Rio de la Plata craton Moho Deep (according to Feng et.al., data: JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 112, B04312, doi:10.1029/2006JB004449, 2007 ). Durrheim & Mooney (GEOLOGY, V. 19, p. 606-609, 1991) analyzed the Archean and Proterozoic provinces throughout the world and they found that the thickness of the crust in Archean provinces is generally about 35 Km (except at collisional boundaries), whereas Proterozoic crust has a significantly greater thickness of about 45 Km. So, in this vision, the Rio de la Plata craton (and in they specially the Rio Apa block) Moho deep is similar to the others Archean world cratons.

Rio de la Plata Craton in gravimetric setting (Marine Gravity Anomalies).

View of Superficial Heat Flow-data in a Tomographic image of the lithospheric mantle derived from seismic S-wave data (Rocha, 2008) at a depth of 150km (Vs is more sensitive to temperature) from Rio de la Plata Craton. Cool = blue balls (pale-blue < 45 and blue 45-50) and hot = red balls (red-orange 50-55 and red >55).

Paraguay-Argentina-SE Central Brazil tomographic image of the lithospheric mantle derived from seismic velocity (P-wave) perturbations at (top) 150 km and (bottom) 300 km depth (Rocha, 2008) =Rio de la Plata Craton.

Parana Basin-area profile line (W-W")(Rocha, 2008)between the Rio de la Plata craton, the Paranapanema block and the San Francisco craton.

Vertical cross-sections along profile W-W" (P-wave)(Rocha, 2008) shown in the up panel (Vp is more sensitive to mantle composition = fast velocity is view as depleted-mantle).

Vertical cross-sections along profile W-W"(S-wave)(Rocha, 2008) shown in the up panel. However, as it was already commented in the previous page, calculations of seismic velocities for mantle-derived xenoliths show that variations in mantle composition can account for as much as 25-percent; of the observed velocity range (Deen et al., 2006 (GEMOC publication #423, In: Research GEMOC highlights 2005).

Eastern-Paraguay (Rio Apa Cratonic Block) Dykes-swarm and kimberlites/alluvial-diamonds (Rio de la Plata Craton). Alluvial diamonds as blue-figures.

Source: http://www.serg.unicam.it/Gravity.htm; http://topex.ucsd.edu/WWW_html/mar_grav.html; http://www.ssme.gov.py/VMME/VMME.htm; http://www.latinamericanminerals.com/Home.html; http://www.on.br/; http://www.heatflow.und.edu/; http://www.cprm.gov.br/; Comin-Chiaramonti, et al. (2007) (http://www.largeigneousprovinces.org/record.html) and, references here.; Druecker, M.D. & Gay, S.P., Jr. (1987). Mafic dyke sarms associated with Mesozoic rifting in Eastern Paraguay, South America. In: H.C. Halls & Fahrig A.R. (Eds.), Mafic dyke swarms, Geological Association of Canada, Sp. Publ., 187-193.; Faure, S. 2006. World Kimberlites CONSOREM Database Version 2006-2. Consortium de Recherche en Exploration Minerale CONSOREM, Universite du Quebec a Montreal, Numerical Database on www.consorem.ca. Unpublished dates and others.; PRESSER, J.L.B. (1992). Geologia da Folha 5569-III La Colmena, Paraguai Oriental. Sao Paulo, 205p. Diss. de Mestrado, IG-USP.; PRESSER, J.L.B. (1998). Feicoes Mineralogicas de rochas lamprofiricas Mesozoicas da Provincia Alcalina Central, Paraguai Oriental. Sao Paulo, 355p Tese de Doutoramento, IG-USP.; Rocha, M.P., 2008. Tomografia sismica com ondas P e S para o estudo do manto superior no Brasil, PHD thesis, IAG, University of Sao Paulo, Sao Paulo (in Portuguese).; Heintz, M., Debayle, E. and Vauchez, A., 2005. Upper mantle structure of the South American continent and neighboring oceans from surface wave tomography. Tectonophysics 406 (2005) 115–139.; Earth and Planetary Science Letters 253 (2007) 17 - 36.; And others.

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