Franciscan Complex rocks

E238972

Franciscan Complex rocks are a chaotic assemblage of metamorphosed oceanic crust, sediments, and volcanic rocks formed in an ancient subduction zone along the western margin of North America.

All labels observed (1)

Label Occurrences
Franciscan Complex rocks canonical 1

How this entity was disambiguated

Statements (47)

Predicate Object
instanceOf accretionary complex
geologic formation
mélange
subduction complex
ageRange Late Jurassic to Miocene
associatedWith Farallon Plate
North American Plate
containsFossils deep‑marine radiolaria
marine macrofossils (locally)
containsRockType basalt
blueschist
chert
eclogite
greenstone
greywacke sandstone
limestone
metagraywacke
serpentinite
shale
deformationProcesses block‑in‑matrix fabric formation
shearing
subduction‑related underplating
exposedIn Central California Coast Ranges
Northern California Coast Ranges
San Francisco Bay Area
formedFrom deep‑marine sediments
oceanic crust
volcanic rocks
locatedIn California, United States
surface form: California
locatedOn western margin of North America
metamorphicFacies blueschist facies
eclogite facies
greenschist facies
metamorphicGrade high‑pressure low‑temperature
namedAfter Spanish Franciscans
surface form: Franciscan friars of Mission San Francisco de Asís
oldestAge Late Jurassic
overlies Coast Range Ophiolite
partOf Coastal Ranges
surface form: California Coast Ranges
significance record of Mesozoic–Cenozoic subduction along western North America
structuralStyle chaotic mélange
imbricate thrust sheets
tectonicSetting convergent plate margin
subduction zone
underlies Great Valley Group
usedFor studies of accretionary prism processes
studies of high‑pressure metamorphism
youngestAge Miocene

How these facts were elicited

Referenced by (1)

Full triples — surface form annotated when it differs from this entity's canonical label.

Santa Cruz Mountains geology Franciscan Complex rocks