Resumo

MORTON-BERMEA, O.; AURORA ARMIENTA, M.  e  RAMOS, S.. Rare-earth element distribution in water from El Chichón Volcano Crater Lake, Chiapas Mexico. Geofís. Intl [online]. 2010, vol.49, n.1, pp.43-54. ISSN 2954-436X.

This research can be regarded as a pilot study at El Chichón Volcano to assess whether REE distributions can be used as routinely geochemical tracers in the Crater Lake geothermal system. Eighteen lake water samples were collected during 3 field campaigns (Group 1, Group 2, and Group 3) from March 2006 to May 2008 at the same sites around the lake. The chemical data has documented the temporal evolution of the hydrothermal system as changes in major element chemistry. However, these samples do not evidence significant variations in the REE geochemistry corresponding to the observed volcanic stability during this period. The concentrations of the REE ranged between 5.58 ppb (Ce) and 0.01 ppb (Lu). Lake water from El Chichón Volcano show HREE enriched patterns with respect to the 1982 pumice samples (as representative of the host rock). The small Eu anomaly observed in recent samples may be due to the increase of complexing agents such as soluble sulfates, chlorides and fluorides.

Palavras-chave : Rare earth elements; geochemistry; El Chichón Volcano; ICP-MS; Mexico.