandria Square building.jpg
Damaged Alexandria Square building in Napa

All of these buildings are listed on the National Register of Historic Places, as is the Thomas Earl House, a historic residence that was badly damaged. Although the structure of the Uptown Theater was determined to be sound, the building was red-tagged due to damage to the theater's ceiling. [16] Several newer commercial buildings also suffered damage. [17] Six major fires broke out, [10] and four homes in Napa Valley Mobile Home Park located in north Napa were destroyed. Firefighters were hampered in their efforts to fight this fire by a broken water main. [18] In Vallejo, several hundred storefront windows shattered and many building walls suffered extensive damage. A water main on Mare Island broke. [19]

Following the first round of building inspections by the City of Napa inspectors, a total of 613 structures had been tagged; 113 were red-tagged and 500 had been yellow-tagged. [20] Pavement on several roads in Napa, Solano and Sonoma Counties buckled and cracked during the quake. [21]

Within days, County officials estimated the damage at $362 million. [2] According to an early estimate by the USGS, the economic costs to Napa County may go as high as $1 billion. [3] Several wineries including Hess Collection and Trefethen Vineyards suffered damage to buildings and infrastructure. Several wine storage facilities also suffered damage and loss of property. [22] Estimates of the damage to the wine industry were downgraded to between $80 and $100 million in a September 5, 2014 report from Silicon Valley Bank to the Napa County Board of Supervisors. [23]

On September 16, 2014 in a report to the Napa City Council, members were briefed on the status of damage sustained. City Staff reported that 156 commercial and residential structures had been red-tagged and 1398 had been yellow-tagged. It was also reported that the estimate for damage to the City's infrastructure had reached $57.9 million. This total included repairs made to 144 water mains, repairs or replacement of a compromised water tank in Browns Valley that is part of the City's water system and repair of 294 locations where streets and sidewalks had been damaged. [24]

USGS ShakeMap for the event Shake Intensity - 2014 South Napa Earthquake.jpg
USGS ShakeMap for the event

Injuries

About 200 injured people were treated at Queen of the Valley Medical Center in Napa. [6] Thirteen of those injured were admitted. Many of the injuries were lacerations and abrasions from fallen debris. [10] At least six of the injuries were classified as critical. [25] In Vallejo, 49 people were injured, including two who were hospitalized. [19] CNN reported one individual still in critical condition, later discovery determined as a 58-year-old male who went through two surgeries, awakening four days later in ICU to discover it was going to take him approximately two years to learn how to walk again. One person died September 5 as a result of injuries from the quake. [26] [27]

Recovery

Several of the historic buildings damaged in the earthquake were repaired. The Uptown Theater was the first to reopen on November 9, 2014. [28] The congregation of the First Presbyterian Church moved back into the sanctuary in July 2016 following repairs and restoration at a cost of $850,000. [29] The United Methodist Church received $2.2 million in repairs and upgrades and reopened the doors to its congregation in November 2015. [30] [31] A $1.75 million contract to repair damage to the Goodman Library was awarded in January 2017. [32] The United States Postal Service determined that repairing the building would be too costly and sold it to a developer for $2 million. [33] An $11.6 million contract for restoration of the courthouse was awarded by Napa County in August 2017. [34] The heavily damaged Trefethen Vineyard Eschol building was restored from earthquake damage following over two years of repairs and improvements. [35]

Hydrologic effects

The event was credited with large, temporary increases in the water flow of several nearby streams, including Carriger Creek, Calabasas Creek, Felder Creek, Sonoma Creek, Tulocay Creek, Green Valley Creek, and Wild Horse Creek. In addition, the water levels of several wells in the Sonoma Valley rose suddenly at the time of the quake, in one instance by 5 feet (1.5 m). [36] [37]

Earthquake warning

An experimental earthquake warning system being developed by the Berkeley Seismological Laboratory issued a warning upon detecting the P-waves five seconds before the slower, more destructive S-waves arrived in Berkeley. Initially this was reported to be a 10-second warning in Berkeley, [38] [39] but revised information indicates only a 5-second warning was provided. [40] This means the S-waves had already arrived in Napa and Vallejo when the warning was issued.

Seismic Warning Systems, Inc., a private earthquake warning company based in Scotts Valley, CA, had installed on-site warning systems at five fire stations in Vallejo in 2002 and 2003. [41] These systems commanded the bay doors to open at these fire stations between 1.7 and 2.4 seconds before the S-waves arrived at each fire station.

Earthquake warning systems could potentially give people time to take cover in the event of a quake, preventing injuries caused by falling debris, automatically stopping trains or shutting off gas lines. The system being developed at the Berkeley Seismological Laboratory (called ShakeAlert) in conjunction with the United States Geological Survey, the California Institute of Technology and the University of Washington, will eventually cover the entire West Coast. The system would cost $80 million in funding to run for five years in California, or $120 million for the whole West Coast. [42] In December 2014, United States Congress approved a $5 million allocation as part of the Consolidated Appropriations Act, 2014 in order to expand funding for development of the system. [43]

See also

Related Research Articles

<span class="mw-page-title-main">Napa Valley Opera House</span> United States historic place

The Napa Valley Opera House is a theatre in Napa, California, it opened on February 13, 1880, with a production of Gilbert and Sullivan's HMS Pinafore.

<span class="mw-page-title-main">Trefethen Vineyards</span>

Trefethen Family Vineyards is a winery in Napa Valley. It was established in 1968.

<span class="mw-page-title-main">2003 San Simeon earthquake</span> Earthquake in California

The 2003 San Simeon earthquake struck at 11:15 PST on December 22 on the Central Coast of California, about 7 miles (11 km) northeast of San Simeon. Probably centered in the Oceanic fault zone within the Santa Lucia Mountains, it was caused by thrust faulting and the rupture propagated southeast from the hypocenter for 12 miles (19 km).

The 1952 Kern County earthquake occurred on July 21 in the southern San Joaquin Valley and measured 7.3 on the moment magnitude scale. The main shock occurred at 4:52 am Pacific Daylight Time, killed 12 people, injured hundreds more and caused an estimated $60 million in property damage. A small sector of damage near Bealville corresponded to a maximum Mercalli intensity of XI (Extreme), though this intensity rating was not representative of the majority of damage. The earthquake occurred on the White Wolf Fault near the community of Wheeler Ridge and was the strongest to occur in California since the 1906 San Francisco earthquake.

<span class="mw-page-title-main">Puente Hills Fault</span> Geological fault in California, United States

The Puente Hills Fault is an active geological fault that is located in the Los Angeles Basin in California. The thrust fault was discovered in 1999 and runs about 40 km (25 mi) in three discrete sections from the Puente Hills region in the southeast to just south of Griffith Park in the northwest. The fault is known as a blind thrust fault, as the fault plane does not extend to the surface. Large earthquakes on the fault are relatively infrequent but computer modeling has indicated that a major event could have substantial impact in the Los Angeles area. The fault is now thought to be responsible for one moderate earthquake in 1987 and another light event that took place in 2010, with the former causing considerable damage and deaths.

The 1986 Chalfant Valley earthquake struck southern Mono County near Bishop and Chalfant, California at 07:42:28 Pacific Daylight Time on July 21. With a moment magnitude of 6.2 and a maximum Mercalli intensity of VI (Strong), the shock injured two people and caused property damage estimated at $2.7 million in the affected areas. There was a significant foreshock and aftershock sequence that included a few moderate events, and was the last in a series of three earthquakes that affected southern California and the northern Owens Valley in July 1986.

The 1940 El Centro earthquake occurred at 21:35 Pacific Standard Time on May 18 in the Imperial Valley in southeastern Southern California near the international border of the United States and Mexico. It had a moment magnitude of 6.9 and a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. It was the first major earthquake to be recorded by a strong-motion seismograph located next to a fault rupture. The earthquake was characterized as a typical moderate-sized destructive event with a complex energy release signature. It was the strongest recorded earthquake to hit the Imperial Valley, and caused widespread damage to irrigation systems and led to the deaths of nine people.

<span class="mw-page-title-main">American Canyon High School</span> Public, coeducational school in American Canyon, California, United States

American Canyon High School is a public comprehensive high school located in American Canyon, California. It is operated by the Napa Valley Unified School District.

The 1979 Imperial Valley earthquake occurred at 16:16 Pacific Daylight Time on 15 October just south of the Mexico–United States border. It affected Imperial Valley in Southern California and Mexicali Valley in northern Baja California. The earthquake had a relatively shallow hypocenter and caused property damage in the United States estimated at US$30 million. The irrigation systems in the Imperial Valley were badly affected, but no deaths occurred. It was the largest earthquake to occur in the contiguous United States since the 1971 San Fernando earthquake eight years earlier.

<span class="mw-page-title-main">First Presbyterian Church (Napa, California)</span> Historic church in California, United States

First Presbyterian Church is a historic church at 1333 3rd Street in Napa, California.

<span class="mw-page-title-main">Goodman Library</span> United States historic place

The Goodman Library is a historic library located at 1219 1st St. in Napa, California. Built in 1901, the library was paid for by George E. Goodman and built on land donated by Goodman. Architect Luther M. Turton designed the building in the Richardson Romanesque style, which can be seen in its use of rusticated stone, round arch windows, and massive scale. The design represented a shift in Napa architecture, which was mainly Victorian prior to the library's construction.

<span class="mw-page-title-main">United States Post Office (Napa, California)</span> United States historic place

The U.S. Post Office, also known as the Napa Franklin Station, served the 94559 zip code area of Napa, California. The post office was built in 1933 with funding from the Public Works Administration. Architect William H. Corlett designed the Art Deco building. The front facade of the building has three sections; the central section has six bays divided by piers with terra cotta capitals. A terra cotta cornice adorned with ram and cow heads tops the central section. The side sections, which contain the building's two entrances, feature panels with decorative eagle designs above the doorways and urn-shaped bronze light fixtures on either side. The post office's lobby features a painted bas-relief plastic ceiling, unusual in federally constructed post offices, and a terrazzo floor.

<span class="mw-page-title-main">West Napa Fault</span>

The West Napa Fault is a 57 km (35 mi) long geologic fault in Napa County, in the North Bay region of the San Francisco Bay Area in northern California. It is believed to be the northern extension of the Calaveras Fault in the East Bay region.

The Berkeley Seismological Laboratory (BSL) is a research lab at the Department of Geology at the University of California, Berkeley. It was created from the Berkeley Seismographic Stations, a site on the Berkeley campus where Worldwide Standard Seismographic Network instruments were first deployed in 1959. Today, BSL's mission is to "support fundamental research into all aspects of earthquakes, solid earth processes, and their effects on society".

The 2000 Yountville earthquake occurred with a moment magnitude of 5 on a previously unmapped fault, about 3 miles (4.8 km) south southwest of Yountville, California in the Mayacamas Mountain Range under Mount Veeder and about 9 miles (14 km) south northwest of Napa, California. It occurred at 01:36 PDT on September 3.

<span class="mw-page-title-main">Napa County Courthouse Plaza</span> United States historic place

The Napa County Courthouse Plaza is a complex in Napa, California, which consists of the Napa County Courthouse and the Hall of Records. The two buildings occupy an entire city block, which includes open areas and landscaping to create the site's plaza setting. The High Victorian Italianate courthouse was built in 1878 to replace the original 1856 courthouse. The courthouse continues to serve as the seat of Napa County government. The 1916 Hall of Records is a federally sponsored records building designed by William H. Corlett. The Renaissance Revival building represents an early use of reinforced concrete as a building material; the material became popular nationwide in the 1920s.

The Uptown Theatre is an entertainment venue located in Napa, California, United States. The theater is in an Art Deco style building that originally opened to the public in 1937. As of 2023 it is utilized as a concert and entertainment venue with a seating capacity of 863.

<span class="mw-page-title-main">ShakeAlert</span> Earthquake early warning system for the west coast of the United States

ShakeAlert is an earthquake early warning system (EEW) in the United States, developed and operated by the United States Geological Survey (USGS) and its partners. As of 2021, the system issues alerts for the country's West Coast. It is expected that the system will be expanded to other seismically active areas of the United States in the future.

The 2019 Ridgecrest earthquakes of July 4 and 5 occurred north and northeast of the town of Ridgecrest, California located in Kern County and west of Searles Valley. They included three initial main shocks of Mw magnitudes 6.4, 5.4, and 7.1, and many perceptible aftershocks, mainly within the area of the Naval Air Weapons Station China Lake. Eleven months later, a Mw  5.5 aftershock took place to the east of Ridgecrest. The first main shock occurred on Thursday, July 4 at 10:33 a.m. PDT, approximately 18 km (11.2 mi) ENE of Ridgecrest, and 13 km (8.1 mi) WSW of Trona, on a previously unnoticed NE-SW trending fault where it intersects the NW-SE trending Little Lake Fault Zone. This quake was preceded by several smaller earthquakes, and was followed by more than 1,400 detected aftershocks. The M 5.4 and M 7.1 quakes struck on Friday, July 5 at 4:08 a.m. and 8:19 p.m. PDT approximately 10 km (6 miles) to the northwest. The latter, now considered the mainshock, was the most powerful earthquake to occur in the state in 20 years. Subsequent aftershocks extended approximately 50 km (~30 miles) along the Little Lake Fault Zone.

The 1987 Superstition Hills and Elmore Ranch earthquakes were a pair of earthquakes measuring Mw  6.0 and 6.5 that rattled the Imperial Valley of California. The earthquakes caused damage in Southern California and Mexico, but was limited due to their location in a sparsely populated area. It was felt as far as Las Vegas and Phoenix. More than 90 were injured, and two people were killed in Mexico.

References

  1. 1 2 3 4 5 6 USGS. "M6.0 – 6km NW of American Canyon, California". United States Geological Survey.
  2. 1 2 Carter, Lori (August 28, 2014). "Napa quake damage rises to $362 million". The Press Democrat . Santa Rosa. Retrieved August 28, 2014.
  3. 1 2 Stevens, Matt. Napa, Calif., earthquake: Economic hit could reach $1 billion, Los Angeles Times , August 25, 2014.
  4. ↑ Brocher, T. M.; Baltay, A. S.; Hardebeck, J. L.; Pollitz, F. F.; Murray, J. R.; Llenos, A. L.; Schwartz, D. P.; Blair, J. L.; Ponti, D. J.; Lienkaemper, J. J.; Langenheim, V. E.; Dawson, T. E.; Hudnut, K. W.; Shelly, D. R.; Dreger, D. S.; Boatwright, J.; Aagaard, B. T.; Wald, D. J.; Allen, R. M.; Barnhart, W. D.; Knudsen, K. L.; Brooks, B. A.; Scharer, K. M. (2015). "The Mw 6.0 24 August 2014 South Napa Earthquake". Seismological Research Letters. 86 (2A): 309–326. doi:10.1785/0220150004.
  5. ↑ Levs, Josh (September 11, 2014), Powerful California earthquake now blamed for one death, CNN
  6. 1 2 3 Moore, Derek; Rossmann, Randi (August 14, 2014). "Napa's people, buildings hit hard by 6.0 earthquake". The Press Democrat . Santa Rosa. Retrieved August 25, 2014.
  7. ↑ Fimrite, Peter (August 27, 2014). "Boats, grapes and Poseidon at Napa quake's epicenter". San Francisco Chronicle . Retrieved September 2, 2017.
  8. ↑ Brocher, T. M.; Baltay, A. S.; Hardebeck, J. L.; Pollitz, F. F.; Murray, J. R.; Llenos, A. L.; Schwartz, D. P.; Blair, J. L.; Ponti, D. J.; Lienkaemper, J. J.; Langenheim, V. E.; Dawson, T. E.; Hudnut, K. W.; Shelly, D. R.; Dreger, D. S.; Boatright, J.; Aagaard, B. T; Wald, D. J.; Allen, R. M.; Barnhart, W. D.; Knudsen, K. L.; Brooks, B. A.; Scharer, K. M. (2015), "The Mw 6.0 24 August 2014 South Napa Earthquake" (PDF), Seismological Research Letters, 86 (2A): 309, doi:10.1785/0220150004
  9. ↑ Yeats, R. (2012), Active Faults of the World, Cambridge University Press, pp. 82, 83, ISBN   978-0521190855
  10. 1 2 3 4 Josh Levs; Susanna Capelouto & Joshua Berlinger (August 24, 2014). "Northern California earthquake is area's strongest in 25 years". CNN. Retrieved August 25, 2014.
  11. 1 2 Lee Romney; Ryan Parker; Christine Mai-Duc; Lauren Raab (August 24, 2014). "After earthquake near Napa, up to 100 homes labeled unfit to enter". Los Angeles Times . Retrieved August 25, 2014.
  12. ↑ Rossmann, Randi (August 26, 2014). "3.9M aftershock rattles Napa". The Press Democrat . Santa Rosa. Archived from the original on September 3, 2014. Retrieved August 27, 2014.
  13. ↑ "Strong Earthquake Shakes Northern California". The Wall Street Journal . August 24, 2014. Retrieved August 24, 2014.
  14. ↑ Williams, Kate (September 15, 2014). "Napa quake: Obama declares major disaster, freeing up aid". San Francisco Chronicle . Retrieved September 2, 2017.
  15. ↑ Yune, Howard (March 20, 2018). "Earthquake damage repaired, Napa's Native Sons building shines again". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved March 21, 2018.
  16. ↑ Huffman, Jennifer (September 11, 2014). "Uptown to remain closed until November". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 11, 2014.
  17. ↑ Huffman, Jennifer (August 25, 2014). "Damaged businesses struggle to reopen". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved August 26, 2014.
  18. ↑ Wetzstein, Janelle (August 24, 2014). "Shattered property, bruised lives". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved August 26, 2014.
  19. 1 2 Fimrite, Peter. Northern California earthquake: Blue-collar Vallejo hit hard, San Francisco Chronicle , August 26, 2014.
  20. ↑ Polson, Burt (September 1, 2014). "A red-tagged building and a tenant". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 11, 2014.
  21. ↑ Cabanatuan, Michael (August 24, 2014). "Earthquake cracks, buckles roads, but leaves bridges OK". SF Gate . Napa, CA. Retrieved August 26, 2014.
  22. ↑ Paulsen, Sasha (August 25, 2014). "Wine industry tallies spilled wine, shattered barrels". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved August 25, 2014.
  23. ↑ Jensen, Peter (September 9, 2014). "Napa quakes causes $80 million blow to wine industry, report says". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 11, 2014.
  24. ↑ Ynue, Howard (September 17, 2014). "Napa tallies earthquake damage across city". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 18, 2014.
  25. ↑ KGO-TV report from Queen of the Valley Medical Center, 4:45 pm
  26. ↑ Rong-Gong Lin II (September 10, 2014). "Napa earthquake death: 2 weeks later, quake claims first victim -". LA Times. Retrieved September 10, 2014.
  27. ↑ Todorov, Kerana (September 9, 2014). "First earthquake-related death reported". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 11, 2014.
  28. ↑ Yune, Howard (November 17, 2014). "Crumbled by Napa earthquake, Uptown Theatre mural rises again". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved November 17, 2014.
  29. ↑ Huffman, Jennifer (July 9, 2016). "First Presbyterian church returns to quake-damaged sanctuary after almost two years". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  30. ↑ Huffman, Jennifer (August 23, 2015). "Churches repair and reopen after quake". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  31. ↑ Yune, Howard (November 17, 2015). "After earthquake repairs, Napa Methodist church to reopen Sunday". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  32. ↑ Yune, Howard (January 25, 2017). "Napa awards repair contract for quake-damaged Goodman Library". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  33. ↑ Huffman, Jennifer (March 10, 2017). "Napa's old post office sold for $2 million for a hotel". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  34. ↑ Eberling, Barry (September 1, 2017). "Repair of earthquake damage to Napa courthouse to start soon". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved September 2, 2017.
  35. ↑ Lander, Jess (March 30, 2017). "Trefethen rebounds after the earthquake". Napa Valley Register . Napa, CA: Lee Enterprises, Inc. Retrieved April 9, 2017.
  36. ↑ Kovner, Guy (September 4, 2014). "Napa quake jumpstarts stream flows, though probably only temporarily". The Press Democrat . Retrieved September 4, 2014.
  37. ↑ Fimrite, Peter (September 6, 2014). "Surprise bonanza since Napa quake: dry creeks now flowing". San Francisco Chronicle. Retrieved September 7, 2014.
  38. ↑ "Experimental warning system gave 10-second alert before California earthquake". CBS News . August 24, 2014. Archived from the original on August 25, 2014.
  39. ↑ Block, Melissa. "In Latest Calif. Earthquake, Shake Alert Tests Its Legs". NPR.org. Retrieved August 23, 2015.
  40. ↑ Allen, Richard M.; Given, Douglas D.; Heaton, Thomas H.; Vidale, John E. (2014). "Successful ShakeAlert Performance for the Napa Quake". 2014 AGU Fall Meeting. 44 (S44D–01): S44D–01. Bibcode:2014AGUFM.S44D..01A.
  41. ↑ Wurman, Gilead; Price, Michael J. (2014). "Earthquake Warning Performance in Vallejo for the South Napa Quake". 2014 AGU Fall Meeting. San Francisco, CA (S33F–4937).
  42. ↑ Elinson, Zusha (August 25, 2014). "Expanding Earthquake Warning System May Help the Public". Wall Street Journal. Retrieved August 26, 2014.
  43. ↑ Rong-Gong Lin II (December 14, 2014). "California receives U.S. funding for earthquake early-warning system- LA Times" . Retrieved December 31, 2014.

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.