Potential flare-ups and lulls in the multi-stage magmatism of the Dom Feliciano belt, southern Brazil: Evidence from geochemistry and isotopic data

Cruz, Rodrigo Fabiano da; Basei, Miguel Ângelo Stipp; Philipp, Ruy Paulo

doi:10.1016/j.jsames.2023.104205

Cited by 2 publications

(3 citation statements)

References 88 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These processes include The processes of mixing, assimilation and hybridization are common evidence discussed by authors studying the PMC (Bastos et al, 2021;Cruz et al, 2023;Loureiro et al, 2021). Approaching a more regional context, Cruz et al (2023) describe these mixing processes and assimilation of country rocks, suggesting multi-stage magmatism related to episodes of intense magmatic peaks, potentially triggered by changes in the tectonic setting. This study considers the process of flare-ups and lulls in a post-tectonic context, although they presume there was some subducted plate slab in their tectonic model.…”

Section: Tectonic Settingmentioning

confidence: 88%

“…The main tectonic interpretations for these rocks in the literature are (a) oceanic lithosphere subduction (Bastos et al, 2021; Chemale Jr., 2000; Fragoso Cesar, 1991; Philipp, 1998; Philipp et al, 1993), (b) continental collision (Hartmann et al, 2000; Philipp & Machado, 2001) and (c) late to post‐collisional magmas (Bitencourt & Nardi, 2000; Cruz et al, 2023).…”

Section: Discussionmentioning

confidence: 99%

“…Slab rupture and failure are essential components of plate tectonics and a natural consequence of the subduction process (Davies & Von Blanckenburg, 1995;Sacks & Secor Jr, 1990). These processes include The processes of mixing, assimilation and hybridization are common evidence discussed by authors studying the PMC (Bastos et al, 2021;Cruz et al, 2023;Loureiro et al, 2021). Approaching a more regional context, Cruz et al (2023) describe these mixing processes and assimilation of country rocks, suggesting multi-stage magmatism related to episodes of intense magmatic peaks, potentially triggered by changes in the tectonic setting.…”

Section: Tectonic Settingmentioning

confidence: 95%

See 2 more Smart Citations

Slab failure‐related magmatism in the Pinheiro Machado Complex, southern Dom Feliciano Belt, Brazil

Bastos,

Koester,

Lenz

et al. 2024

Geological Journal

View full text Add to dashboard Cite

In the Dom Feliciano Belt, Brazil, the Pinheiro Machado Complex (PMC) includes diorites, tonalites, granodiorites, syenogranites and granites, whose evolution is related to several magmatic pulses and complex petrogenetic processes. Two magmatic stages were identified (early and late), resulting in different rock subgroups. The geochemical data showed that the early magmatism was chemically affected by partial melting. Geochemical modelling results suggest that fractional crystallization processes with assimilation of around 40% from the crustal basement and the decoupling of assimilated magma are crucial for the PMC rocks' genesis. Geochemical data also show that during the early magmatism, the subsequent process of early diorite anatexis developed by heating and continuous activity of the underlying magma chamber possibly occurred at a melting rate of 5%–10%. The hybrid rocks have contributions from the mixing process related to early terms, showing geochemical correlations in the major element curves, for the early diorite and syenogranitic melt members, at 60%–50% and 50%–40%, respectively. Slab failure tectonic context is related to the multi‐intrusive events dynamics recorded in the studied rocks. Recharge and melting events of the recently formed crust due to the constant heating of new pulses of deep slab melting would explain the magmatic interactions observed in the Complex. The results demonstrate that the studied rocks crystallized in an open system, including mixing processes to form hybrid rocks, physical disaggregation and assimilation of early intrusions, truncation, dragging and erosion of early mushes by younger pulses.

show abstract