Elsinore Valley is a

graben In geology, a graben () is a depressed block of the crust of a planet or moon, bordered by parallel normal faults. Etymology ''Graben'' is a loan word from German, meaning 'ditch' or 'trench'. The word was first used in the geologic contex ...

rift valley A rift valley is a linear shaped lowland between several highlands or mountain ranges created by the action of a geologic rift. Rifts are formed as a result of the pulling apart of the lithosphere due to extensional tectonics. The linear dep ...

in western

Riverside County, California Riverside County is a County (United States), county located in the southern California, southern portion of the U.S. state of California. As of the 2020 United States Census, 2020 census, the population was 2,418,185, making it the fourth-most ...

, a part of the

Elsinore Trough The Elsinore Trough is a graben rift valley in Riverside County, southern California. It is created by the Elsinore Fault Zone. It is located between the Santa Ana Mountains to the west, and the Temescal Mountains of the Perris Block and the T ...

. The Elsinore Valley is a graben between the Santa Ana Block to the southwest and the

Perris Block The Perris Block is the central block of three major Fault block, fault-bounded blocks of the northern part of the Peninsular Ranges. The Perris Block lies between the Santa Ana Block to the west and the San Jacinto Block to the east. The Perris B ...

on the northeast. It is a complex graben, divided lengthwise into several smaller sections by transverse faults. The Elsinore Valley graben is bounded northeast side by the Glen Ivy longitudinal fault on the north shore of

Lake Elsinore Lake Elsinore is a natural freshwater lake in Riverside County, California, located east of the Santa Ana Mountains and fed by the San Jacinto River. Originally named ''Laguna Grande'' by Spanish explorers, it was renamed for the town of Elsino ...

at the foot of the Clevelin Hills and similarly on the southeast by the

Willard Fault Willard may refer to: People * Willard (name) Geography Places in the United States * Willard, Colorado * Willard, Georgia * Willard, Kansas * Willard, Kentucky * Willard, Michigan, a small unincorporated community in Beaver Township, Bay ...

that runs along the at the foot of the

Santa Ana Mountains The Santa Ana Mountains are a short peninsular mountain range along the coast of Southern California in the United States. They extend for approximately southeast of the Los Angeles Basin largely along the border between Orange and Riverside co ...

and parallel to the Elsinore Fault along the southwest shore of Lake Elsinore to

Rome Hill Rome Hill, also called St. Davids Hill, is a small summit at the southeast corner of Lake Elsinore Lake Elsinore is a natural freshwater lake in Riverside County, California, located east of the Santa Ana Mountains and fed by the San Jacinto Ri ...

and the Willard Fault continues on as the west side of the

Temecula Valley The Temecula Valley is a graben rift valley in western Riverside County, California. The Temecula Valley is one of the graben valleys making up the Elsinore Trough, created by the Elsinore Fault Zone. It lies between the Wildomar Fault on the e ...

graben and

Wolf Valley Wolf Valley is a graben rift valley in the Elsinore Trough, in western Riverside County, California. Overview Wolf Valley is the southernmost of the graben valleys making up the Elsinore Trough, created by the Elsinore Fault Zone. It lies betw ...

graben. At the south end of Lake Elsinore the

Wildomar Fault Wildomar is a city in southwest Riverside County, California, United States. The city was incorporated on July 1, 2008. As of the 2020 census, the population was 36,875. The community has grown very quickly during the early twenty-first century; t ...

enters the lake just east of Rome Hill, running southeast on the northwest side of the

. The Elsinore Valley is marked in the south by the rise between the Elsinore and Temecula Valley. In the north the valley bounds are marked by the Santa Ana Mountain ridges moved eastward along the

Los Pinos Los Pinos (English: ''The Pines'') was the official residence and office of the President of Mexico from 1934 to 2018. Located in the Bosque de Chapultepec (Chapultepec Forest) in central Mexico City, it became the presidential seat in 1934, wh ...

and

Lucerne Lucerne ( , ; High Alemannic German, High Alemannic: ''Lozärn'') or Luzern ()Other languages: gsw, Lozärn, label=Lucerne German; it, Lucerna ; rm, Lucerna . is a city in central Switzerland, in the Languages of Switzerland, German-speaking po ...

transverse faults, dividing the Elsinore Valley from the Temescal Valley graben. Rene Engal, Geologic Map of Lake Elsinore Quadrangle, State of California, Department of Natural Resources, 1959
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References

Valleys of Riverside County, California Inland Empire Valleys of California {{RiversideCountyCA-geo-stub