The Marichuela Formation (, N1m) is a geological formation of the Bogotá savanna, Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consists of coarse to very coarse conglomerates. The Marichuela Formation dates to the Neogene period; Late Miocene to Early Pliocene epochs, and has a maximum thickness of .
Etymology The formation was defined by Helmens and Van der Hammen in 1995 and named after the Marichuela neighbourhood of Usme.Montoya & Reyes, 2005, p.65 Part of the Marichuela Formation had been included in the Conos de Tunjuelo, defined by Julivert in 1961.Suna Hisca, s.a., p.45
Description Lithologies The Marichuela Formation consists of coarse to very coarse conglomerates.
Stratigraphy and depositional environment The Marichuela Formation unconformably overlies the Cretaceous rocks of the Guadalupe Group. The age has been estimated to be Late Miocene to Early Pliocene.Montoya & Reyes, 2005, p.67 The depositional environment has been interpreted as alluvial fans, caused by earthquakes or heavy rains.Montoya & Reyes, 2005, p.66
Outcrops
The Marichuela Formation is apart from its type locality in the Usme Synclinal, the valley of the Tunjuelo River, found in the synclinals of Neusa, Sisga and La Calera.
Regional correlations
See also
Geology of the Eastern Hills Geology of the Ocetá Páramo Geology of the Altiplano Cundiboyacense
Notes
References
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