Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Magdalena Valley


Occurrence number: 
Longitude: -75.9142, Latitude: 1.7906

The Magdalena Valley of the Huila Department, Colombia is host to volcanic province, found to the east of the Cordillera Central of the Colombian Andes. The province consists of vents and flows composed of a range of alkaline, basic to ultrabasic lithologies. Occurrences are found across four areas: San Agustín – San José de Isnos, La Argentina, Ororapa – San Roque, and Acevedo. Alkali olivine basalts, mela-tephriphonolites, and nepheline basanites are the main components of the San Agustín, San José de Isnos, and Ororapa – San Roque areas, with the latter two rock types containing normative nepheline. In the Acevedo area, the main components are ultrabasic lavas corresponding to mafitic nephelinites, occasionally entraining peridotite nodules. Whole rock and trace element data and Rittmann Norms for the lithologies mentioned can be found in Kroonenberg et al. (1982).

31.2 ± 2.7 Ma, but authors suspect this may be anomalously high, more likely Pliocene-Pleistocene (Kroonenberg et al., 1982)

KROONENBERG, S.B., PITCHER, M. & DIEDERIX, H., 1982. Cenozoic alkalibasaltic to ultrabasic volcanism in the uppermost Magdalena Valley, Southern Huila Department, Colombia. Geologia Novandia 5 Mayo pp 19-26

Fig 1. Regional map including Magdelena Valley (Kroonenberg et al., 1982, Fig 1.)
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith