Abstract
At Rodalquilar gold mineralization is found in Late Tertiary volcanic rocks of the Sierra del Cabo de Gata and is related to a caldera collapse. Radial and concentric faults were preferred sites for gold deposition. Hydrothermal activity produced a specific alteration zoning around gold-bearing vein structures, grading from an innermost advanced argillic via an argillic into a more regionally developed propylitic zone. Advanced argillic alteration with silica, pyrophyllite, alunite, and kaolinite extends down to several hundred m indicating a hypogene origin. High-grade gold mineralization in vein structures is confined to the near-surface part of the advanced argillic alteration. Fine-grained gold is associated with hematite, jarosite, limonite, or silica. At a depth of about 120 m, the oxidic ore assemblage grades into sulfide mineralization with pyrite and minor chalcopyrite, covellite, bornite, enargite, and tennantite. Two types of fluids from different sources were involved in the hydrothermal system. Overpressured and hypersaline fluids of presumably magmatic origin initiated the hydrothermal system. Subsequent hydrothermal processes were characterized by the influx of low-salinity solutions of probable marine origin and by interactions between both fluids. Deep-reaching, advanced argillic alteration formed from high-salinity fluids with 20–30 equiv. wt% NaCl at about 225°C. Near-surface gold precipitation and silification are related to fluids with temperatures of about 175°C and 3–4 equiv. wt% NaCl. Gold was transported as Au(HS) −2 , and precipitation resulted from boiling with a concomitant decrease in temperature, pressure, and pH and an increase in fO2. All features of the Rodalquilar gold deposit reveal a close relationship to acid-sulfate-type epithermal gold mineralization.
Similar content being viewed by others
References
Arribas, A. Jr., Rytuba, J.J., Cunningham, C.G., Kelly, W.C., Rye, R.O., Castroviejo, R.: Rodalquilar deposits, Spain, first example of caldera-related epithermal gold mineralization in Europe; part 2, ore genesis. In: GSA Annual Meeting, Geol. Soc. of Am., 1988 Centennial Meeting, A351 (1988)
Ballantyne, J.M., Moore, J.N.: Arsenic geochemistry in geothermal systems. Geochim. Cosmochim. Acta 52:475–483 (1988)
Bellon, H., Bordet, P., Montenat, C.: Chronologie du magmatisme neogene des Cordilleres betiques (Espagne meridionale). Bull. Soc. geol. France (7) XXV:205–207 (1983)
Bordet, P.: Le volcanisme miocene des Sierras de Gata et de Carboneras (Espagne du Sud-est). Doc. et Trav. IGAL, Paris, 8:70 pp (1985)
Eimon, P.I.: Epithermal models. In: Gold Update '87–'88: Epithermal gold. Course manual, University of Southampton, March 1988, 17–47 (1988)
Fournier, R.O.: The behavior of silica in hydrothermal solutions. In: Berger, BR, Bethke, P.M. (Eds.), Geology and Geochemistry of Epithermal Systems: Society of Economic Geologists. Reviews in Economic Geology 2:45–59 (1985)
Friedrich, G.: Petrographische und erzmikroskopische Beobachtungen an der Goldlagerstätte Rodalquilar, Prov. Almeria/Spanien. N. Jb. Mineral. Abh. 94:208–227 (1960)
Friedrich, G., Kross, G., Wiechowski, A.: Goldmineralisation in Rodalquilar, Spanien. Geol. Jb. A 75:345–359 (1984)
Haas J.L. Jr.: The effect of salinity on the maximum thermal gradient of a hydrothermal system at hydrostatic pressure. Econ. Geol. 66:940–946 (1971)
Hayba, D.O., Bethke, P.M., Heald, P., Foley, N.K.: Geologic, mineralogic, and geochemical characteristics of volcanic hosted epithermal precious-metal deposits. In: Berger, B.R., Bethke, P.M. (Eds.), Geology and Geochemistry of Epithermal Systems; Society of Economic Geologists. Reviews in Economic Geology 2:129–167 (1985)
Heald, P., Foley, N.K., Hayba, D.O.: Comparative anatomy of volcanic-hosted epithermal deposits: Acide-sulfate and adularia-sericite types. Econ. Geol. 82:1–26 (1987)
Hedenquist, J.W., Henley, R.W.: Hydrothermal eruptions in the Waiotapu Geothermal System, New Zealand: Their origin, associated breccias, and reletion to precious metal mineralization. Econ. Geol. 80:1640–1668 (1985)
Hedenquist, J.W, Matsuhisa, Y., Izawa, E., Marumo, K., Aoki, M., Sasaki, A.: Epithermal gold mineralization of acid-leached rocks in the Nansatsu District of Southern Kyushu, Japan. In: Bicentennial Gold 88: Extended abstracts oral programme; Geological Society of Australia Inc. 22:183–190 (1988)
Henley, R.W.: The geothermal framework for epithermal deposits. In: Berger, B.R., Bethke, P.M. (Eds.), Geology and Geochemistry of Epithermal systems; Society of Economic Geologists. Reviews in Economic Geology 2:1–24 (1985)
Henley, R.W., Berger, B.R.: Advances in the understanding of epithermal precious-metal deposits. In: Bicentennial Gold 88: Extended abstracts oral programme. Geological Society of Australia 22:277–283 (1988)
Hollister, L.S., Crawford, M.L.: Short Course in fluid inclusions: Applications to petrology. Mineralogical Association of Canada, 304 pp (1981)
Hollister, V.F. Ed.: Discoveries of epithermal precious metal deposits. AIME, New York, 169 pp (1985)
Kisters, A.: Die goldvererzten Gangstrukturen Maria Josefa und Triunfo, Rodalquilar/SE-Spanien: Geologisch-mineralogischgeochemische Untersuchungen. Diploma thesis (unpubl.), Aachen Technical University, 116 pp (1988)
Kross, G.: Die Exploration der Goldlagerstätte Rodalquilar, SE-Spanien. In: Edelmetalle, Schriftenreihe der DGMB 44:117–124 (1986)
Lodder, W.: Gold-alunite deposits and zonal wall-rock alteration near Rodalquilar. Univ. Amsterdam, Geol. Inst., Modeling 318:93 pp (1966)
Lopez-Ruiz, J., Rodriguez Badiola, E.: La region volcanica neogena del sereste de Espana. Estudios Geol. 36:5–63 (1980)
Martin Vivaldi, J.L., Sierra, J., Leal, G.: Some aspects of the mineralization and wall-rock alteration in the Rodalquilar gold field, S.E. Spain. In: Proc. IMA-IAGOD Meetings '70, Joint Symp. Vol. Soc. Mining Geol. Japan, Spec. Issue 2:145–152 (1971)
Potter, R.W. II, Clynne, M.A., Brown, D.L.: Freezing point depression of aqueous sodium chloride solutions. Econ. Geol. 73:284–285 (1978)
Rytuba, J.J., Arribas, A. Jr., Cunningham, C.G., Podwysocki, M.H., McKee, E.H., Arribas, A.: Rodalquilar deposits, Spain, first example of caldera-related epithermal gold mineralization in Europe: Part 1, caldera evolution. In: GSA Annual Meeting, Geol. Soc. of Am., 1988 Centennial Meeting, A351 (1988)
Seward, T.M.: The transport and deposition of gold in hydrothermal systems. In: Foster, R.P. (Ed.), Gold '82: The geology, geochemistry and genesis of gold deposits. A.A. Balkema; Rotterdam 165–182 (1984)
Stoffregen, R.: Genesis of acid-sulfate alteration and Au-Cu-Ag mineralization at Summitville, Colorado. Econ. Geol. 82:1575–1591 (1987)
Torres-Roldan, R.L., Poli, G., Peccerillo, A.: An Early Miocene arc-tholeiitic magmatic dike event from the Alboran Sea — Evidence for precollisional subduction and back-arc crustal extension in the westernmost Mediterranean. Geol. Rundschau 75:219–234 (1986)
Venturelli, G., Capedri, S., Di Battistini, G., Crawford, A., Kogarko, L.N., Clestini, S.: The ultrapotassic rocks from southeastern Spain. Lithos 17:37–54 (1984).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Oepen, P.Sv., Friedrich, G. & Vogt, J.H. Fluid evolution, wallrock alteration, and ore mineralization associated with the Rodalquilar epithermal gold-deposit in southeast Spain. Mineral. Deposita 24, 235–243 (1989). https://doi.org/10.1007/BF00206385
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00206385