1899 San Jacinto earthquake

Earthquake in Southern California May 2025 February 2025 1899 San Jacinto earthquake USA California California 33.8 -117.0 Bullseye1.png 40 yes 260 right 1899-12-25 12:25:00 yes cdmg18991225122500000 1899 12 25 04:25 30 seconds 6.7 w y 33.8 -117.0 region:US_type:event inline,title San Jacinto Fault Zone $50,000 9 Yes 6 dead, 8 injured The 1899 San Jacinto earthquake occurred on Christmas morning (December 25) at 04:25 local time in Southern California. The estimated moment magnitude 6.7 earthquake had an epicenter located 10 miles southeast of San Jacinto. The earthquake had a maximum Mercalli intensity of IX (Violent). Severe damage occurred, amounting to US$50,000 (1899 rate), as well as six fatalities.M 6.7 – Near San Jacinto, California https://earthquake.usgs.gov/earthquakes/eventpage/cdmg18991225122500000/executive United States Geological Survey 14 January 2022 Tectonic setting The mainshock occurred on a segment of the San Jacinto Fault Zone. This highly segmented, 210-km-long strike-slip fault that forms part of the boundary between the North American and Pacific plates. The fault is part of a complex plate boundary system known as the San Andreas Fault System. It runs parallel to the San Andreas Fault, west of the Salton Sea, and is separated from the San Andreas Fault by the San Jacinto Mountains to its east. It cuts under cities including Hemet, Colton, and San Bernardino along the way, before joining the San Andreas Fault at Devore. Because the fault is so segmented, some branches have their own names, although they are considered part of the system of faults. The San Jacinto Fault is thought to be the most active fault in California. It is the source of at least 11 earthquakes measuring w 6.0 or greater since the late 19th century. The most recent earthquakes were the doublet event of 1987. The 1987 pair of temblors inflicted heavy damage to Westmorland, and indirectly killed two people outside Mexicali. Another strong earthquake struck nearby in 1968.Singer Eugene Geology of California's Imperial Valley http://www.sci.sdsu.edu/salton/San%20AndreasFaultSyst.html#:~:text=The%20most%20seismically%20active%20fault,of%20the%20San%20Andreas%20system. 13 December 2020 sci.sdsu.edu Earthquake The 1899 earthquake occurred on a segment of the San Jacinto Fault that also ruptured in a similar-sized quake in 1918. A study on earthquakes on the San Jacinto Fault found that the earthquakes had lowered the coulomb stress on the southern segment of the San Andreas Fault, delaying the occurrence of a large rupture. The last San Andreas Fault rupture in the region was in 1680.Gang Luo Mian Liu Mechanical coupling between the San Jacinto fault and the San Andreas fault Lithosphere 2012 4 3 221–229 10.1130/L180.1 https://www.researchgate.net/publication/261698209 free The San Jacinto Valley segment is believed to be the source of the 1899 earthquake. The rupture is located within the valley area, possibly on the Casa Loma strand.LiDAR and Field Observations of Slip Distribution for the Most Recent Surface Ruptures along the Central San Jacinto Fault http://bssa.geoscienceworld.org/content/102/2/598.short J. B. Salisbury T. K. Rockwell T. J. Middleton K. W. Hudnut 2012 Bulletin of the Seismological Society of America Seismological Society of America 102 2 598–619 10.1785/0120110068 2012BuSSA.102..598S subscription Damage Lasting 30 seconds, damage was severe. Many, but not all brick buildings in the Hemet and San Jacinto were demolished.Stover C. W. Coffman J. L. Seismicity of the United States, 1568–1989 (Revised) U.S. Geological Survey Professional Paper 1527 https://books.google.com/books?id=bY0KAQAAIAAJ 1993 United States Government Printing Office Every brick building on Main Street was extensively damaged, littering the road with bricks. Two-storey buildings lost their second floors and power lines were down. The San Jacinto County Hospital was completely unrecognizable after many of its brick walls were torn off. Despite the extent of damage, the occupants were unharmed.Kim Jarrell Johnson BACK IN THE DAY: Christmas quake struck in 1899 https://www.pressenterprise.com/2013/12/12/back-in-the-day-christmas-quake-struck-in-1899/ 14 January 2022 The Press-Enterprise 12 December 2013 In Hemet, the quake knocked off all but two chimneys. The Hemet Hotel suffered extensive damage and a veranda on the west wall was completely torn. Many bricks fell from the building and it was eventually unsafe for use. Every high school in the city was damaged, delaying school reopenings after the Christmas holidays. Brick structures suffered partial collapses while wood-constructed buildings shifted off their foundations. A 150-foot-long fissure formed beneath a house, twisting and wrenching its wooden frame. This fissure is thought to be a surface rupture of the fault.Tousson R. Toppozada Charles R. Real Stephen P. Bezore David L. Parke Open-File Report 1981 Preparation of isoseismal maps and summaries of reported effects for pre-1900 California earthquakes United States Geological Survey 10.3133/ofr81262 81–262 free In Riverside, chimneys toppled and brick buildings suffered cracks. In the Soboba Indian Reservation, Riverside County, six elders of the Soboba Band of Luiseño Indians were killed. A further eight were seriously injured when an adobe wall fell.Significant Earthquake Information https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-more-info/2564 NOAA National Centers for Environmental Information 14 January 2022 At Murrieta, the quake destroyed an adobe home. Two-thirds of the city's homes were slightly damaged. Damage was also reported in the San Bernardino-Banning area. There was some minimal damage as far away as Los Angeles and San Diego. A major landslide occurred in the San Jacinto Mountains and a rockslide at Escondido. Increased flow of water at a spring was observed at Murrieta Hot Springs and Sage, and hot springs formed at Jacumba. The San Bernardino Transcript reported that large dust clouds formed on the San Jacinto Mountains. The forest patrol thought the clouds were from a fire but when they arrived, a large fissure six feet wide and was formed. See also List of earthquakes in California List of earthquakes in the United States References Category:December 1899 in the United States Category:1899 earthquakes Category:Earthquakes in California Category:1899 natural disasters in the United States Category:1899 in California Category:San Jacinto, California Category:Organized events in Riverside County, California