1968 Borrego Mountain earthquake
E304975
The 1968 Borrego Mountain earthquake was a powerful magnitude 6.5–6.8 temblor in Southern California that caused significant surface rupture and damage, and became an important case study in modern seismology and fault mechanics.
All labels observed (1)
| Label | Occurrences |
|---|---|
| 1968 Borrego Mountain earthquake canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T2855560 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: 1968 Borrego Mountain earthquake Context triple: [San Jacinto Fault Zone, notableEarthquake, 1968 Borrego Mountain earthquake]
-
A.
Loma Prieta
Loma Prieta is a prominent peak in California’s Santa Cruz Mountains, best known for lending its name to the devastating 1989 Loma Prieta earthquake.
-
B.
1989 Loma Prieta earthquake
The 1989 Loma Prieta earthquake was a powerful magnitude 6.9 quake in Northern California that caused widespread damage in the San Francisco Bay Area, including freeway collapses and the disruption of the World Series.
-
C.
1992 Cape Mendocino earthquakes
The 1992 Cape Mendocino earthquakes were a sequence of powerful offshore quakes near Northern California that caused significant shaking, damage, and a small tsunami along the Pacific coast.
-
D.
1185 Lincoln earthquake
The 1185 Lincoln earthquake was a significant medieval seismic event in England that caused extensive damage in the city of Lincoln and led to major reconstruction of Lincoln Cathedral.
-
E.
1906 San Francisco earthquake
The 1906 San Francisco earthquake was a devastating magnitude 7.8 seismic event that struck Northern California, causing widespread destruction and fires that nearly leveled San Francisco and became one of the worst natural disasters in U.S. history.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: 1968 Borrego Mountain earthquake Target entity description: The 1968 Borrego Mountain earthquake was a powerful magnitude 6.5–6.8 temblor in Southern California that caused significant surface rupture and damage, and became an important case study in modern seismology and fault mechanics.
-
A.
Loma Prieta
Loma Prieta is a prominent peak in California’s Santa Cruz Mountains, best known for lending its name to the devastating 1989 Loma Prieta earthquake.
-
B.
1989 Loma Prieta earthquake
The 1989 Loma Prieta earthquake was a powerful magnitude 6.9 quake in Northern California that caused widespread damage in the San Francisco Bay Area, including freeway collapses and the disruption of the World Series.
-
C.
1992 Cape Mendocino earthquakes
The 1992 Cape Mendocino earthquakes were a sequence of powerful offshore quakes near Northern California that caused significant shaking, damage, and a small tsunami along the Pacific coast.
-
D.
1185 Lincoln earthquake
The 1185 Lincoln earthquake was a significant medieval seismic event in England that caused extensive damage in the city of Lincoln and led to major reconstruction of Lincoln Cathedral.
-
E.
1906 San Francisco earthquake
The 1906 San Francisco earthquake was a devastating magnitude 7.8 seismic event that struck Northern California, causing widespread destruction and fires that nearly leveled San Francisco and became one of the worst natural disasters in U.S. history.
- F. None of above. chosen
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
earthquake
ⓘ
natural disaster ⓘ |
| aftershocks | numerous ⓘ |
| casualties | 1 fatality ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| damage |
ground cracking
ⓘ
landslides ⓘ road and highway damage ⓘ structural damage in Southern California ⓘ |
| date | 1968-04-09 ⓘ |
| depth | about 10 km ⓘ |
| economicLosses | millions of US dollars ⓘ |
| epicenterNear | Borrego Mountain ⓘ |
| epicenterRegion |
Colorado Desert
ⓘ
surface form:
Anza-Borrego Desert
|
| epicenterState |
California, United States
ⓘ
surface form:
California
|
| fault | Coyote Creek Fault ⓘ |
| faultSystem | San Jacinto Fault Zone ⓘ |
| injuries | several injuries ⓘ |
| intensityScale | Modified Mercalli intensity scale ⓘ |
| localTime | 18:28 PST ⓘ |
| locatedIn |
Anza-Borrego Desert State Park
ⓘ
surface form:
Borrego Mountain area
San Diego County ⓘ Southern California ⓘ |
| magnitude |
6.5
ⓘ
6.6 ⓘ 6.8 ⓘ |
| magnitudeType |
Ms
ⓘ
Mw ⓘ |
| maximumIntensity | VIII ⓘ |
| maximumSurfaceDisplacement | about 2.5 meters ⓘ |
| observedPhenomenon |
aftershock sequence
ⓘ
ground rupture ⓘ |
| partOf |
California seismicity
ⓘ
history of earthquakes in California ⓘ |
| plateBoundary |
Pacific–North American plate boundary system
ⓘ
surface form:
Pacific Plate–North American Plate boundary
|
| recordedBy | United States Geological Survey ⓘ |
| regionAffected |
Imperial County
ⓘ
Southern California ⓘ
surface form:
Inland Southern California
San Diego County ⓘ |
| ruptureLength | approximately 30 km ⓘ |
| scientificSignificance |
important case study in fault mechanics
ⓘ
important case study in modern seismology ⓘ |
| slipType | right-lateral strike-slip ⓘ |
| surfaceRupture | yes ⓘ |
| tectonicSetting | transform plate boundary ⓘ |
| time | 02:28:15 UTC ⓘ |
| usedFor |
calibration of seismic hazard models in Southern California
ⓘ
studies of earthquake rupture dynamics ⓘ studies of surface faulting ⓘ |
| year | 1968 ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: 1968 Borrego Mountain earthquake Description of subject: The 1968 Borrego Mountain earthquake was a powerful magnitude 6.5–6.8 temblor in Southern California that caused significant surface rupture and damage, and became an important case study in modern seismology and fault mechanics.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.