Llajas Formation

{{Short description|Geologic formation in Southern California, United States}}

{{Infobox rockunit

| name = Llajas Formation

| image = Turritella andersoni, Llajas Formation, Paleogene - Natural History Museum of Utah - DSC07417.JPG

| caption = Fossil from the Llajas Formation

| type = Geologic formation

| age = Eocene

| period = Eocene

| prilithology = Conglomerate

| otherlithology =

| namedfor =

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| region = California

| country = {{USA}}

| coordinates =

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| underlies = Sespe Formation

| overlies = Santa Susana Formation

| thickness =

| extent = Transverse Ranges,
Southern California

| area =

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The Llajas Formation is a non-marine to marine conglomerate geologic formation in Southern California.

It is found in the Transverse Ranges geologic province, within Los Angeles County and Ventura County. Locations include the Simi Hills, Simi Valley, and Santa Susana Mountains.[https://decapoda.nhm.org/pdfs/37041/37041-001.pdf CSUN: 'Geologic Profile of Simi Valley']; by Richard Squires, PhD; 1997.

;Fossils

It preserves fossils dating back to the early and middle Eocene epoch of the Paleogene period.{{cite web|title= Fossilworks: Gateway to the Paleobiology Database|author= ((Various Contributors to the Paleobiology Database))|url= https://www.fossilworks.org|access-date= 17 December 2021}}