The Alpha Crucis Carbonate Ridge (ACCR): Discovery of a giant ring-shaped carbonate complex on the SW Atlantic margin

Mascimiliano Maly; Uri Schattner; Francisco José Lobo; Rodolfo Jasão Soares Dias; Raissa Basti Ramos; Daniel de Matos Couto; Paulo Yukio Gomes Sumida; Michel Michaelovitch de Mahiques

doi:10.1038/s41598-019-55226-3

The Alpha Crucis Carbonate Ridge (ACCR): Discovery of a giant ring-shaped carbonate complex on the SW Atlantic margin

Mascimiliano Maly, Uri Schattner, Francisco José Lobo, Rodolfo Jasão Soares Dias, Raissa Basti Ramos, Daniel de Matos Couto, Paulo Yukio Gomes Sumida, Michel Michaelovitch de Mahiques

Department of Marine Geosciences

Research output: Contribution to journal › Article › peer-review

Abstract

Recently acquired bathymetric and high-resolution seismic data from the upper slope of Santos Basin, southern Brazilian margin, reveal a major geomorphological feature in the SW Atlantic that is interpreted as a carbonate ridge - the Alpha Crucis Carbonate Ridge (ACCR). The ACCR is the first megastructure of this type described on the SW Atlantic margin. The ~17 × 11-km-wide ring-shaped ACCR features tens of >100-m-high steep-sided carbonate mounds protruding from the surrounding seabed and flanked by elongated depressions. Comet-like marks downstream of the mound structures indicate that the area is presently influenced by the northward flow of the Intermediate Western Boundary Current (IWBC), a branch of the Subtropical Gyre that transports Antarctic Intermediate Water. Abundant carbonate sands and gravels cover the mounds and are overlain by a biologically significant community of living and dead ramified corals and associated invertebrates. The IWBC acts as a hydrodynamic factor that is responsible for both shaping the bottom and transporting coral larvae. We contend that the ACCR was formed by upward fluid flow along active sub-surface faults and fractures that formed by lateral extension generated by the ascending movement of salt diapirs at depth. The ACCR provides an important modern and accessible analogue for a seabed carbonate build-up related to sub-surface hydrocarbon systems.

Original language	English
Article number	18697
Journal	Scientific Reports
Volume	9
Issue number	1
DOIs	https://doi.org/10.1038/s41598-019-55226-3
State	Published - 1 Dec 2019

Bibliographical note

Funding Information:
The authors are indebted to the crew and researchers who participated in the Jan-Feb 2019 survey aboard the R.V. Alpha Crucis for their constant support. Acknowledgements are also due to the São Paulo Science Foundation (FAPESP grants 2014/08266-2, 2015/17763-2, and 2016/22194-0). MMdeM acknowledges the Brazilian National Research Council (CNPq, grant 300962/2018-5). The partnership between MMdeM and the US was supported by FAPESP (grant 2017/50191-8 – SPRINT Program). The partnership between MMdeM and F.J.L. was supported by CNPq (grant 401041/2014-0). The authors gratefully acknowledge support from Shell Brasil through the BIOIL project at the Oceanographic Institute of the University of São Paulo and the strategic importance of the support given by ANP through R&D levy regulation. We thank Petrel-Schlumberger for providing academic licenses that enabled the seismic interpretation.

Publisher Copyright:
© 2019, The Author(s).

ASJC Scopus subject areas

General

Access to Document

10.1038/s41598-019-55226-3

Cite this

@article{e418af81cc2048418658b03c28da6e4d,

title = "The Alpha Crucis Carbonate Ridge (ACCR): Discovery of a giant ring-shaped carbonate complex on the SW Atlantic margin",

abstract = "Recently acquired bathymetric and high-resolution seismic data from the upper slope of Santos Basin, southern Brazilian margin, reveal a major geomorphological feature in the SW Atlantic that is interpreted as a carbonate ridge - the Alpha Crucis Carbonate Ridge (ACCR). The ACCR is the first megastructure of this type described on the SW Atlantic margin. The ~17 × 11-km-wide ring-shaped ACCR features tens of >100-m-high steep-sided carbonate mounds protruding from the surrounding seabed and flanked by elongated depressions. Comet-like marks downstream of the mound structures indicate that the area is presently influenced by the northward flow of the Intermediate Western Boundary Current (IWBC), a branch of the Subtropical Gyre that transports Antarctic Intermediate Water. Abundant carbonate sands and gravels cover the mounds and are overlain by a biologically significant community of living and dead ramified corals and associated invertebrates. The IWBC acts as a hydrodynamic factor that is responsible for both shaping the bottom and transporting coral larvae. We contend that the ACCR was formed by upward fluid flow along active sub-surface faults and fractures that formed by lateral extension generated by the ascending movement of salt diapirs at depth. The ACCR provides an important modern and accessible analogue for a seabed carbonate build-up related to sub-surface hydrocarbon systems.",

author = "Mascimiliano Maly and Uri Schattner and Lobo, {Francisco Jos{\'e}} and Dias, {Rodolfo Jas{\~a}o Soares} and Ramos, {Raissa Basti} and Couto, {Daniel de Matos} and Sumida, {Paulo Yukio Gomes} and {de Mahiques}, {Michel Michaelovitch}",

note = "Funding Information: The authors are indebted to the crew and researchers who participated in the Jan-Feb 2019 survey aboard the R.V. Alpha Crucis for their constant support. Acknowledgements are also due to the S{\~a}o Paulo Science Foundation (FAPESP grants 2014/08266-2, 2015/17763-2, and 2016/22194-0). MMdeM acknowledges the Brazilian National Research Council (CNPq, grant 300962/2018-5). The partnership between MMdeM and the US was supported by FAPESP (grant 2017/50191-8 – SPRINT Program). The partnership between MMdeM and F.J.L. was supported by CNPq (grant 401041/2014-0). The authors gratefully acknowledge support from Shell Brasil through the BIOIL project at the Oceanographic Institute of the University of S{\~a}o Paulo and the strategic importance of the support given by ANP through R&D levy regulation. We thank Petrel-Schlumberger for providing academic licenses that enabled the seismic interpretation. Publisher Copyright: {\textcopyright} 2019, The Author(s).",

year = "2019",

month = dec,

day = "1",

doi = "10.1038/s41598-019-55226-3",

language = "English",

volume = "9",

journal = "Scientific Reports",

issn = "2045-2322",

publisher = "Nature Publishing Group",

number = "1",

}

TY - JOUR

T1 - The Alpha Crucis Carbonate Ridge (ACCR)

T2 - Discovery of a giant ring-shaped carbonate complex on the SW Atlantic margin

AU - Maly, Mascimiliano

AU - Schattner, Uri

AU - Lobo, Francisco José

AU - Dias, Rodolfo Jasão Soares

AU - Ramos, Raissa Basti

AU - Couto, Daniel de Matos

AU - Sumida, Paulo Yukio Gomes

AU - de Mahiques, Michel Michaelovitch

N1 - Funding Information: The authors are indebted to the crew and researchers who participated in the Jan-Feb 2019 survey aboard the R.V. Alpha Crucis for their constant support. Acknowledgements are also due to the São Paulo Science Foundation (FAPESP grants 2014/08266-2, 2015/17763-2, and 2016/22194-0). MMdeM acknowledges the Brazilian National Research Council (CNPq, grant 300962/2018-5). The partnership between MMdeM and the US was supported by FAPESP (grant 2017/50191-8 – SPRINT Program). The partnership between MMdeM and F.J.L. was supported by CNPq (grant 401041/2014-0). The authors gratefully acknowledge support from Shell Brasil through the BIOIL project at the Oceanographic Institute of the University of São Paulo and the strategic importance of the support given by ANP through R&D levy regulation. We thank Petrel-Schlumberger for providing academic licenses that enabled the seismic interpretation. Publisher Copyright: © 2019, The Author(s).

PY - 2019/12/1

Y1 - 2019/12/1

N2 - Recently acquired bathymetric and high-resolution seismic data from the upper slope of Santos Basin, southern Brazilian margin, reveal a major geomorphological feature in the SW Atlantic that is interpreted as a carbonate ridge - the Alpha Crucis Carbonate Ridge (ACCR). The ACCR is the first megastructure of this type described on the SW Atlantic margin. The ~17 × 11-km-wide ring-shaped ACCR features tens of >100-m-high steep-sided carbonate mounds protruding from the surrounding seabed and flanked by elongated depressions. Comet-like marks downstream of the mound structures indicate that the area is presently influenced by the northward flow of the Intermediate Western Boundary Current (IWBC), a branch of the Subtropical Gyre that transports Antarctic Intermediate Water. Abundant carbonate sands and gravels cover the mounds and are overlain by a biologically significant community of living and dead ramified corals and associated invertebrates. The IWBC acts as a hydrodynamic factor that is responsible for both shaping the bottom and transporting coral larvae. We contend that the ACCR was formed by upward fluid flow along active sub-surface faults and fractures that formed by lateral extension generated by the ascending movement of salt diapirs at depth. The ACCR provides an important modern and accessible analogue for a seabed carbonate build-up related to sub-surface hydrocarbon systems.

AB - Recently acquired bathymetric and high-resolution seismic data from the upper slope of Santos Basin, southern Brazilian margin, reveal a major geomorphological feature in the SW Atlantic that is interpreted as a carbonate ridge - the Alpha Crucis Carbonate Ridge (ACCR). The ACCR is the first megastructure of this type described on the SW Atlantic margin. The ~17 × 11-km-wide ring-shaped ACCR features tens of >100-m-high steep-sided carbonate mounds protruding from the surrounding seabed and flanked by elongated depressions. Comet-like marks downstream of the mound structures indicate that the area is presently influenced by the northward flow of the Intermediate Western Boundary Current (IWBC), a branch of the Subtropical Gyre that transports Antarctic Intermediate Water. Abundant carbonate sands and gravels cover the mounds and are overlain by a biologically significant community of living and dead ramified corals and associated invertebrates. The IWBC acts as a hydrodynamic factor that is responsible for both shaping the bottom and transporting coral larvae. We contend that the ACCR was formed by upward fluid flow along active sub-surface faults and fractures that formed by lateral extension generated by the ascending movement of salt diapirs at depth. The ACCR provides an important modern and accessible analogue for a seabed carbonate build-up related to sub-surface hydrocarbon systems.

UR - http://www.scopus.com/inward/record.url?scp=85076317064&partnerID=8YFLogxK

U2 - 10.1038/s41598-019-55226-3

DO - 10.1038/s41598-019-55226-3

M3 - Article

C2 - 31822741

AN - SCOPUS:85076317064

VL - 9

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 18697

ER -

The Alpha Crucis Carbonate Ridge (ACCR): Discovery of a giant ring-shaped carbonate complex on the SW Atlantic margin

Abstract

Bibliographical note

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this