A magnetotelluric survey comprising 18 broadband stations disposed along a 450 km-long profile was carried out at the transition between the Chaco-Paraná (CPB) and the Paraná (PB) intracratonic basins in northeastern Argentina. Three-dimensional inversions of the responses show that the CPB and southern PB lithospheres are resistive (~10³ Ω m) down to 120 km, but with distinct crustal and upper mantle electrical properties. Also, Bouguer gravity and density anomalies are positive at CPB, whereas they are negative at PB. We associate the CPB lithosphere with the Paleoproterozoic Rio Tebicuary craton and the southern PB lithosphere with an ancient and buried piece of craton, the Southern Paraná craton. Geochemical data of mantle xenoliths from the Cenozoic alkaline/carbonatitic province within the Rio Tebicuary craton suggest a subcontinental lithospheric mantle affected by metasomatic processes, which explains its lower resistivity (reaching values as low as 300 Ω m) and higher density (#Mg = 0.87). In contrast, the Southern Paraná craton is more resistive (>10³ Ω m) and less dense, suggesting a de-hydrated, depleted, and thicker craton. These cratons are separated by a crustal conductor (15 to 20 km depth; 1–10 Ω m) that we interpret as a southward continuation of a linear anomaly (Paraná Axial Anomaly) defined in former induction studies within the PB in Brazil. Hence, we redefined the trace of this conductive lineament: instead of bending towards the Torres Syncline, it continues inside the CPB. We propose the lineament to be an Early Neoproterozoic suture zone that controlled the location of maximum subsidence in the intracratonic basins during the Paleozoic. In the Early Cretaceous, the Paraná Axial Anomaly was the site of maximum extrusion and deposition of Serra Geral basalts. This anomaly separates compositionally distinct cratonic lithospheres along its path. Melting of this heterogeneous and enriched mantle created the Paraná igneous province.

在阿根廷东北部的查科-帕拉纳（CPB）和巴拉那（PB）克拉通盆地之间的过渡地带，进行了大地电磁测量，包括沿450公里长的剖面布置的18个宽带站。响应的三维反演表明，CPB和南部PB岩石圈是电阻性的（〜10 ³ Ωm）至120 km，但具有独特的地壳和上地幔电学性质。同样，布格重力和密度异常在CPB处为正，而在PB处为负。我们将CPB岩石圈与古元古代里约热比丘里克拉通联系在一起，将南部PB岩石圈与一个古老的埋藏的克拉通，即南部Paraná克拉通联系起来。来自里奥第三纪克拉通内新生代碱/碳酸盐岩省的地幔异岩的地球化学数据表明，亚陆岩石圈地幔受到交代作用的影响，这说明其电阻率较低（达到低至300Ωm），密度较高（#Mg = 0.87） ）。相比之下，南巴拉那克拉通更具抵抗力（> 10 ³ Ωm）且密度较低，表明克拉通脱水，枯竭且较厚。这些克拉通被地壳导体（深度15至20 km； 1–10Ωm）隔开，我们将其解释为巴西PB以前的归纳研究中定义的线性异常（帕拉纳轴向异常）的向南延续。因此，我们重新定义了该导电线的迹线：它不向Torres Syncline弯曲，而是在CPB内继续延伸。我们建议该系为早新元古代缝线带，该缝带控制古生代克拉通盆地内最大沉降的位置。在早白垩世，巴拉那轴向异常是塞拉杰拉尔玄武岩最大程度地挤出和沉积的地方。这种异常沿其路径将成分不同的克拉通岩石圈分开。