PorterGeo New Search GoBack Geology References
El Romeral
Main commodities: Fe

Our Global Perspective
Series books include:
Click Here
Super Porphyry Cu and Au

Click Here
IOCG Deposits - 70 papers
All papers now Open Access.
Available as Full Text for direct download or on request.
The El Romeral magnetite-apatite deposit is located 22 km north of the Chilean coastal town of La Serena and is one of the largest and best known of the deposits of the Chilean Iron Belt which lies within the Coastal Cordillera of Chile and is associated with the Atacama Fault Zone.

The Chilean Iron Belt is around 30 km wide and extends over a north-south interval of approximately 600 km. It embraces a large number of magnetite-apatite accumulations, some of which are mined for iron on a large scale.

The host rocks at El Romeral include late Palaeozoic schists, phyllites and quartzite, cut by Cretaceous andesite porphyry and diorite. The diorite predates the magnetite ores which were accompanied by pervasive actinolitisation at temperatures in the range 475 to 550° C. Magnetite emplacement was also accompanied by sinistral movement on the Romeral Fault, and by intra-mineral diorite-aplite dykes in fault movement induced gash fractures, and then by post mineral chloritisation.

El Romeral has two main orebodies composed of magnetite microscopically intergrown with actinolite. The Main orebody is a steeply dipping, lenticular magnetite rich mass in a re-entrant between two lobes of the Romeral diorite pluton. The North orebody comprises conformable pods of magnetite within steeply foliated actinolite rich biotite schists. Both have a northerly trend within a north trending network of anastomosing strike-slip faults, and are sub-parallel and adjacent to the western lobe of the diorite pluton. Both orebodies have gradational boundaries with the enclosing rocks which also contain magnetite, actinolite, plagioclase, diopside, clinozoisite, titanite, chlorapatite, mariolitic scapolite, tourmaline, chlorite, pyrite, calcite, micas and clay.

The Main orebody had dimensions of 850x250 m maximum and extended to a depth of 400 m, with 20 to 70% Fe grades. The North orebody outcropped over a distance of 300 m, was 20 to 50 m thick and extended down dip for 100 m. The South-east extension is some 500 m to the south of the Main Orebody and is 800 m long and 100 m wide, although its top is 175 m below the surface. Prior to mining the orebodies were estimated to comprise around 200 Mt of ore. Reserves in 2000 were 44 Mt @ 49% Fe. The mine capacity was 4 Mt of ore per annum. The mine is controlled and operated by Compania Minera del Pacifico S.A..

The most recent source geological information used to prepare this decription was dated: 2001.    
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd.   Unauthorised copying, reproduction, storage or dissemination prohibited.

  References & Additional Information
   Selected References:
Bookstrom A A   1977 - The magnetite deposits of El Romeral, Chile: in    Econ. Geol.   v72 pp 1101-1130
Chen H,  2010 - Mesozoic IOCG Mineralisation in the Central Andes: an Updated Review: in Porter T M, (Ed),  2010 Hydrothermal Iron Oxide Copper-Gold and Related Deposits: A Global Perspective PGC Publishing, Adelaide   v.3 pp. 259-272
Huang, X.-W. and Beaudoin, G.,  2019 - Textures and Chemical Compositions of Magnetite from Iron Oxide Copper-Gold (IOCG) and Kiruna-Type Iron Oxide-Apatite (IOA) Deposits and Their Implications for Ore Genesis and Magnetite Classification Schemes: in    Econ. Geol.   v.114, pp. 953-979.
Palma, G., Barra, F., Reich, M., Simon, A.C. and Romero, R.,  2020 - A review of magnetite geochemistry of Chilean iron oxide-apatite (IOA) deposits and its implications for ore-forming processes: in    Ore Geology Reviews   v.126, doi.org/10.1016/j.oregeorev.2020.103748.
Rojas, P.A., Barra, F., Reich, M., Deditius, A., Simon, A., Uribe, F., Romero, R. and Rojo, M.,  2018 - A genetic link between magnetite mineralization and diorite intrusion at the El Romeral iron oxide-apatite deposit, northern Chile: in    Mineralium Deposita   v.53, pp. 947-966.
Tornos, F., Hanchar, J.M., Munizaga, R., Velasco, F. and Galindo, C.,   2021 - The role of the subducting slab and melt crystallization in the formation of magnetite-(apatite) systems, Coastal Cordillera of Chile: in    Mineralium Deposita   v.56, pp. 253-278.
Williams, P. J., Kendrick, M.A. and Xavier, R.P.,  2010 - Sources of Ore Fluid Components in IOCG Deposits: in Porter T M, (Ed), 2010 Hydrothermal Iron Oxide Copper-Gold and Related Deposits: A Global Perspective PGC Publishing, Adelaide   v.3, pp. 107-116.

Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge.   It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published.   While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo, its employees and servants:   i). do not warrant, or make any representation regarding the use, or results of the use of the information contained herein as to its correctness, accuracy, currency, or otherwise; and   ii). expressly disclaim all liability or responsibility to any person using the information or conclusions contained herein.

Top | Search Again | PGC Home | Terms & Conditions

PGC Logo
Porter GeoConsultancy Pty Ltd
 Ore deposit database
 Conferences & publications
 International Study Tours
     Tour photo albums
PGC Publishing
 Our books and their contents
     Iron oxide copper-gold series
     Super-porphyry series
     Porphyry & Hydrothermal Cu-Au
 Ore deposit literature
 What's new
 Site map