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Journal Article

Decompositional processes of microbial carbonates in Lagoa Vermelha, Brazil Available to Purchase

Fumito Shiraishi, Yusaku Hanzawa, Jiro Asada, Leonardo Fadel Cury, Anelize Manuela Bahniuk
Published: 30 March 2023
Journal of Sedimentary Research (2023) 93 (3): 202–211.
DOI: https://doi.org/10.2110/jsr.2022.053
...Fumito Shiraishi; Yusaku Hanzawa; Jiro Asada; Leonardo Fadel Cury; Anelize Manuela Bahniuk ABSTRACT In Lagoa Vermelha, Brazil, a lagoonal stromatolite and a saltpan microbial mat are investigated to understand the influence of environmental changes on the decomposition of microbial carbonates...
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View PDF for article title, Decompositional processes of microbial carbonates in <span class="search-highlight">Lagoa</span> <span class="search-highlight">Vermelha</span>, Brazil
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Journal Article

Sedimentological and geochemical characterization of microbial mats from Lagoa Vermelha (Rio de Janeiro, Brazil) Available to Purchase

Caio Bittencourt Guedes, Michele Correia Arena, Hélisson Nascimento dos Santos, Bruno Valle, Jeferson de Andrade Santos, Julia Favoreto, Leonardo Borghi
Published: 30 June 2022
Journal of Sedimentary Research (2022) 92 (6): 591–600.
DOI: https://doi.org/10.2110/jsr.2021.072
..., and geomicrobiology of these microbialites. This paper, however, focuses on the petrography, sedimentology, and geochemistry of recent and superficial microbial mats from Lagoa Vermelha to understand the interaction of carbonate and siliciclastic grains with an organic matrix and discuss their similarities...
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View PDF for article title, Sedimentological and geochemical characterization of microbial mats from <span class="search-highlight">Lagoa</span> <span class="search-highlight">Vermelha</span> (Rio de Janeiro, Brazil)
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Journal Article

Microstructure and mineral composition of Holocene stromatolites from Lagoa Vermelha, a hypersaline lagoon in Brazil: Insights into laminae genesis Available to Purchase

Carolina N. Keim, Hélisson Nascimento dos Santos, Carolina Souza Santiago, Simone Pennafirme, Reiner Neumann, Jürgen Schnellrath, Inayá Lima, Mirian A.C. Crapez, Marcos Farina
Published: 27 August 2020
Journal of Sedimentary Research (2020) 90 (8): 887–905.
DOI: https://doi.org/10.2110/jsr.2020.40
... remains controversial, and a convincing explanation for how stromatolites arise from microbial mats is still lacking. In this work, we analyze in detail a stromatolite from Lagoa Vermelha, a coastal hypersaline lagoon in Rio de Janeiro State, Brazil. The stromatolite presents a laminated core...
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View PDF for article title, Microstructure and mineral composition of Holocene stromatolites from <span class="search-highlight">Lagoa</span> <span class="search-highlight">Vermelha</span>, a hypersaline lagoon in Brazil: Insights into laminae genesis
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Journal Article

Microbial mediation of modern dolomite precipitation and diagenesis under anoxic conditions (Lagoa Vermelha, Rio de Janeiro, Brazil) Available to Purchase

Crisogono Vasconcelos, Judith A. McKenzie
Published: 01 May 1997
Journal of Sedimentary Research (1997) 67 (3): 378–390.
DOI: https://doi.org/10.1306/D4268577-2B26-11D7-8648000102C1865D
... in Lagoa Vermelha, a shallow-water isolated coastal lagoon east of Rio de Janeiro, Brazil, provides a new environment to investigate the factors promoting dolomite precipitation under earth surface conditions. Lagoa Vermelha serves as a natural laboratory in which the dolomite formation process was studied...
View PDF for article title, Microbial mediation of modern dolomite precipitation and diagenesis under anoxic conditions (<span class="search-highlight">Lagoa</span> <span class="search-highlight">Vermelha</span>, Rio de Janeiro, Brazil)
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Sampling location at the Vermelha Lagoon. A) Detail map of Lagoa Vermelha showing the E7 sampling site. B) Photo of polygonal mat collected at E7 site. C, D) Transversal cut showing inner laminae and color zonation of the microbial mat collected.

Sampling location at the Vermelha Lagoon. A) Detail map of Lagoa Vermelha... Available to Purchase

Published: 05 April 2021
Fig. 2.— Sampling location at the Vermelha Lagoon. A) Detail map of Lagoa Vermelha showing the E7 sampling site. B) Photo of polygonal mat collected at E7 site. C , D) Transversal cut showing inner laminae and color zonation of the microbial mat collected.
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An overview of the study sites. A) Location of Lagoa Vermelha, Brazil. B) Setting of Lagoa Vermelha, divided into three parts. C) Sampling sites of this study. At the sampled saltpan, evaporitic condensation proceeds from west to east. D) Stromatolites develop in the eastern part. Many of them are eroded to the water surface level, except for some submerged smaller ones (arrows). E) Submerged domal stromatolite. F) Saltpan around the sampling site. Carbonate and gypsum dominate the left side ponds, while gypsum and halite dominate the right side ponds. G) Cross section of a deposit developed in the pond precipitating carbonate and gypsum. A thick, orange microbial mat is developed. H) Cross section of a deposit developed in the pond precipitating gypsum and halite. The deposit lacks a thick microbial mat and is rather whitish.

An overview of the study sites. A) Location of Lagoa Vermelha, Brazil. B... Available to Purchase

Published: 30 March 2023
Fig. 1 An overview of the study sites. A) Location of Lagoa Vermelha, Brazil. B) Setting of Lagoa Vermelha, divided into three parts. C) Sampling sites of this study. At the sampled saltpan, evaporitic condensation proceeds from west to east. D) Stromatolites develop in the eastern part
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Location map of Lagoa Vermelha, Rio de Janeiro State. A detailed satellite image shows the geomorphology of Lagoa Vermelha and the sampled location (red circle) (Google Earth 2020).

Location map of Lagoa Vermelha, Rio de Janeiro State. A detailed satellite ... Available to Purchase

Published: 30 June 2022
Fig. 1.— Location map of Lagoa Vermelha, Rio de Janeiro State. A detailed satellite image shows the geomorphology of Lagoa Vermelha and the sampled location (red circle) (Google Earth 2020).
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Map showing the location of Lagoa Vermelha on the southeastern coast of the state of Rio de Janeiro, Brazil.

Map showing the location of Lagoa Vermelha on the southeastern coast of the... Available to Purchase

Published: 05 April 2021
Fig. 1.— Map showing the location of Lagoa Vermelha on the southeastern coast of the state of Rio de Janeiro, Brazil.
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Maps and photographs of the study area. A–C) Maps showing Lagoa Vermelha. A) Brazilian coast showing the location of Lagoa Vermelha (arrow), close to Rio de Janeiro city. B) A series of coastal lagoons lies along Rio de Janeiro State coast. The box encloses Lagoa Vermelha. C) Detailed map of Lagoa Vermelha. Divisions of the lagoon are artificial and were done for salt extraction. Asterisks point to sites of sample collection. D–G) Photographs of Lagoa Vermelha and the stromatolites. D–E) Images obtained at the south margin on October 2015 (asterisk at the left in Part C; coordinates –22.932851, –42.393020). D) Overview of the south margin showing several stromatolites in shallow areas. E) Stromatolites collected close to the south margin. F–G) East margin on October 2014, (asterisk at the right in Part C; coordinates –22.926357, –42.369443). F) Overview showing some stromatolite heads uncovered by water in an exceptionally dry year. G) Close-up of three contiguous stromatolite heads. Note dry microbial mats lying on marginal sediments showing the characteristic polygonal crack pattern at the bottom of the picture.

Maps and photographs of the study area. A–C) Maps showing Lagoa Vermelha. ... Available to Purchase

Published: 27 August 2020
Fig. 1.— Maps and photographs of the study area. A–C) Maps showing Lagoa Vermelha. A) Brazilian coast showing the location of Lagoa Vermelha (arrow), close to Rio de Janeiro city. B) A series of coastal lagoons lies along Rio de Janeiro State coast. The box encloses Lagoa Vermelha. C
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Hypothesis for stromatolite growth in Lagoa Vermelha microbial mats. As photosynthetic microorganisms migrate upwards towards light, they are followed by microorganisms from underlying layers, as well as by physical and chemical gradients, which results in net growth of the microbial mat upwards, whereas minerals and organic debris are left behind. The explanations below refer to minerals illustrated at the bottom of each panel. They follow the sequence of mineral precipitation in distinct microenvironments in the microbial mat, until they form one consolidated lamina. Upper layers illustrate upward growth as well as previous steps in laminae genesis. Time increments left to right. Minerals are shown in grayscale, and living cells in colors. A) Elongated particles of aragonite precipitated chemically from water and were deposited on microbial mat upper surfaces. Aragonite was favored due to the high Mg:Ca ratio of lagoon water, which inhibits calcite growth. Seasonal variations caused the periodic pattern of aragonite. B) Upward growth of oxygenic phototrophs (cyanobacteria and/or algae) leads to microbial mat growth and incorporation of the aragonite particles. The pH increase resulting from oxygenic photosynthesis results in the precipitation of an amorphous Mg-SiOx phase, possibly on dead organic remains. This step could result in aragonite–Mg-SiOx composite peloids. C) Organic-matter degradation generates large amounts of DIC and lower pH, leading to replacement of the Mg-SiOx phase by (V)HMC, largely maintaining the peloidal morphology. The high Mg content arises from Mg-SiOx dissolution, whereas Ca2+ ions come from EPS degradation and/or lagoon water. Aragonite is not likely a source of Ca2+ ions because they show little evidence of dissolution. The result is aragonite–(V)HMC peloids. D) Further degradation of organic matter, releasing DIC and also Ca2+ and Mg2+ ions from EPS, leads to precipitation of HMC cements, binding the peloids together, and generating consolidated laminae. Until this step, organic matter filled most spaces between laminae. E) Shrinking of organic matter between consolidated laminae due to degradation enabled small organisms with shells such as foraminifera, ostracods, and even small mollusks to reach the spaces between laminae. F) After they die, their shells remain in the voids, and later precipitation of a HMC fringe cements them to lamina surfaces. Organic matter in the voids is further degraded and/or washed out, leaving empty spaces between peloidal laminae. G) Details of the possible mechanism for Mg-silicate replacement by (V)HMC, illustrated in Part C. Organic matter (mainly EPS) degradation in microbial mats releases bound Ca2+ ions and CO2. CO2 combines with water forming HCO3–, CO32–, and H+. Decreased pH, increased DIC and Ca2+, as well as matching of short-range ordered regions of Mg-silicate and (V)HMC (template effect) leads to replacement of the Mg-silicate phase by (V)HMC, largely maintaining the peloidal morphology. For (V)HMC precipitation, Ca2+ and CO32–come largely from EPS degradation, whereas Mg2+ comes mainly from Mg-silicate dissolution. Silicate ions are lost in the process. CH2O illustrates organic matter, and some chemical reactions are unbalanced for clarity.

Hypothesis for stromatolite growth in Lagoa Vermelha microbial mats. As pho... Available to Purchase

Published: 27 August 2020
Fig. 12.— Hypothesis for stromatolite growth in Lagoa Vermelha microbial mats. As photosynthetic microorganisms migrate upwards towards light, they are followed by microorganisms from underlying layers, as well as by physical and chemical gradients, which results in net growth of the microbial
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Porewater and sediment geochemistry from Lagoa Vermelha, Brazil. A: SO42–, HS–, and dissolved inorganic carbon (DIC). Conc.—concentration. B: Mg2+ and Ca2+. C: pH. D: Calculated saturation indices (SI) for aragonite, calcite, and dolomite. IAP—ion activity product. E: δ13C values of bulk carbonate and DIC. VPDB—Vienna Peedee belemnite.

Porewater and sediment geochemistry from Lagoa Vermelha, Brazil. A: SO 4 2... Available to Purchase

Published: 01 April 2013
Figure 2. Porewater and sediment geochemistry from Lagoa Vermelha, Brazil. A: SO 4 2– , HS – , and dissolved inorganic carbon (DIC). Conc.—concentration. B: Mg 2+ and Ca 2+ . C: pH. D: Calculated saturation indices (SI) for aragonite, calcite, and dolomite. IAP—ion activity product. E: δ 13 C
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Aspects of a recent microbial mat (Lagoa Vermelha, Brazil) from samples without acid treatment in natural conditions (Parts A–C) and after an experimental diagenesis, e.g., exposed to anoxia without light for three years (Parts D–F): A) TEM image of algae with a thick cell wall and lipidic inclusions (white arrow). B) SEM image of microbes composed of coccoid (black arrow) and filamentous bacteria (white arrow) associated with carbonates. C) 3D-AFM image of two filaments (grey arrow) covered by nanometer-scale spheroids (black arrows). D) TEM image of microbial degradation characterized by remains of cell walls (white arrow) and nanometer-scale spheroids showing an external dark membrane (black arrows). E) SEM image of nanometer-scale spheroids (white arrows) associated with EPS. F) TEM image of dark nanometer-scale spheroids (white arrow) associated with bacterial cell wall.

Aspects of a recent microbial mat (Lagoa Vermelha, Brazil) from samples wit... Available to Purchase

Published: 01 October 2010
Figure 4 Aspects of a recent microbial mat (Lagoa Vermelha, Brazil) from samples without acid treatment in natural conditions (Parts A–C) and after an experimental diagenesis, e.g., exposed to anoxia without light for three years (Parts D–F): A) TEM image of algae with a thick cell wall
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TABLE 1. CHEMICAL COMPOSITION OF LAGOA VERMELHA (LV) AND DESULFONATRONUM L... Available to Purchase

Published: 01 December 2006
TABLE 1. CHEMICAL COMPOSITION OF LAGOA VERMELHA (LV) AND DESULFONATRONUM LACUSTRE CULTURE MEDIA
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Figure 4. Dolomite sample from upper few centimeters of Lagoa Vermelha sediment. Scanning electron microscope photomicrograph shows dumbbell and cauliflower shapes similar to those observed in pure cultures of sulfate-reducing bacteria strain LVform6, which was isolated from Lagoa Vermelha sediment.

Figure 4. Dolomite sample from upper few centimeters of Lagoa Vermelha sedi... Available to Purchase

Published: 01 December 2000
Figure 4. Dolomite sample from upper few centimeters of Lagoa Vermelha sediment. Scanning electron microscope photomicrograph shows dumbbell and cauliflower shapes similar to those observed in pure cultures of sulfate-reducing bacteria strain LVform6, which was isolated from Lagoa Vermelha sediment.
Journal Article

Bacterially induced dolomite precipitation in anoxic culture experiments Available to Purchase

Rolf Warthmann, Yvonne van Lith, Crisógono Vasconcelos, Judith A. McKenzie, Anne Marie Karpoff
Journal: Geology
Published: 01 December 2000
Geology (2000) 28 (12): 1091–1094.
DOI: https://doi.org/10.1130/0091-7613(2000)28<1091:BIDPIA>2.0.CO;2
...Figure 4. Dolomite sample from upper few centimeters of Lagoa Vermelha sediment. Scanning electron microscope photomicrograph shows dumbbell and cauliflower shapes similar to those observed in pure cultures of sulfate-reducing bacteria strain LVform6, which was isolated from Lagoa Vermelha sediment. ...
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Figure 5. Surface- and pore-water \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \({\delta}^{18}O_{SO_{4}}\) \end{document} vs. \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \({\delta}^{34}S_{SO_{4}}\) \end{document} values. Star—seawater (SW); solid circles—pore-water samples; X—Lagoa Araruama surface brine; gray square—Brejo do Espinho surface brine; open square— Lagoa Vermelha seaward-side surface brine; triangle—Lagoa Vermelha continental-side surface brine. See text for discussion. SMOW—standard mean ocean water; CDT—Cañon Diablo troilite.

Figure 5. Surface- and pore-water \batchmode \documentclass[fleqn,10pt,le... Available to Purchase

Published: 01 August 2004
— Lagoa Vermelha seaward-side surface brine; triangle—Lagoa Vermelha continental-side surface brine. See text for discussion. SMOW—standard mean ocean water; CDT—Cañon Diablo troilite.
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TABLE 1. COMPOSITION OF LV CULTURE MEDIUM VS. SEASONAL RANGES IS LAGOA VERM... Available to Purchase

Published: 01 December 2000
TABLE 1. COMPOSITION OF LV CULTURE MEDIUM VS. SEASONAL RANGES IS LAGOA VERMELHA
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Figure 3. Chloride concentrations of surface brines and pore waters in study lagoons. Surface brines are indicated by square symbols. Lagoa Vermelha brines are likely sourced from seawater and meteoric water, while Brejo do Espinho brines are sourced from seawater and Lagoa Araruama brine. SW—seawater; contl—continental.

Figure 3. Chloride concentrations of surface brines and pore waters in stud... Available to Purchase

Published: 01 August 2004
Figure 3. Chloride concentrations of surface brines and pore waters in study lagoons. Surface brines are indicated by square symbols. Lagoa Vermelha brines are likely sourced from seawater and meteoric water, while Brejo do Espinho brines are sourced from seawater and Lagoa Araruama brine. SW
Journal Article

Role of sulfide oxidation in dolomitization: Sediment and pore-water geochemistry of a modern hypersaline lagoon system Available to Purchase

Naila F. Moreira, Lynn M. Walter, Crisogono Vasconcelos, Judith A. McKenzie, Patti J. McCall
Journal: Geology
Published: 01 August 2004
Geology (2004) 32 (8): 701–704.
DOI: https://doi.org/10.1130/G20353.1
...— Lagoa Vermelha seaward-side surface brine; triangle—Lagoa Vermelha continental-side surface brine. See text for discussion. SMOW—standard mean ocean water; CDT—Cañon Diablo troilite. ...
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Schematic sketch representing the lagoons and sandy barriers of Região dos Lagos region. 1) Precambrian basement, 2) Pre-Flandrian sandy deposits, 3) lagoon deposits and inner lagoon, 4) external sandy barrier, 5) external lagoons (Lagoa Vermelha), 6) Post-Flandrian barriers (modified from Coe Neto 1984).

Schematic sketch representing the lagoons and sandy barriers of Região dos ... Available to Purchase

Published: 30 June 2022
Fig. 2.— Schematic sketch representing the lagoons and sandy barriers of Região dos Lagos region. 1) Precambrian basement, 2) Pre-Flandrian sandy deposits, 3) lagoon deposits and inner lagoon, 4) external sandy barrier, 5) external lagoons (Lagoa Vermelha), 6) Post-Flandrian barriers (modified