Jaroso Hydrothermal System

J. Martinez-Frias, R. Lunar, Fernando Rull, J.A. Rodriguez-Losada, A. Delgado & R. Frost

The SE Mediterranean margin of Spain is an area of synchronous interaction of tectonic, volcanic, evaporitic and mineralizing hydrothermal processes. The Jaroso Hydrothermal System (JHS) is an extremely interesting late-volcanic episode, and the Jaroso Ravine, located in Sierra Almagrera (Cuevas del Almanzora area, Almeria province, SE Spain), is the best outcrop  where the mineralization (Jaroso vein) and alteration, have attained the maximum surface expression. Jarosite was first characterized as a new mineral on Earth in Spain in 1852 in the Jaroso Ravine, which is the world type locality.

We suggest that the multistage hydrothermal system of El Jaroso (Jaroso Hydrothermal System), which is responsible for both the Jaroso ores (especially rich in jarosite) and the Las Herrerias sulfate-rich, shallow-marine laminites, could be exploited as a potential model with important implications for the exploration of Mars.

First Raman spectra of natural jarosites from El Jaroso and RioTinto areas:

Rull, F., Martinez-Frias, J., Medina, J. & Gonzalez-Pastor, E. (2004) A comparative analysis of mineral sulphates from Rio Tinto and Jaroso Ravin (Spain) using XRD,  FTIR and Raman Spectroscopy (June 8th 2004 GeoRaman 2004 - Hawaii, USA)

General view of The Jaroso Ravine

(Sierra Almagrera, Almeria province, Spain) around 1880
Photo: Courtesy of Junta de Andaluca

General view of El Jaroso Ravine (Sierra Almagrera, Almeria province, Spain)

Photo: Web Los Lobos. Oasis de Almeria. Autor: Blas Guevara Martinez

Lpez Gutirrez, J., Martnez-Fras, J. & Lunar, R. (1993) "Relationships between tectonics and base- and precious-metal mineralization in the Vera-Garrucha area (SE Spain)" En: Fenoll, P., Torres Ruiz, J. & Gervilla, F. (Eds) Current Research in Geology Applied to Ore deposits, Society of Geology Applied to Mineral Deposits, I:735-739.

Alteration crust rich in jarosite and other sulfates at El Jaroso Ravine, Sierra Almagrera (SE Spain)

Gypsum layers in the exhalites of the Las Herrerias mineralization (Jaroso Hydrothermal System)

Jarosite samples

Alteration crust rich in jarosite

JHS sulfates and association of halotrichite and jarosite (Frost et al. (2007)

Shallow-marine, low temperature hydrothermal chimneys

General overview of a part of the Jaroso Ravine, Sierra Almagrera, Almeria, Spain