Response of the Apodi-Mossoró estuary-incised valley system (NE Brazil) to sea-level fluctuations

Vital, Helenice; Furtado, Samia F.Lima; Gomes, Moab Praxedes

Abstracts

This study focuses on the Quaternary sea level changes in the Apodi-Mossoró Estuary and adjacent shelf, Northeastern Brazil, based on the analysis of high-resolution seismic profiles, integrated with echosounder, SRTM and satellite image data. We use these data to develop a relative stratigraphy. An incised-valley extending from the Apodi-Mossoró Estuary onto the shelf dominates the investigated area. In very shallow waters (down to 10 m depth) the channel lies mainly in a NW-SE direction, changing to NE-SW in waters below10 m, in the form of a J-shaped valley. The southern flank of the shallow channel presents an abrupt morphology, probably determined by a residual scarp due to neotectonic reactivation of a pre-existing fault. This incised-valley can be correlated with a former river valley formed during the late Pleistocene fall in sea-level. The base-level change related to this drop in sea level can be regionally expressed on seismic lines as a laterally-continuous stratigraphic surface named Horizon I, interpreted as representing the sub-aerial exposure of the continental shelf. Many incised valleys were excavated on this exposed shelf, including that of the Apodi-Mossoró Estuary and its incised valley system. This incised valley has lain buried since the Holocene transgression. The Holocene sediments present sub-horizontal layers, or they have filled the incised valley with oblique features.

NE Brazilian shelf; Mossoró-Apodi Estuary; incised valley; sea-level changes; Seismostratigraphy

Este estudo utiliza a integração de dados sísmicos de alta resolução, batimétricos, SRTM e imagens de satélite para desenvolvimento da estratigrafia relativa visando entender as variações do nível do mar durante o Quaternário no estuário do rio Apodi-Mossoró e plataforma adjacente, nordeste do Brasil. A principal feição identificada foi um canal submerso, na plataforma interna, parcialmente preenchido, provavelmente relacionado com o sistema de vales incisos formado durante o rebaixamento do nível do mar no Pleistoceno. O canal apresenta duas direções principais (NW-SE e NE-SW), em forma da letra J, aparentemente controladas pelas estruturas tectônicas da Bacia Potiguar. A margem oeste do canal é relativamente soerguida em relação à margem leste. Com base nos dados sísmicos foi possível identificar uma descontinuidade presente em toda a área, interpretada como o limite Pleistoceno/Holoceno, bem como sismofácies referentes a padrões de preenchimento e sedimentação do canal submerso e da plataforma durante a subida do nível do mar no Holoceno.

plataforma NE Brasileira; estuário Apodi-Mossoró; vales inciso; mudanças do nível do mar; sismoestratigrafia

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BOYD, R.; DALRYMPLE, R. W.; ZAITLIN, B. A. Estuarine and incised-valley facies models. In: POSAMENTIER, H. W.; WALKER, R. G. (Ed). Facies models revisited Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 84, p. 171-235).
CALDAS, L. H. O.; STATTEGGER, K.; VITAL, H. Holocene sea-level history ; Evidence from coastal sediments of the northern Rio Grande do Norte coast, NE Brazil. Mar. Geol, v. 228, p. 39-53, 2006.
CHAVES, M.; VITAL, H.; SILVEIRA, I. M. Beach morphodynamics of the Serra oil field, northeastern Brazil. J. coast. Res, Special Issue 39, p. 594-597. 2006.
DALRYMPLE, R. W.; BOYD, R.; ZAITLIN, B. A. Incised-valley systems: Origin and sedimentary sequences. Tulsa, Okla.: 1994. (SEPM Spec. Publ., n. 51, p. 03-10).
DALRYMPLE, R.W.; LECKIE, D. A.; TILLMAN, R.W. Incised valleys in time and space Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 85).
LI, C.; WANG, P.; FAN, D.; YANG, S. Characteristics and formation of late Quaternary incised-valley-fill sequences in sediment-rich deltas and estuaries: case study from China. In: DALRYMPLE, R.W.; LECKIE, S. A.; TILLMAN, R.W. (Ed.). Incised valleys in time and space Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 85, p. 141-160).
LIMA, S. F.; VITAL, H. Geomorphological and paleogeographic characterization of continental shelf of the Apodi-Mossoró River, RN-Brazil. In: BREBBIA, C. A.. (Ed.). Environmental problems in coastal regions VI, including oil spill studies Cambridge, GB: Wessex Institute of Technology; Cambridge Printing, Great Britain, 2006. p. 351-360.
LIMA, Z. M. C.; VITAL, H.; TABOSA, W.F. Morphodynamic Variability of The Galinhos Spit, Northeastern Brazil. J. coast Res, Special Issue, 39, p. 598-601, 2006.
LORING, D. H.; RANTALA, R. T. T. Manual for the geochemical analysis of marine sediments and suspended particulate matter. Earth-Sci. Rev., v. 32, p. 235-283, 1992.
MATOS, R. M. D. The northeastern Brazilian rift system. Tectonics, v. 1, p. 767 790, 1994.
MILANI, E. J.; THOMAZ- FILHO, A. Sedimentary basins of South America. In: CORDANI, U. G.; MILANI, E. J.; THOMAZ- FILHO, A.; CAMPOS D. A. (Ed). Tectonic evolution of South america. INTERNATIONAL GEOLOGICAL CONGRESS. 31., Rio de Janeiro, 2000. p. 389-449.
MITCHUM, R. M.; VAIL, P. R.; SANGREE, J. B. Seismic stratigraphy and global changes of sea level. Part 6: Stratigraphic interpretation of seismic reflection patterns in depositional sequences. In: PAYTON, C.E. (Ed.). Seismic Stratigraphy - application to hydrocarbon exploration. AAPG Memoir, n. 26, p. 117- 133, 1977.
PELTIER, W. R. Global glacial isostatic adjustment and coastal tectonics. In: STEWART, I., VITA-FINZI, C. (Ed.). Coastal Tectonics. Geol. Soc. London, 1998. (Special Publ. n. 146, p. 1-29).
PESSOA-NETO, O. C. Análise estratigráfica integrada da plataforma mista (Siliciclástica-Carbonática) do Neogeno da Bacia Potiguar, nordeste do Brasil 244 p. 1999. Dissertação (Mestrado) - Rio Grande do Sul Federal University, Porto Alegre-RS.
PESSOA-NETO, O. C. Estratigrafia de Seqüências da Plataforma Mista Neogênicana Bacia Potiguar, Margem Equatorial Brasileira. Rev. Bras. Geociênc., v. . 33, p. 263-278, 2003.
SANTOS, C. L. A.; VITAL, H.; AMARO, V. E.; KIKUCHY, R. K. P. Mapeamento de recifes na plataforma continental. Nordeste do Brasil: Touros a Maracajau RN. Brazilian J. Geoph, v. 1,p. 1-10, 2007.
SCHWARZER, K.; STATTEGGER, K.; VITAL, H.; BECKER, M. Holocene coastal evolution of the Rio Açu Area (Rio Grande do Norte, Brazil). J. Coast Res, Special Issue n. 39, p. 141-145, 2006.
STATTEGGER, K.; CALDAS, L. H. O.; VITAL, H. Holocene coastal evolution of the Northern Rio Grande do Norte Coast, Brazil. J. Coast. Res, Special Issue n. 39, p. 151-156, 2006.
STEWART, I. S.; HANCOCK, P. L. What is a fault scarp? Episodes, v. 13-4, p. 256-263, 1990.
TABOSA, W. F.; LIMA, Z. M. C.; VITAL, H.; GUEDES, I. M. G. Monitoramento costeiro das praias de São Bento do Norte e Caiçara do Norte NE Brasil. Rev. Pesq. Geoc, v. 28, p. 383-392, 2001.
VITAL, H. Erosão e progradação no litoral do Rio Grande do Norte. In: MUEHE, D. (Org.). Erosão e progradação do litoral brasileiro. Brasilia, DF: Ministério do Meio Ambiente, p.159-176, 2005.
VITAL, H.; STATTEGGER, K.; AMARO, V. E.; SCHWARZER, K.; FRAZÃO, E. P.; TABOSA, W. F. Inner continental shelf off northern Rio Grande do Norte, NE Brazil: A modern high-energy siliciclastic-carbonate platform. In: HAMPSON, G., DALRYMPLE, R. (Ed.). Recent advances in shoreline shelf Stratigraphy. Tulsa, Okla., 2008. (SEPM Special Issue n. 90).

Publication Dates

Publication in this collection
27 Aug 2010
Date of issue
2010

History

Reviewed
27 Nov 2009
Received
03 June 2009
Accepted
21 May 2010

This work is licensed under a Creative Commons Attribution 4.0 International License.

[1] ASHLEY, G. Classification of large-scale subaqueous bedforms: a new look at an old problem. J. sedim. Petrol, v. 60, p. 60-172, 1990.

[2] BOYD, R.; DALRYMPLE, R. W.; ZAITLIN, B. A. Estuarine and incised-valley facies models. In: POSAMENTIER, H. W.; WALKER, R. G. (Ed). Facies models revisited Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 84, p. 171-235).

[3] CALDAS, L. H. O.; STATTEGGER, K.; VITAL, H. Holocene sea-level history ; Evidence from coastal sediments of the northern Rio Grande do Norte coast, NE Brazil. Mar. Geol, v. 228, p. 39-53, 2006.

[4] CHAVES, M.; VITAL, H.; SILVEIRA, I. M. Beach morphodynamics of the Serra oil field, northeastern Brazil. J. coast. Res, Special Issue 39, p. 594-597. 2006.

[5] DALRYMPLE, R. W.; BOYD, R.; ZAITLIN, B. A. Incised-valley systems: Origin and sedimentary sequences. Tulsa, Okla.: 1994. (SEPM Spec. Publ., n. 51, p. 03-10).

[6] DALRYMPLE, R.W.; LECKIE, D. A.; TILLMAN, R.W. Incised valleys in time and space Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 85).

[7] LI, C.; WANG, P.; FAN, D.; YANG, S. Characteristics and formation of late Quaternary incised-valley-fill sequences in sediment-rich deltas and estuaries: case study from China. In: DALRYMPLE, R.W.; LECKIE, S. A.; TILLMAN, R.W. (Ed.). Incised valleys in time and space Tulsa, Okla., 2006. (SEPM Spec. Publ., n. 85, p. 141-160).

[8] LIMA, S. F.; VITAL, H. Geomorphological and paleogeographic characterization of continental shelf of the Apodi-Mossoró River, RN-Brazil. In: BREBBIA, C. A.. (Ed.). Environmental problems in coastal regions VI, including oil spill studies Cambridge, GB: Wessex Institute of Technology; Cambridge Printing, Great Britain, 2006. p. 351-360.

[9] LIMA, Z. M. C.; VITAL, H.; TABOSA, W.F. Morphodynamic Variability of The Galinhos Spit, Northeastern Brazil. J. coast Res, Special Issue, 39, p. 598-601, 2006.

[10] LORING, D. H.; RANTALA, R. T. T. Manual for the geochemical analysis of marine sediments and suspended particulate matter. Earth-Sci. Rev., v. 32, p. 235-283, 1992.

[11] MATOS, R. M. D. The northeastern Brazilian rift system. Tectonics, v. 1, p. 767 790, 1994.

[12] MILANI, E. J.; THOMAZ- FILHO, A. Sedimentary basins of South America. In: CORDANI, U. G.; MILANI, E. J.; THOMAZ- FILHO, A.; CAMPOS D. A. (Ed). Tectonic evolution of South america. INTERNATIONAL GEOLOGICAL CONGRESS. 31., Rio de Janeiro, 2000. p. 389-449.

[13] MITCHUM, R. M.; VAIL, P. R.; SANGREE, J. B. Seismic stratigraphy and global changes of sea level. Part 6: Stratigraphic interpretation of seismic reflection patterns in depositional sequences. In: PAYTON, C.E. (Ed.). Seismic Stratigraphy - application to hydrocarbon exploration. AAPG Memoir, n. 26, p. 117- 133, 1977.

[14] PELTIER, W. R. Global glacial isostatic adjustment and coastal tectonics. In: STEWART, I., VITA-FINZI, C. (Ed.). Coastal Tectonics. Geol. Soc. London, 1998. (Special Publ. n. 146, p. 1-29).

[15] PESSOA-NETO, O. C. Análise estratigráfica integrada da plataforma mista (Siliciclástica-Carbonática) do Neogeno da Bacia Potiguar, nordeste do Brasil 244 p. 1999. Dissertação (Mestrado) - Rio Grande do Sul Federal University, Porto Alegre-RS.

[16] PESSOA-NETO, O. C. Estratigrafia de Seqüências da Plataforma Mista Neogênicana Bacia Potiguar, Margem Equatorial Brasileira. Rev. Bras. Geociênc., v. . 33, p. 263-278, 2003.

[17] SANTOS, C. L. A.; VITAL, H.; AMARO, V. E.; KIKUCHY, R. K. P. Mapeamento de recifes na plataforma continental. Nordeste do Brasil: Touros a Maracajau RN. Brazilian J. Geoph, v. 1,p. 1-10, 2007.

[18] SCHWARZER, K.; STATTEGGER, K.; VITAL, H.; BECKER, M. Holocene coastal evolution of the Rio Açu Area (Rio Grande do Norte, Brazil). J. Coast Res, Special Issue n. 39, p. 141-145, 2006.

[19] STATTEGGER, K.; CALDAS, L. H. O.; VITAL, H. Holocene coastal evolution of the Northern Rio Grande do Norte Coast, Brazil. J. Coast. Res, Special Issue n. 39, p. 151-156, 2006.

[20] STEWART, I. S.; HANCOCK, P. L. What is a fault scarp? Episodes, v. 13-4, p. 256-263, 1990.

[21] TABOSA, W. F.; LIMA, Z. M. C.; VITAL, H.; GUEDES, I. M. G. Monitoramento costeiro das praias de São Bento do Norte e Caiçara do Norte NE Brasil. Rev. Pesq. Geoc, v. 28, p. 383-392, 2001.

[22] VITAL, H. Erosão e progradação no litoral do Rio Grande do Norte. In: MUEHE, D. (Org.). Erosão e progradação do litoral brasileiro. Brasilia, DF: Ministério do Meio Ambiente, p.159-176, 2005.

[23] VITAL, H.; STATTEGGER, K.; AMARO, V. E.; SCHWARZER, K.; FRAZÃO, E. P.; TABOSA, W. F. Inner continental shelf off northern Rio Grande do Norte, NE Brazil: A modern high-energy siliciclastic-carbonate platform. In: HAMPSON, G., DALRYMPLE, R. (Ed.). Recent advances in shoreline shelf Stratigraphy. Tulsa, Okla., 2008. (SEPM Special Issue n. 90).