简介:ThisstudyfocusesonthebasementstructureoftheParanáBasininSouthAmerica,basedongeologicalandgeophysicaldata.ItisalargeintracratonicbasinformedfromtheLateOrdovicianuntiltheCretaceous,whenasequenceofcontinentalfloodbasaltseruptionscoveredtheentirebasin,precedingthebreak-upofWesternGondwana.Isostaticmodelingwasappliedtolargegravitysurveyscomprisingmorethan12,000gravitystations.TheresidualBougueranomalypattern,representingthecrustalcontributionofthecrystallinebasement,aswellasthesedimentaryandvolcaniclayersofthebasin,revealssimilaritiesbetweenthebasementgravitysignatureandtheexposedrock.ThestresspatternsoftheLateOrdovicianandCretaceoustectoniceventspresentageographicallycoincidentmaximum,andthecorrelationbetweengravityhighsandthemainattenuation(betafactor)suggeststhepresenceofsomepreexistentsuturezones.TheresultantmosaicofgravityblocksandthelocationofmajorfaultsgivesupporttothepresenceofanimportantProterozoiccratonicfeature,herereferredtoasParanapanemablock.