Abstract
The El Abra porphyry copper deposit belongs to the Late Eocene—Early Oligocene metallogenic belt of northern Chile, which host several world-class porphyry copper deposits. Our previous geochronological work done on this deposit provides the temporal framework for petrological data interpretation. The magmatic history of the El Abra deposit lasts for ~8.6 Ma and can be divided into two stages. An early period, from about 45 to ~38.7 Ma, dominated by diorites and quartz monzodiorites with “normal” (non-adakite) arc geochemistry and a late period, with rocks younger than ~38.7 Ma that developed adakite-like geochemistry, where equigranular granodiorites are the volumetrically dominant rock type (e.g., Clara granodiorite ~38 Ma). These granodiorites are then intruded by leucocratic porphyry dikes and aplites. Most copper mineralization is associated with multiple intrusions of these younger porphyritic rocks, described as the El Abra porphyry unit, and emplaced over a ~1.4 Ma period, from ~37.5 to 36.1 Ma. The adakite-like geochemistry of the younger rock units (<38.7 Ma) is attested by a significant depletion in REE contents, particularly MREE and HREE (concave MREE distribution patterns), high La/Yb and Sr/Y ratios, and Na2O and Al2O3 contents, along with the absence of the Eu anomaly in normalized REE distribution patterns. The evolution of this large, long-lived magmatic system from “normal” to adakite-like arc magmatism is discussed in a tectonic context of crust overthickening due to a major orogenic episode (Incaic compressive phase). This tectonic setting may have promoted higher pressure conditions at the lower crust “hot zone” and increased the crustal residence time of derivative melts favoring extensive differentiation leading to water-rich (and oxidized?) felsic melts, where amphibole fractionation played an important role. Strontium, Nd, and Pb isotope data suggest a common mantle source for both the non-adakite and adakite-like rocks. This implies that these two groups of rocks from the El Abra porphyry copper deposit may have largely resulted from the different crustal conditions under which they have evolved.
Similar content being viewed by others
References
Alonso-Perez R, Müntener O, Ulmer P (2009) Igneous garnet and amphibole fractionation in the roots of island arcs: experimental constraints on andesitic liquids. Contrib Mineral Petrol 157:541
Ardila R (2009) Eventos de mineralización de sulfuros en la Mina El Abra, Internal report from Sociedad Contractual Minera El Abra SCMEA, p 54
Ballard JR (2001) A comparative study between the geochemistry of ore-bearing and barren calc-alkaline intrusions. Unpublished PhD. thesis, The Australian National University, Canberra, p 254
Ballard JR, Palin M, Campbell I (2002) Relative oxidation states of magmas inferred from CeIV/CeIII in zircon: application to porphyry copper deposits of northern Chile. Contrib Mineral Petrol 144:347–364
Barrett LF (2004) Geology and status of exploration projects, El Abra District, II Region, Chile. Internal SCMEA report, El Abra. p 6–37
Bertrand G, Guillou-Frottier l, Loiselet C (2014) Distribution of porphyry copper deposits along the western Tethyan and Andean subduction zones: Insights from a paleotectonic approach. Ore Geol Rev 60:174–190
Cabrera JM, Rabbia OM, Parra A (2010) Caracterización Petrológica de la Fuente Magmática del Depósito Radomiro Tomic. CODELCO Norte Biennial Conference of Geosciences. Calama, p 1–14
Campbell IH, Ballard JR, Palin JM, Allen C, Faunes A (2006) U–Pb zircon geochronology of granitic rocks from the Chuquicamata-El Abra Porphyry Copper Belt of Northern Chile: Excimer Laser Ablation ICP-MS Analysis. Econ Geol 101:1327–1344
Castillo P, Janney P, Solidum R (1999) Petrology and geochemistry of Camiguin Island, southern Philippines: insights to the source of adakites and other lavas in a complex arc setting. Contrib Mineral Petrol 134:33–51
Chelle-Michou C, Chiaradia M, Béguelin P, Ulianov A (2015) Petrological evolution of the magmatic suite associated with the Coroccohuayco Cu(–Au–Fe) Porphyry-Skarn Deposit, Peru. J Petrol 56:1829–1862
Chiaradia M (2014) Copper enrichment in arc magmas controlled by overriding plate thickness. Nat Geosci 7: 43–46
Chiaradia M, Merino D, Spikings R (2009) Rapid transition to long-lived deep crustal magmatic maturation and the formation of giant porphyry-related mineralization Yanacocha, Peru. Earth Planet Sci Lett 288:505–515
Chiaradia M, Ulianov A, Kouzmanov K, Beate B (2012) Why large porphyry Cu deposits like high Sr/Y magmas? Nature 685:1–7
Cornejo P, Mpodozis C, Mora R (2014) Geologic map of the Collahuasi-Calama belt. Antofagasta Minerals, SA
Correa K, Rabbia O, Hernandez L, Selby D, Astengo M (2016) The timing of magmatism and ore formation in the El Abra porphyry copper deposit, northern Chile: Implications for long-lived multiple-event magmatic-hydrothermal porphyry systems. Econ Geol 111:1–28
Dilles JH, Tomlinson A, Marti MW, Blanco N (1997). El abra and fortuna compleexes: a porphyry copper batholith sinistrally displaced by the falla oeste. VIII Congreso Geológico Chileno Actas, vol III:1883–1887
Dilles J, Tomlinson A, García M, Alcota H (2011) The geology of the Fortuna Granodiorite Complex, Chuquicamata district, northern Chile: Relation to porphyry copper deposits. SGA Biennial Meeting, 11th, Antofagasta, Proceedings 399–401
Dreher ST, Macpherson CG, Pearson DG, Davidson JP (2005) Re–Os isotope studies of Mindanao adakites: Implications for sources of metals and melts. Geology 33:957–960
Grove TL, Elkins-Tanton LT, Parman SW et al (2003) Fractional crystallization and mantle-melting controls on calc-alkaline differentiation trends. Contrib Mineral Petrol 145:515–533
Haschke MR (2002) Evolutionary geochemical patterns of Late Cretaceous to Eocene arc magmatic rocks in North Chile: implications for Archean crustal growth. EGU Stephan Mueller Special Publication Series 2 207–218
Hedenquist JW, Lowenstern JB (1994) The role of magmas in the formation of hydrothermal ore deposits. Nature 370:519–527
Hellstrom J, Paton C, Woodhead JD, Hergt JM (2008) Iolite: software for spatially resolved LA-(quad and MC) ICPMS analysis. In: Laser ablation ICP–MS in the earth sciences: current practices and outstanding issues. In: Sylvester P (ed) Mineral Assoc of Canada Short Course series 40:343–348
Henderson P (2013) Developments in geochemistry, volume 2: rare earth element geochemistry presents the remarkable developments in the chemistry and geochemistry of the rare earth elements. Elsevier, Amsterdam, p 510 (ISBN 9781483289779)
Irvine TN, Baragar WRA (1971) A guide to the chemical classification of the common volcanic rocks. Can J Earth Sci 8:523–548
Jochum KP, Stoll B, Herwig K, et al (2006) MPI-DING reference glasses for in situ microanalysis: new reference values for element concentrations and isotope ratios. Geochem Geophys Geosyst 7(2):Q02008
Kay SM, Mpodozis C (2001) Central Andean ore deposits linked to evolving shallow subduction systems and thickening crust. GSA Today 11:4–9
Kay SM, Mpodozis C (2002) Magmatism as a probe to the Neogene shallowing of the Nazca plate beneath the modern Chilean flat-slab. J South Am Earth Sci 15:39–57
Kay S, Mpodozis C, Ramos VA, Munizaga F (1991) Magma source variations for mid-Tertiary magmatic rocks associated with a shallowing subduction zone and a thickening crust in the Central Andes (28–33S). In: Harmon RS, Rapela CW (eds) Andean magmatism and its tectonic setting, Boulder, Colorado. Spec Pap Geol Soc Am 265:113–137
Kurtz AC, Kay SM, Charrier R, Farrar E (1997) Geochronology of Miocene plutons and exhumation history of the El Teniente region, Central Chile (34°-35°S). Rev Geol Chile 24(1):75–90
Le Bas MJ, Le Maitre RW, Streckeisen A, Zanettin B (1986) A chemical classification of volcanic rocks based on the total alkali-Silica diagram. J Petrol 27:745–750
Loucks RR (2014) Distinctive composition of copper-ore-forming arc magmas. Aust J Earth Sci 61:5–16
Maksaev V, Zentilli M (1999) Fission track thermocornology of the Domeyko Cordillera, Northern Chile: implications for Andean tectonics and porphyry copper metallogenesis. Explor Min Geol 8:65–89
Mpodozis C, Cornejo P (2012) Cenozoic tectonics and porphyry copper systems of the Chilean Andes. Soc Eco Geo Spc Pub 16:329–360
Mpodozis C, Marinovic N, Smoje I, Coutiño L (1993) Estudio geológico estructural de la cordillera de Domeyko entre Sierra Limón Verde y Sierra Mariposas, región de Antofagasta: Servicio Nacional de Geología y Minería – Corporación Nacional del Cobre (Chile), Informe registrado IR-93-04, p 282
Oyarzun R, Márquez A, Lillo J, López I, Rivera S (2001) Giant versus small porphyry copper deposits of Cenozoic age in northern Chile: adakite versus normal calc-alkaline magmatism. Miner Depos 36:794–798
Perelló J, Carlotto V, Zárate A, Ramos P, Posso H, Neyra C, Caballero A, Fuster N, Muhr R (2003) Porphyry-style alteration and mineralization of the middle Eocene to early Oligocene Andahuaylas-Yauri belt, Cuzco region, Peru. Econ Geol 98:1575–1605
Petford N, Gallagher K (2001) Partial melting of mafic (amphibolitic) lower crust by periodic influx of basaltic magma. Earth Planet Sci Lett 193:483–499
Pettke T, Oberli F, Heinrich CA (2010) The magma and metal source of giant porphyry-type ore deposits, based on lead isotope microanalysis of individual fluid inclusions. Earth Planet Sci Lett 296:267–277
Pietranik A, Koepke J, Puziewicza J (2006) Crystallization and resorption in plutonic plagioclase: implications on the evolution of granodiorite magma Gęsiniec granodiorite, Strzelin Crystalline Massif, SW Poland. Lithos 86:260–280
Rabbia OM. Hernández LB (2000) Quartz diorite trend in porphyry copper deposits: underlying petrological processes and implications in copper metalogenesis. Miner Metalog 6:416–423
Rabbia OM, Hernández LB, King RW, López-Escobar L (2002) Discusión on “Giant versus small porphyry copper deposits of Cenozoic age in northern Chile: adakite versus normal calc-alkaline magmatism” by Oyarzun et al. (Miner Depos 36:794–798, 2001). Miner Depos 37:791–794
Rabbia OM, Hernandez LB, Cabrera JM, Ulrich T, Bissig T, Parra A (2012) Evidencias de movilidad de las REE en depósitos tipo pórfido de cobre durante la alteración hidrotermal. Congreso Geológico Chileno, 13, Antofagasta, Chile, 5–9 Agosto 2012:90–92
Rapp RP, Watson EB (1995) Dehydration melting of metabasalt at 8–32 kbar: implications for continental growth and crust–mantle recycling. J Petrol 36:891–931
Renjith ML (2014) Micro-textures in plagioclase from 1994 to 1995 eruption, Barren Island Volcano: evidence of dynamic magma plumbing system in the Andaman subduction zone. Geosci Front 5:113–126
Reutter K, Scheuber E, Helmcke D (1991) Structural evidence of origin parallel strike-slip displacements in the North Chilean Precordillera. Geol Rundsch 80:135–153
Richards JP (2003) Tectono-magmatic precursors for porphyry Cu–Mo–Au deposit formation. Econ Geol 98:1515–1533
Richards JP (2009) Postsubduction porphyry Cu-Au and epithermal Au deposits: products of remelting of subduction-modified lithosphere. Geology 37:247–250
Richards JP (2011) High Sr/Y arc magmas and porphyry Cu ± Mo ± Au deposits: just add water. Econ Geol 106:1075–1081
Richards JP, Kerrich R (2007) Adakite-like rocks: their diverse origins and questionable role in metallogenesis. Econ Geol 102:537–576
Richards JP, Boyce A, Pringle M (2001) Geologic evolution of the Escondida Area, Northern Chile: a model for spatial and temporal localization of porphyry Cu mineralization. Econ Geol 96:271–305
Richards JP (2002) Discussion on “Giant versus small porphyry copper deposits of Cenozoic age in northern Chile: adakite versus normal calc-alkaline magmatism” by Oyarzum et al. (Miner Depos 36:794–798, 2001). Miner Depos 37:788–790
Rohrlach BD, Loucks RR (2005) Multi-million-year cyclic ramp-up of volatiles in a lower crustal magma reservoir trapped below the Tampakan copper-gold deposit by Mio-Pliocene crustal compression in the Southern Philippine, vol 2. In: Porter TM (ed), Super porphyry copper and gold deposits—a global perspective. PGC Publishing, pp 369–407
Rojas G (2015) Petrografía, geoquímica y geocronología del distrito Los Volcanes Conchi, Región de Antofagasta, Chile, Undergraduate thesis, Earth Science Department, Universidad de Concepción, p 139
Rooney TO, Franceschi P, Hall CM (2011) Water-saturated magmas in the Panama Canal region: a precursor to adakite-like magma generation? Contrib Mineral Petrol 161:373–388
Santana, CA (2010) Informe estudio geológico-estructural y su aplicación a la exploración de cuerpos mineralizados en el distrito El Abra: Internal report from El Abra Company (SCMEA), p 25
Schütte P, Chiaradia M, Beate B (2011) Petrogenetic evolution of arc magmatism associated with Late Oligocene to Late Miocene porphyry-related ore deposits in Ecuador. Econ Geol 105:1243–1270
Shannon JR, Walker BM, Carten RB, Geraghty EP (1982) Unidirectional solidification textures and their significance in determining relative ages of intrusions at the Henderson Mine, Colorado. Geology 10:293
Sheppard SMF, Taylor HP (1974) Hydrogen and oxygen isotope evidence for the origin of water in the Boulder Batholith and the Bute ore deposits, Montana. Econ Geol 69:926–946
Shinohara H, Hedenquist JW (1997) Constraints on magma degassing beneath the far southeast porphyry Cu–Au deposit, Philippines. J Petrol 38:1741–1752
Sillitoe RH (1972) A plate tectonic model for the origin of porphyry copper deposits. Econ Geol 67:184–197
Sillitoe RH, Perelló J (2005) Andean copper province: tectonomagmatic settings, deposit types, metallogeny, exploration, and discovery. Econ Geol 100th Anniversary vol: 845–890
Simon AC, Ripley EM (2011) The role of magmatic sulfur in the formation of ore deposits. In: Behrens H, Webster JD (eds) Sulfur in magmas and melts: its importance for natural and technical processes. Mineralogical Society of America and Geochemical Society, Rev Miner Geochem 73:513–578
Skewes MA, Stern CR (1994) Tectonic trigger for the formation of late Miocene Cu-rich breccia pipes in the Andes of central Chile. Geology 22:551–554
Skewes MA, Stern CR (1995) Genesis of the giant Late Miocene to Pliocene Cu deposits of Central Chile in the context of Andean magmatic and tectonic evolution. Int Geol Rev 37:893–909
Sun SS, McDonough WF (1989) Chemical and isotopic systematics of oceanic basalts; implications for mantle composition and processes. In: Saunders AD, Norry MJ (eds) Magmatism in the ocean basins. Geol Soc of London 42:313–345
Tomlinson AJ, Dilles JH, Maksaev V (2001) Application of apatite U-Th/He thermochronometry to the determination of the sense and amount of vertical fault displacement at the Chuquicamata porphyry copper deposit, Chile—a discussion. Econ Geol 96:1307–1309
Williams-Jones AE, Heinrich CA (2005) 100th anniversary special paper: vapor transport of metals and the formation of magmatic-hydrothermal ore deposits. Econ Geol 100:1287–1312
Acknowledgements
We thank Sociedad Contractual Minera El Abra (SCMEA) and Freeport-McMoRan Inc., for funding this research, for the logistic support during field work of the second author and finally for the permission to publish the results. The LA-ICP-MS analyses were financed by AMIRA P-972 project. Denis Thiéblemont and Suzanne Kay are thanked for thorough reviews and constructive comments that helped to improve this paper. Finally we thank Prof. Wolf-Christian Dullo for the editorial handling of the paper.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Rabbia, O.M., Correa, K.J., Hernández, L.B. et al. “Normal” to adakite-like arc magmatism associated with the El Abra porphyry copper deposit, Central Andes, Northern Chile. Int J Earth Sci (Geol Rundsch) 106, 2687–2711 (2017). https://doi.org/10.1007/s00531-017-1454-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00531-017-1454-0