No abstract

No abstract

The Campos do Jordão Plateau, on the southwestern border of the main block of the Serra da Mantiqueira presents evidence of recent tectonic reactivations, as expressed by the organization of the drainage network and the presence of morphotecton ic features. Morphometric analyses usually used in morphotectonic studies revealed neotectonic control of the morphology of the plateau. lsovalue maps of drainage density, relief roughness, hydraulic gradients, isobase surface and slope confirm the compartimentalization of the plateau in blocks delimited by the main trend of lineaments. This compartimentalization coincides with the limits of geosystemic units established for the plateau. Morphotectonic featuresriver captures, assymetric valleys with straight scarps, triangular and trapezoidal facets, suspended amphitheaters, shutter ridges, indistinct drainage divides, truncated hill crestsare directly associated with recent faults caused mainly by tectonic reactivation of zones of weakness represented by metamorphic foliation in Precambrian rocks. Morphostructural analysis of the Campos do Jordão Plateau, including characterization of Quaternary deposits and brittle tectonic structures, has led to the identification of three superposed neotectonic regimes. an initial E-W right-lateral transcurrent binary with left-lateral movement of NNW-SSE and right-lateral movement of ENE-WSW ¡/NW-ESE transcurrent faults (Late Pleistocene/Holocene), followed by E-W extension characterized by normal faults and a final E-WNW-SE compression that generated neotectonic joints in colluvium, organic-rich soils and peat deposits, compatible with the present-day horizontal maximum stress obtained from geophysical data. ïhus, the same pattern and ages of the tectonic regimes identified in neighboring areas, such as in the Paraíba do Sul Valley and in the area of the Queluz Structural High, are confirmed for the Campos do Jordão Plateau.