Tectonics and Sedimentation in the Curitiba Basin, South of Brazil
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Journal of South American Earth Sciences PERGAMON Journal of South American Earth Sciences 15 (2003) 901-910 www.elsevier.comllocate/jsames Tectonics and sedimentation in the Curitiba Basin, south of Brazil b Eduardo Salamuni":", Hans Dirk Ebert , Mauricio da Silva Borges", Yociteru Hasui'', João Batista Sena Costa", Riad Salamuni":" "Departamento de Geologia, Universidade Federal do Paraná, Centro Politécnico, Jardim das Américas, P.O. Box 19001, zip 81530-990 Curitiba, PR, Brasil "Departamento de Petrologia e Metalogenia, Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista, Avenida 24-A, 1515, P. O. Box 178, 13506-900 Rio Claro, SP, Brazil I "Ceruro de Geociências, Universidade Federal do Pará, Campus Universitário do Guamá, P.O Box 1611, 66075-900 Belém; PA, Brazil "lnstituto de Estudos Estratégicos da Amazônia, Avenida Governador José Malcher, 1148, 66055-260 Belém, PA, Brazil Received 1 April 2002; accepted 1 October 2002 Abstract The Curitiba Basin, Paraná, lies parallel to the west side of the Serra do Mar range and is part of a continental rift near the Atlantic coast of southeastern Brazil. It bears unconsolidated and poor1y consolidated sediments divided in two formations: the lower Guabirotuba Formation and the overlying Tinguis Formation, both developed over Precambrian basement. Field observations, water well drill cores, and interpretations of satellite images lead to the inference that regional tectonic processes were responsible for the origin of the Basin in the continental rift context and for morphotecatonic evolution through block tilting, dissection, and erosion. The structural framework of the sediments and the basement is characterized by NE-SW-trending normal fauits (extensional tectonic DI event) reactivated by NE-SW-trending strike-slip and reverse oblique faults (younger transtensional tectonic D2' to transpressional tectonic D2" event). This tectonic event, which started in the Paleogene and controlled the basin geometry, began as a halfgraben and was later reactivated as a pull-apart basin. D2 is a neotectonic event that controls the current morphostructures. The Basin is connected to the structural rearrangement of the South American platform, which underwent a generalized extensional or trantensional process and, in late Oligocene, changed to a compressional to transpressional regime. © 2003 Elsevier Science Ltd. Ali rights reserved. Keywords: Sedimentary basin; Tertiary and Quaternary tectonics; Morphotectonics; Neotectonics Resumo A Bacia de Curitiba, localizada no Estado do Paraná, é paralela à face oeste da Serra do Mar, e faz parte de um rifte continental, próximo à costa atlântica do sudeste do Brasil. É preenchida por sedimentos pouco consolidados a inconsolidados e abrange as formações Guabirotuba, inferior, e Tinguis superior, posicionadas sobre o embasamento pré-cambriano. Com base em observações em campo e imagens de satélite, bem como perfis de sondagem, conclui-se que processos tectônicos regionais propiciaram a origem da Bacia de Curitiba, no contexto do rifte continental e, em um segundo momento, controlaram sua evolução morfotectônica através de basculamento de blocos, dissecamento e erosão. Tanto os sedimentos quanto o embasamento são caracterizados por falhas normais de direção NE-SW (regime extensional DI), posteriormente reativadas como direcionais e inversas oblíquas (regime transtensional D2' a transpressional D2")' Os eventos ocorreram a partir do Paleógeno e definiram a geometria da bacia, iniciada como halfgraben e reativada como bacia pull-apart. O evento Dz também gerou morfoestruturas e caracteriza processos neotectônicos. A bacia está ligada ao rearranjo estrutural da Plataforma Sul-Americana, que sofria inicialmente generalizado processo extensional ou transtensional e passa, a partir do Oligoceno superior, a sofrer processos compressionais e transtensionais. © 2003 Elsevier Science Ltd. All rights reserved. Palavras chaves: Embasamento pré-cambriano; Plataforma Sul-Americana; Compressionais e transtensionais 1. Introduction * Corresponding author. Te!.: +55-41-361-3147; fax: +55-41-361-3642 . .., In Memorian. The Curitiba Sedimentary Basin, which comprises an E-mail addresses:[email protected](E.Salamuni). hdebert@ rc.unesp.br (H.D. Ebert), [email protected] (Y. Hasui), jbsena@iesam. area of approximately 3000 km", is situated in the central- com.br (J.B.S. Costa). southem portion of the Curitiba plateau, Paraná (Fig. 1). It 0895-9811103/$ - see front matter © 2003 Elsevier Science Ltd. Ali rights reserved. doi:1 0.1 016/S0895-981I (03)00013-0 902 E. Salamuni et aI. / Journal of South American Earth Sciences 15 (2003) 901-910 49°25' W D°S N f o 2000 km o 500km 10 km Fig. 1. Location of the Curitiba Sedirnentary Basin. belongs to a larger set of graben known as the continental paper presents such aspects and discusses the formation and rift of southeastem Brazil (Riccomini et al., 1989), which evolution of the Curitiba Basin on the basis of the runs along the Serra do Mar range parallel to the Atlantic sedimentary filling, geomorphology, structures, tectonic coast between Rio de Janeiro and Curitiba (Fig. 2). kinematics, and paleostresses. The Basin is a NE-SW, elongated depression between the northern and central portions of the upper Iguaçu River hydrographic basin with altitudes ranging between 870 and 2. Methods 960 m. It is completely surrounded by Precambrian rocks: the Serra do Mar range in the east and southeast margins and A combination of field data and aerial photo interpret- the Precambrian metasediments of the Açungui group in the ations was used. Structural data, such as fault planes and west and northwest margins. The Basin strata are gently their kinematic indicators, were obtained from the basin tilted toward the S-SW in the direction ofthe Iguaçu River, sediments and, where possible, in sedimentary rocks and the which represents the regional base level. surrounding basement rocks. Data from drill holes also were Urban and industrial growth in the metropolitan region of assembled to understand the three-dimensional architecture Curitiba, as well as prospecting for nonmetallic mineraIs, of the basin sedimentary sequences. has demanded comprehensive hydrological, geotechnical, Surface data were grouped in different morphostructural and environmental studies. For these investigations, detailed domains that characterize homologous zones, defined by lithological and structural information is required. This parameters such as fracture density and orientation and by v, Main leclonic lineaments ~'~ ~ (strlke-slip shear zones) ,,'" -' Paraná Basin boundary v:' Serra do Mar scarpmenl D Cenozoic deposils of lhe Continental Rift basins [V'T""VJ ~ Paraná Basin limi! 40"VV o- Precambrian 50'W 1. Resende Basin 2. Taubaté Basin 3. São Paulo Basin 4. Pariqueraçu Basin 5. Curitiba Basin I--t--"-',;,--t---+---j.- 26"S o 100 km , ! , v, Fig. 2. Main Tertiary basins of the southeastern Brazilian continental rift. Simplified from Schobbenhaus et a!. (1981). E. Salamuni et al. / Journal af South American Earth Sciences 15 (2003) 901-910 903 morphological aspects such as drainage patterns and a nonconforming pattem and consists of greenish clay and physiography. The structural analysis was used to define slightly lithified silty sediments that grade upward or tectonic controls related to the formation of the Basin, its lateral1y to coarser facies, depending on the local structural sedimentary filling, and subsequent deformation. framework. Caliche, arkose, arkosic sand and quartz- The structural analysis focused on the determination of dominated oligomictic gravel deposits form local intercala- principal paleostress axes through the method of right tions. The main facies of the Guabirotuba Formation are as dihedra (Angelier, 1989, 1994) using fault planes and follows: slickensides in each domain. To avoid ambiguous interpret- ations, the structural data were processed separately 1. Massive pelitic facies (Pm) formed mainly of argillac- according to their occurrence along extensional or com- eous and muddy deposits, thicker in the center of the pressive/transpressive faults. Basin and less common on its borders, well compacted, massive, fine-grained, and gray-greenish with white stains or pink where lateritization is evident. 3. Geological setting and morphostructures 2. Psammitic facies (Am) formed of unconsolidated or weakly consolidated deposits of sand diamictons, 3.1. Basin lithostratigraphy andfacies distribution arkoses, and arkosic sands with submillimetric to centimetric, angular and subangular, slightly reworked quartz, quartzite, and feldspar clasts in a silty-sandy, The stratigraphic column of the Curitiba Basin is locally clayey, matrix. The sand layers show tabular and presented in Table 1. The Guabirotuba Formation (Bigarella cross-stratification. The arkosic sands vary from med- and Salamuni, 1962) is the most important unit. It rests ium- to fine-grained in the center and southwest of the unconformably over Precambrian metamorphic rocks of the Basin to coarse-grained in the eastern and northeastern Atuba complex (Siga et al., 1995) and is overlain by the portions. The matrix is generally argillaceous and gray. Tinguis Formation (Becker, 1982) and younger colluvial 3. Massive paraconglomeratic facies (Pm) composed of and alluvial sediments of the Iguaçu River and its angular to subrounded polymictic gravels with a clay tributaries. matrix. ln the southwest and west of the Basin, the The Atuba complex consists of severallithotypes