| Full text | |
| Author(s): |
Morales Camera, Matias M.
[1, 2]
;
Dahlquist, Juan A.
[1, 2]
;
Ramacciotti, Carlos D.
[1, 2]
;
Galindo, Carmen
[3]
;
Basei, Miguel A. S.
[4]
;
Zandomeni, Priscila S.
[1, 2]
;
Macchioli Grande, Marcos
[5, 6]
Total Authors: 7
|
| Affiliation: | [1] Univ Nacl Cordoba, Fac Ciencias Exactas Fis & Nat, Av Velez Sarsfield 1611, Cordoba - Argentina
[2] Consejo Nacl Invest Cient & Tecn, Ctr Invest Ciencias La Tierra CICTERRA, Av Velez Sarsfield 1611, Cordoba - Argentina
[3] Univ Complutense, Dept Petrol & Geoquim, E-28040 Madrid - Spain
[4] Univ Sao Paulo, Inst Geociencias, Rua Do Logo 562, BR-05508080 Sao Paulo, SP - Brazil
[5] INGeReN CENIIT UNLaR, Av Gob Vernet & Apostol Felipe, RA-5300 La Rioja - Argentina
[6] Prov La Rioja UNLaR SEGEMAR UNCa CONICET, Ctr Reg Invest Cient & Transferencia Tecnol La Ri, Entre Rios & Mendoza S-N, RA-5301 Anillaco - Argentina
Total Affiliations: 6
|
| Document type: | Journal article |
| Source: | Journal of South American Earth Sciences; v. 88, p. 551-567, DEC 2018. |
| Web of Science Citations: | 1 |
| Abstract | |
The largest igneous body in the Sierras Pampeanas (the Achala batholith) is composed by several magmatic intrusions. How many plutons form this batholith and its intrusive history remains unclear. The emplacement of the batholith began at ca. 380 Ma; the Characato suite, in the northern extreme of the body, represents a relatively young intrusive phase in its construction (ca. 360 Ma). This suite, composed mainly of two-mica monzogranites, correspons to a strongly peraluminous A type magma (A/CNK > 1.1) with fractionated compositions (high Rb/Sr and Rb/Ba). The parental magma corresponds to a high temperature melt generated by biotite dehydration melting, which was then differentiated to form the Characato monzogranites. These monzogranites have crustal Nd- and Sr-isotope signatures (epsilon Nd-t -6.0 to -6.1 and Sr-87/Sr-86(t) 0.7074 to 0.7131) and abundant inherited zircons (ca. 90%). The inherited ages are mainly Early Cambrian, and to a lesser extent Mesoproterozoic, Neoproterozoic and Ordovician, all they recognized in the basement of the Sierras de C6rdoba. The Nd-isotope composition, added to the inherited zircon ages of the Characato suite, indicate that these magmas derived from partial melting of a heterogeneous crust composed by the S-type Pampean granites and migmatites, Famatinian granitoids, and probably the low-to medium-grade metamorphic rocks of the Puncoviscan Series. The high variability and positive epsilon Hf-t values of the inherited Cambrian zircons found in the Characato suite could have been transferred from the Neoproterozoic grains of the Puncaviscana Series to the Early Cambrian S-type granites and migmatites during the Pampean orogeny. (AU) | |
| FAPESP's process: | 18/06837-3 - U-Pb zircon geochronology and HF data from magmatic zircon in devonian-carboniferous granites as monitors of crustal growth and geodynamic setting, pre-andean continental margin of SW Gondwana |
| Grantee: | Miguel Angelo Stipp Basei |
| Support Opportunities: | Research Grants - Visiting Researcher Grant - International |