Crustal thickness map of Brazil: Data compilation and main features

Assumpção, Marcelo; Bianchi, Marcelo; Julià, Jordi; Dias, Fábio Luís Ferreira; França, George Sand; Nascimento, R. M.; Drouet, Stéphane; Pavão, Cesar Garcia; Albuquerque, Diogo Farrapo; Lopes, Ângela Célis de Almeida

doi:10.1016/j.jsames.2012.12.009

Cited by 116 publications

(95 citation statements)

References 44 publications

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“…Seismic receiver functions suggest that the current crustal thickness of the Araçuaí-Ribeira belt is ∼ 32-41 km (Assumpção et al, 2013). Considering the pressure estimates obtained in this study and by Munhá et al (2005) for the minimum conditions for metamorphic peaks of the migmatitic kinzigites (650-700 MPa), we can infer that approximately 25 km of the continental crust thickness have been removed.…”

Section: Discussionmentioning

confidence: 56%

Thermal conditions during deformation of partially molten crust from TitaniQ geothermometry: rheological implications for the anatectic domain of the Araçuaí belt, eastern Brazil

et al. 2014

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Abstract. During the Neoproterozoic orogeny, the middle crust of the Araçuaí belt underwent widespread partial melting. At the regional scale, this anatectic domain is characterized by a progressive rotation of the flow direction from south to north, suggesting a 3-D deformation of the anatectic middle crust. To better determine whether melt volumes present in the anatectic middle crust of the Araçuaí orogen were large enough to allow a combination of gravity-driven and convergence-driven deformation, we used the titaniumin-quartz (TitaniQ) geothermometer to estimate the crystallization temperatures of quartz grains in the anatectic rocks. When possible, we compared these estimates with thermobarometric estimates from traditional exchange geothermobarometers applied to neighboring migmatitic kinzigites. TitaniQ temperatures range from 750 to 900 • C, suggesting that quartz starts crystallizing at minimum temperatures of ≥ 800 • C. These results, combined with the bulk-rock chemical composition of diatexites, allows the estimation of a minimum of ∼ 30 % melt and a corresponding viscosity of ∼ 10 9 -10 10 Pa s. Such a minimum melt content and low viscosity are in agreement with interconnected melt networks observed in the field. Considering that these characteristics are homogeneous over a wide area, this supports the finding that the strength of the middle crust was severely weakened by extensive partial melting, making it prone to gravitydriven flow and lateral extrusion.

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Section: Discussionmentioning

confidence: 56%

Thermal conditions during deformation of partially molten crust from TitaniQ geothermometry: rheological implications for the anatectic domain of the Araçuaí belt, eastern Brazil

et al. 2014

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“…Gravimetric and seismic data show that the thickness of the continental crust in the area of the Parnaíba basin does not exceed 40 km (Assumpção et al 2013, Castro et al 2014 with Moho at shallow to intermediate depths in the northeast and central portions of the basin. The boreholes of the present study are located in this area (Fig.…”

Section: Geological Framework Of the Parnaíba Basinmentioning

confidence: 95%

The petrogenesis of tholeiitic diabases in eastern Parnaíba Basin: evidence for geochemical heterogeneities in the subcontinental lithospheric mantle in NE Brazil

et al. 2017

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“…Several isolated crustal thicknesses estimates available in the literature, obtained with different geophysical methods and data types, were superimposed to the 3-D Moho image (Figure 7). Those estimates come basically from seismic ( [40]- [43]) and gravimetric methods ( [44]). In general, we observe a good agreement between our 3-D Moho image and those estimates.…”

Section: Three-dimensional Image Of Mohorovičić Discontinuity In Nortmentioning

confidence: 99%

“…In conclusion, CRUST2.0 global model does not show any relevant variation in Moho depth from one geological province to another and this result does not reflect the complex geological reality of the region ( [46]). Three-dimensional Moho image of the northeastern Brazil based on the methodology proposed in this study, and some isolated crustal thicknesses obtained via seismic (square-28 km [41]; triangle-40 km [40]; red numbers [42]; black numbers [43]) and gravimetric methods (white isolines [44]). Numbers close to the isolines are the corresponding crustal thicknesses.…”

Section: Three-dimensional Image Of Mohorovičić Discontinuity In Nortmentioning

confidence: 99%

Three-Dimensional Shear Wave Velocity Structure of the Northeastern Brazilian Lithosphere

Souza¹,

Santos²,

Vilar³

2016

IJG

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Crustal thickness map of Brazil: Data compilation and main features

Cited by 116 publications

References 44 publications

Thermal conditions during deformation of partially molten crust from TitaniQ geothermometry: rheological implications for the anatectic domain of the Araçuaí belt, eastern Brazil

Thermal conditions during deformation of partially molten crust from TitaniQ geothermometry: rheological implications for the anatectic domain of the Araçuaí belt, eastern Brazil

The petrogenesis of tholeiitic diabases in eastern Parnaíba Basin: evidence for geochemical heterogeneities in the subcontinental lithospheric mantle in NE Brazil

Three-Dimensional Shear Wave Velocity Structure of the Northeastern Brazilian Lithosphere

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