From the morphostuctural and morphotectonic analysis integrated to the informations of remote sensing images, litoestratighaphy , geomorfology , the seismic data and field investigations was defined the neotectonic structuration and its influence in the elaboration of the relief forms and drainage net during the Upper Tertiary and Quaternary. This relation is shown through the morphotectonic compartimentation of the Solimões-Negro watershed, subject of this research (SA.20-Manaus Sheet). The discussions concentrated in the area of the cenozoics covers which overlay the east and west borders of the Solimões and Amazon paleozoics sedimentary basins, respectively. This area occupies about 290 000 km2, and is situated between the parallels 0° and 4° S and meridians 60° and 66° WGr, in the Amazonian region, involving parcels of Amazon and Roraima States. The geologic units formed during, or imediatelly after, the implantation of the neotectonic regimen are represented by: 1) the Içá Formation formed after the Miocene, probably of the Plio-Pleistocene age; 2) the Pleistocenics Terraces; 3) the Holocenics Terraces; 4) the inundatable watersheds areas of holocenic age; and 5) the Holocenics Alluviums. The modelling of the landscape for the drainage net evidences a relief compartimentation at plains systems, linked to the actual fluvial dynamics, and depressions, normally leveled by a planing surface formed in the Middle Pleistocene, in retaken by erosion, and preserved on tabular watershed. The neotectonic structuration has a direct relationship with the regeneration of the discontinuities of the paleotectonic structuration, that is, with the resurgent tectonic . This old estructuration is defined by: 1) Tacutu Lineament of NE-SO orientation, that show continuity to the northwest quadrant of the area; 2) the Madeira Lineament, also of NE-SO orientation that section the Southeastern quadrant; 3) the Purus Arc with NW orientation that establishes the limits between the Solimões and Amazon basin; e (4) minors lineaments as the Juruá and the Japurá ones, of E-O direction, defined outside of the domains of the research area. The neotectonic tensions field was alliviated through two kinematics pulses of essentially transcorrent nature. In the first pulse, occurred immediately after the inversion of the Amazonian Occidental drainage for east, had established the main corridors of drainage in the predominant NE-SO direction through the northeast of Amazonas and Roraima states in the brasilian territory, reaching the Guyana Republic and the Atlantic Ocean through rift valley of the Tacutu. The second one, predominantly transtensive, occurred in the Upper Pleistocene /Holocene, provoked the redirectioning of this system for the Amazonas hidrographic basin, and answers for the actual configuration of the relief and drainage net. The Relief Systems are differentiate for the degree of development of the drainage net, showing a evident gradation from the most evolued to the less evolued, that is reflected in the configuration of the watershed and its dimensiona, and that register the history of the implantation of the neotectonic structural picture and its geometric and kinematic differentiations. This register is represented through five morfotectonics compartments, called: Juruá River - Purus River Tanspressive Compartment; Madeira River - Purus River Transcorrent Compartment; Negro River- Japurá River Trancorrent Compartment; Negro River - Solimões River Trantensive Compartment; and the Branco River- Negro River Transtensive Compartment. The morphostructural and morphotectonic evolution occurred from southwest to northeast. So, the drainage net show best developed in the Juruá River — Madeira River Compartment; it is in development in the central zone formed by the Madeira River - Purus River, Negro River-Japurá River and Negro River- Solimões River Compartments; and show a initial stage of development in the Negro River- Branco River Compartment. In the northeast border of the Negro River Japurá River Transtensive Compartment, the development of the drainage net is composed, showing features of initial stage, as the amorphous and multibasinal pattern, with other typicals features of drainage net in development. The structures of the Juruá River Purus River Compartment are generated by inverse faults in the Upper Tertiary. In the the Madeira River - Purus River and Negro River — Japurá River compartments they are dextrals directional faults with component of oblique slip, probably of the reverse type in the Tertiary Superior and normal in the Pleistocene; in the Negro River - Solimões River Compartment they are mainly normal and oblique-dextrais types in the Upper Pleistocene. The Negro River- Branco River Compartment configures a wedge structure with oblique movement in the northwest and east borders, and extensional in its central zone, with evolution initiated in the Upper Pleistocene extending to the Holocene. Recent activity of some of these faults is marked by seismic events with intensities that arrive 5,5 mB.
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