The Miocene Tatatila-Las Minas IOCG skarn deposits (Veracruz) as a result of adakitic magmatism in the Trans-Mexican Volcanic Belt
Por:
Fuentes-Guzman, Edith, Gonzalez-Partida, Eduardo, CAMPRUBI, ANTONI, Hernandez-Aviles, Geovanny, Gabites, Janet, IRIONDO, ALEXANDER, Ruggieri, Giovanni, Lopez-Martinez, Margarita
Publicada:
1 ene 2020
Categoría:
Earth and planetary sciences (miscellaneous)
Resumen:
The Cu- and Au-rich Tatatila Las Minas IOCG skarn deposits in Veracniz
(central-cast Mexico) are circumscribed to the earliest stages of the
`Trans-Mexican Volcanic Belt (TMVB) and stand for a metallogenic
province directly linked to its tectonomagmatic dynamics. This is the
first well-documented case for such metallogenic province. These
deposits were formed as skarns between rocks of the Mesozoic carbonate
series and Miocene intermediate to acid hypabyssal rocks. yew U-Pb
zircon and Ar-40/Ar-39 ages provide evidence for four epochs of magmatic
activity in the area: (I) early Permian (Artinskian), in association
with the Paleozoic basement, (2) late Oligocene to early Miocene suite
of pre-TMVB intrusive rocks, (3) middle to late Miocene suite of early
TMVB-related intrusive rocks, and (4) Pliocene intrusive and extrusive
rocks of the TMVB, possibly associated with the Los Humeros post-caldera
stage. The obtained ages range between 24.60 +/- 1.10 and 19.04 +/- 0.69
Ma for stage 2, and between 16.34 +/- 0.20 and 13.92 +/- 0.22 Ma for
stage 3. Stage 2 corresponds to a magmatic stage unheard of in the area,
until this study. Only stage 3 rocks are associated with the IOCG skarn
mineralization, with retrograde stages dated at 12.44 +/- 0.09 (chromian
muscovite, phyllic association) and 12.18 +/- 0.21 Ma (zircon, potassic
association). Therefore, the ages of stage-3 intrusive rocks are
interpreted to date the formation of the prograde skarn associations
(mostly similar to 15.4 to <14 Ma) The petrogenetic affinity of stage-2
and stage-3 rocks is about the same the main difference has to do with
higher Y and Yb contents in stage-3 rocks (although no affinity with
within-plate granites was found), which is suggestive of an interaction
of their parental magmas with alkaline magmas that most likely belong to
the conterminous and contemporaneous Eastern Mexico Alkaline Province.
Petrological indicators (elemental and isotopic) in Cenozoic rocks
consistently point to intermediate to acid, metaluminous, I- and S-type
rocks that were emplaced in a subduction-related continental arc, within
the medium- to high-potassium talc-alkaline series, with high-silica
adakitic signatures due associated to deep-sourced magmas that underwent
crustal contamination to some degree. The various possible sources for
the magmas with adakitic signature in this context can be narrowed down
to two of them that are not mutually exclusive: adakitic derived from
subducted slab melting and melting-assimilation-storage-homogenization
(MASK-derived adakites. Both sources are, in principle, capable of
generating magmas that would eventually produce magmatic-hydrothermal
mineralizing systems with an associated variety of ore deposit types,
including IOCG. Also, both possible sources for adakites are compatible
with the renewed steepening of the subducted slab after a period of fiat
subduction, for the earliest stage in the evolution of the TMVB.
Filiaciones:
Fuentes-Guzman, Edith:
Univ Nacl Autonoma Mexico, Inst Geol, Coyoacan 04510, Cdmx, Mexico
Univ Nacl Autonoma Mexico, Programa Posgrad Ciencias Tierra, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Lab Nacl Geoquim & Mineral LANGEM, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Gonzalez-Partida, Eduardo:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
CAMPRUBI, ANTONI:
Univ Nacl Autonoma Mexico, Inst Geol, Coyoacan 04510, Cdmx, Mexico
Lab Nacl Geoquim & Mineral LANGEM, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Hernandez-Aviles, Geovanny:
Univ Nacl Autonoma Mexico, Programa Posgrad Ciencias Tierra, Ciudad Univ, Coyoacan 04510, Cdmx, Mexico
Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Gabites, Janet:
Univ British Columbia, Pacific Ctr Isotop & Geochem Res, Dept Earth Ocean & Atmospher Sci, Earth Sci Bldg,2207 Main Mall, Vancouver, BC V6T 1Z4, Canada
IRIONDO, ALEXANDER:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Univ Arizona, Dept Geosci, 1040 E 4th St, Tucson, AZ 85721 USA
Ruggieri, Giovanni:
CNR, Ist Geosci & Georisorse, Via G Moruzzi 1, I-511124 Pisa, Italy
Lopez-Martinez, Margarita:
Ctr Invest Cient Estudios Super Ensenada, Carretera Tijuana Ensenada Km 107, Ensenada 22860, Baja California, Mexico
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