This thesis develops the Radargraphic Elements Sistematic method, unknown throughout the world, in the geologic interpretation with Side-Looking Radar (Radargeology), a technique of major relevante in the field of natural resources, considering that the 1990s are the Radar's decade. The Radargraphic Elements Sistematic (SER) method reveals in a sistematic form the methodological route adopted , be it trough the text, trough schematic figures, or in Side-Looking Radar (SLR), with the radargraphic elements (features), ordered in five different stages: Reading, Recognizing, Identifying, Analisys and Interpretation (stricto senso). The stage Reading seeks to understand the meaning of the image elements in the terrain, with the goal of understand their meaning ; the Recognizing stages seek to group them according to the texture and tone radargraphic, so as to obtain homogeneous radargraphic zones; Identification seeks to study the relief forms in such zones, with regard to top and pending, as well as the studying of the drainage patterns, dissection degree and erosion resistance ;and the Analysis establishes the spacial and temporal relation of the relief forms researched through linear, planar and tabular features. With such information in hand , the Interpretation stage itself is reach, in which is possible to define lithologies, rounded structures, unconformities, discontinuities, folds and their interrelations,with a view to executing the Radargeological Map.In effect, a model area was selected to serve a paradigm for the the different methodological stages. To apply the Radargraphic Elements Sistematic method, the region encompassed by Parnaíba Sineclyse and its embasement was selected, with an area of around 925 000 km2, involving mostly Maranhão e Piauí states, located in northeastern region of Brazil. Such an example seeks to emphasys the applicability of the remote sensing in sedimentar terrains and their metamorphic embasement, due to academic and economic importance involved.. To carry out this stage, 52 SLR images mosaics were utilized, scale, I: 250 000, GEMS, X band, resulting in the definition of 39 basic radargeologicals unities, with a temporal stratigraphy, and 19 regional strucutures and 30 local ones, of which more than half were unpublished. These results are expressed in an explanatory text with ilustrations, including a Radargological Map on the milionth scale , and a structural sketch on the scale of 1:2 000 000. The study reaches a favorable conclusion regarding the potentialities of SLR images in geological whose difficulties in defining the radargraphic elements (features) due mainly to extensive shadows, foreshortening , layover and paralaxe effects, will be overcome with the use of more sophisticated Radar Systems (digital mode, stereoscopy, multifrequency, differents angles of incidence,etc) , as is the case with SIR-C and RADARSAT. Finally, the study attests of the excelence of Radargraphic Elements Sistematic method considering the results achieve with the study of the Parnaíba Sineclyse and its embasement, such as : definition of radargeological units, which mantain a strict relation with the lithostratigraphic units already described in the literature; structural setting with the identification of almost 50 morphostructures of regional and local character , and a perfect correlation with aeromagnetic maps.
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