Noreán Formation
The Noreán Formation (, J1-2n, J1n) is a geological formation of the Eastern Ranges of the Colombian Andes, the Serranía de San Lucas and as basement underlying the southernmost Lower and northern Middle Magdalena Valleys. The formation consists of volcanic and pyroclastic lavas that range from andesites to rhyolites. Vitric, lithic and crystal tuffs and andesitic dikes and hypabyssal bodies are also present in the formation.

The more than thick formation was deposited in a continental arc magmatic setting in an Early Jurassic graben that presently forms the basement of the Middle Magdalena Valley (VMM). A positive anomaly of Pb suggests a subduction-related genesis dominated by explosive volcanism.
Q736917
geological formation
Concept
Q143014
Eastern Ranges
LOC
Q739
Colombia
LOC
Q5456
Andes
LOC
Q3479950
Serranía de San Lucas
LOC
Q2143968
basement
Concept
None
Lower
UNK
Q20658375
Middle Magdalena Valley
LOC
Q108689
volcanic
Concept
Q512121
pyroclastic
Concept
Q40157
lava
Concept
Q181908
andesite
Concept
Q190727
rhyolite
Concept
Q484924
tuff
Concept
Q662806
dikes
Concept
Q2323389
hypabyssal
Concept
Q192810
graben
Concept
Q708
Pb
Concept
Q176318
subduction
Concept
Q97327475
Noreán Formation
UNK
+1^^http://www.w3.org/2001/XMLSchema#decimal
1
NUMBER
-2^^http://www.w3.org/2001/XMLSchema#decimal
-2
NUMBER
+1^^http://www.w3.org/2001/XMLSchema#decimal
1
NUMBER
country
mountain range
country
country
country
subclass of