Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil

Formed during marine regression periods, shelf valleys (SVs) are preterit river flows on the exposed continental shelf. This study investigates the influence of tectonic activity on forming these important morphological features. This research combines bathymetric, magnetometry, and seismic data to...

Full description

Saved in:
Bibliographic Details
Main Authors: Luis Felipe de Melo Tassinari, Tereza Cristina Medeiros de Araújo, José Antônio Barbosa
Format: Article
Language:English
Published: Instituto Oceanográfico da Universidade de São Paulo 2024-04-01
Series:Ocean and Coastal Research
Subjects:
Online Access:https://journals.usp.br/ocr/article/view/222858
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849714136147034112
author Luis Felipe de Melo Tassinari
Tereza Cristina Medeiros de Araújo
José Antônio Barbosa
author_facet Luis Felipe de Melo Tassinari
Tereza Cristina Medeiros de Araújo
José Antônio Barbosa
author_sort Luis Felipe de Melo Tassinari
collection DOAJ
description Formed during marine regression periods, shelf valleys (SVs) are preterit river flows on the exposed continental shelf. This study investigates the influence of tectonic activity on forming these important morphological features. This research combines bathymetric, magnetometry, and seismic data to analyze the role of tectonic events in SV genesis and positioning. The bathymetric dataset provides information on SV locations and geometries along the continental shelf, whereas the 2D seismic sections illustrate that SVs formed above post-rift faults that reached Quaternary deposits. Aeromagnetic data indicates that the shallow and deep structures of the basement and sedimentary column controlled SV locations and evolution. The multi-data integration demonstrates a strong correlation between neotectonic structures and SV location and geometries from the inner shelf (−25 m) to the shelf break (−55 m). The analysis of the 2D seismic data indicated that high-angle faults, formed under a strikeslip tectonic regime, primarily affected the Middle Miocene deposits beneath the shelf valleys. The formation of “negative flower pattern structures” was identified as a primary structural mechanism that contributed to SV formation. Reactivation events that occurred from the Late Cretaceous onwards, gave rise to these faults, which control SV formation and the capture of preterit drainage on the exposed continental shelf. The SV geometries display straight patterns and abrupt changes in direction (90°) due to the interplay of the NE-SW and NW-SE aligned faults. The results reinforce the importance of considering tectonic activity in the formation and evolution of shelf valleys.
format Article
id doaj-art-eefd5de31cbf43f18621caf75e2c3984
institution DOAJ
issn 2675-2824
language English
publishDate 2024-04-01
publisher Instituto Oceanográfico da Universidade de São Paulo
record_format Article
series Ocean and Coastal Research
spelling doaj-art-eefd5de31cbf43f18621caf75e2c39842025-08-20T03:13:47ZengInstituto Oceanográfico da Universidade de São PauloOcean and Coastal Research2675-28242024-04-017210.1590/2675-2824072.22151Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - BrazilLuis Felipe de Melo TassinariTereza Cristina Medeiros de AraújoJosé Antônio Barbosa Formed during marine regression periods, shelf valleys (SVs) are preterit river flows on the exposed continental shelf. This study investigates the influence of tectonic activity on forming these important morphological features. This research combines bathymetric, magnetometry, and seismic data to analyze the role of tectonic events in SV genesis and positioning. The bathymetric dataset provides information on SV locations and geometries along the continental shelf, whereas the 2D seismic sections illustrate that SVs formed above post-rift faults that reached Quaternary deposits. Aeromagnetic data indicates that the shallow and deep structures of the basement and sedimentary column controlled SV locations and evolution. The multi-data integration demonstrates a strong correlation between neotectonic structures and SV location and geometries from the inner shelf (−25 m) to the shelf break (−55 m). The analysis of the 2D seismic data indicated that high-angle faults, formed under a strikeslip tectonic regime, primarily affected the Middle Miocene deposits beneath the shelf valleys. The formation of “negative flower pattern structures” was identified as a primary structural mechanism that contributed to SV formation. Reactivation events that occurred from the Late Cretaceous onwards, gave rise to these faults, which control SV formation and the capture of preterit drainage on the exposed continental shelf. The SV geometries display straight patterns and abrupt changes in direction (90°) due to the interplay of the NE-SW and NW-SE aligned faults. The results reinforce the importance of considering tectonic activity in the formation and evolution of shelf valleys. https://journals.usp.br/ocr/article/view/222858Shelf ValleysGeophysicsMiddle MioceneHigh Angle FaultsNeotectonics
spellingShingle Luis Felipe de Melo Tassinari
Tereza Cristina Medeiros de Araújo
José Antônio Barbosa
Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
Ocean and Coastal Research
Shelf Valleys
Geophysics
Middle Miocene
High Angle Faults
Neotectonics
title Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
title_full Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
title_fullStr Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
title_full_unstemmed Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
title_short Neotectonic control of shelf valley formation on the southern Pernambuco continental shelf - Brazil
title_sort neotectonic control of shelf valley formation on the southern pernambuco continental shelf brazil
topic Shelf Valleys
Geophysics
Middle Miocene
High Angle Faults
Neotectonics
url https://journals.usp.br/ocr/article/view/222858
work_keys_str_mv AT luisfelipedemelotassinari neotectoniccontrolofshelfvalleyformationonthesouthernpernambucocontinentalshelfbrazil
AT terezacristinamedeirosdearaujo neotectoniccontrolofshelfvalleyformationonthesouthernpernambucocontinentalshelfbrazil
AT joseantoniobarbosa neotectoniccontrolofshelfvalleyformationonthesouthernpernambucocontinentalshelfbrazil