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The Cocinetas Basin is located on the eastern flank of La Guajira Peninsula, northern Colombia (South Caribbean). During late Oligocene through Pliocene, much of the basin was submerged. The extensive deposits in this area suggest a transition from a shallow marine to a fluvio-deltaic system, with a rich record of invertebrate and vertebrate fauna. The elasmobranch assemblages of the early Miocene to late Pliocene succession in the Cocinetas Basin (Jimol, Castilletes and Ware Formations, and Patsúa Valley) are described for the first time. The assemblages include at least 30 taxa of sharks (Squaliformes, Pristiophoriformes, Orectolobiformes, Lamniformes and Carcharhiniformes) and batoids (Rhinopristiformes and Myliobatiformes), of which 24 taxa are reported from the Colombian Neogene for the first time. Paleoecological and paleoenvironmental interpretations are based on the feeding ecology, and on estimates of paleosalinity using stable isotope compositions of oxygen in the bioapatite of shark teeth. The isotopic composition of studied specimens corroborates the paleoenvironmental settings for the studied units suggested on the basis of other proxies. These Neogene elasmobranch assemblages from the Cocinetas Basin, provide new insights of the shark and ray diversity inhabiting the coastal and estuarine environments of the northwestern margin of South America, both during the existence of the gateway between the Atlantic and Pacific Oceans, and following its closure. [ABSTRACT FROM AUTHOR]

Copyright of Paläontologische Zeitschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Paläontologische Zeitschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Paläontologische Zeitschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Paläontologische Zeitschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An incomplete left hypoplastron of a trionychid turtle from the late Miocene-Early Pliocene Cubagua Formation of Margarita Island, Venezuela, represents the youngest occurrence of trionychids in South America. Large size and depositional environment of the Margarita Island specimen indicate marginal marine habits. The Neogene Venezuelan record is more extensive than previously considered and may represent an interval of successful colonization of the northern margin of South America by trionychids, as opposed to previous hypotheses of failed waif immigration. [ABSTRACT FROM AUTHOR]

Reports on the discovery of a coastal upwelling fish assemblage in the Caribbean Sea during the Neogene period. Physical and geologic setting; Composition of the fauna; Patterns of predator and prey relationships; Bathymetric range of taxa represented in the Miocene to early Pleistocene.

The Miocene Pirabas Formation is of strategic importance for the hydrocarbon industry since it represents the onshore portion of larger offshore basins of Northern Brazil, including the Foz de Amazonas, the Pará-Maranhão, Barreirinhas, Ceará, and the Potiguar basins of the equatorial margin of South America. The Pirabas Formation from the Aricuru outcrop (Pará State) is a shallow-water mixed siliciclastic-carbonate deposit, comprising highly bioturbated wackestone and packstone. However, the impact of these biogenic structures on the reservoir quality of this formation has been overlooked. Here, our results show that pervasive Thalassinoides penetrating the rock matrix, result in remarkably improved porosity and permeability, thus, turning the Pirabas Formation in extremely favorable strata for fluid flow and storage. Since these bioturbated layers are likely to be common in the sub-surface counterparts of this formation, the hydrocarbon potential of these deposits is probably higher than previously expected. Also, considering that the offshore basins of Northern Brazil are directly related to the breakup of the African and American plates during Aptian-Albian, the exploratory interest in the correlated Guinea Gulf (Jubilee play) and French Guiana-Suriname Basin (Zaedyus play) need to be reconsidered. Overall, the results of this research highlight the importance of integrating ichnological datasets with reservoir characterization studies for more accurate reservoir quality assessments. MicroCT of rock matrix plug sample and sectioned samples of Thalassinoides showing the calculate permo-porosity, and the digital model of inner flow through the burrow. Comparative dual permo-porosity from the Pirabas Formation and the relationship with referential reservoirs, Araújo, O., Aguilera, O., Coletti, G., Valencia, F.L., Buatois, L.A., Lopes, R. Marine and Petroleum Geology, Volume ..., Issue, ...(http://dx.doi.org/ ... .....). [Display omitted] • MicroCT analyses of rock matrix and ichnofossils provide high accuracy data on porosity and permeability. • Flow characteristics within the rock are reconstructed based on digitally MicroCT models. • Flow simulations range from laminar to turbulent and petrophysical properties from moderate to low. • Analysis of the Pirabas burrows may provide an appropriate experimental model for sub-surface reservoirs. [ABSTRACT FROM AUTHOR]

Outcrops of Neogene carbonates of the North Brazilian platform occur exclusively along the equatorial coast and represent some of the few existing examples of Neogene carbonate systems of the Atlantic coast of South America. The Pirabas Formation (early-middle Miocene) is the northernmost part of this platform. Although onshore mainly consists of small and scattered outcrops, it considerably extends in the subsurface keeping record of relevant geological and paleontological episodes of tropical South American history. Intending to improve the knowledge of South American carbonate and providing a solid basis for future comparisons between the Pirabas Basin and other, largely subsurface, Cenozoic basins, this research investigates the Aricuru outcrops by combining a standard petrographical and paleontological approach with advanced microCT analyses. The Aricuru area is characterized by mixed siliciclastic-carbonate sand-sized deposits, which probably deposited after the early Miocene according to the palynological assemblage. The bioclastic fraction of the rock is dominated by benthic foraminifera (mostly soritids, amphisteginids, small rotaliids, and small miliolids, typical of marginal marine environments), bryozoans, calcareous algae (Halimeda), echinoderms and mollusks. The abundant siliciclastic fraction together with the taxonomic composition of the foraminiferal, echinodermal, crustacean, ichnofossil and fish assemblages indicates deposition in a tropical coastal environment featuring both protected and more exposed sectors. The carbonate system probably developed under abundant nutrient supply, which fostered heterotroph suspension feeders over hermatypic corals. The demise of this system was most likely caused by a growth in siliciclastic input due to increased rainfall in the coastal area. The sedimentary evolution of the Pirabas Formation is similar to the one of the Foz do Amazonas Basin, and fits well with the general evolutionary trend of Cenozoic carbonate factories of the region, indicating the potential of the Pirabas subsurface record for understanding other Cenozoic basins, their paleoenvironmental significance, and their potential as oil, gas and water reservoirs. • The Pirabas Fm is a candidate for studying the global trends of carbonate factories • It is characterized by heterozoan carbonate factory from tropical shallow water coast • Coral carbonate producers were exclusively solitary corals • Increased supply of siliciclastic sediments caused the collapse of this system • The overall porosity could be higher than expected due to the complex ichnofabrics [ABSTRACT FROM AUTHOR]

The Pirabas Formation (early to middle Miocene) from the equatorial margin of North Brazil is characterized by a shallow-marine carbonate platform with high fossil diversity and abundant micro- and macrofossil remains. The Pirabas Formation represents a unique carbonate system along the Atlantic margin of South America that developed before the onset of the Amazon delta. We studied the palaeontology and lithofacies of outcrops of the uppermost Pirabas Formation and found that was deposited in a coastal marine environment with marginal lagoons under the influence of a tidal regime and tropical storms. The remains of calcareous algae, molluscs, crustaceans, echinoiderms, bryozoans, solitary corals, fish and marine mammals, together with foraminifera, ostracods and other marine microfossils, shaped a biogenic framework, that together with the post-depositional processes of dissolution of skeletal grains, is responsible for the mean packstone-floatstone porosity of 14.9%. The palaeontological framework and the petrophysical characterization of the carbonate rocks from the uppermost Pirabas Formation outcrop represent a baseline to interpret the entire Pirabas Formation in the subsurface stratigraphic sections (cores) of this important Neogene unit. Considering that carbonate rocks account for ~50% of oil and gas reservoirs around the world, this research provides a model for Neogene tropical carbonate deposits useful for carbonate petroliferous reservoirs in the Brazilian equatorial basins. • Microfossil assemblages suggest a middle Miocene age for the uppermost Pirabas Formation at the Atalaia outcrop. • The palaeoenvironment are characterized by coastal lagoons with mangrove forests and shallow inner platform. • Microfossil frameworks are responsible for the heterogeneity in the porosity values • The ultimate driver of the collapse of Pirabas carbonate production is still uncertaing • The Pirabas Formation could become a facies model for Neogene tropical carbonate deposits of the tropical Atlantic [ABSTRACT FROM AUTHOR]

Warmer temperatures and higher sea level than today characterized the Last Interglacial interval [Pleistocene, 128 to 116 thousand years ago (ka)]. This period is a remarkable deep-time analog for temperature and sea-level conditions as projected for 2100 AD, yet there has been no evidence of fossil assemblages in the equatorial Atlantic. Here, we report foraminifer, metazoan (mollusks, bony fish, bryozoans, decapods, and sharks among others), and plant communities of coastal tropical marine and mangrove affinities, dating precisely from a ca. 130 to 115 ka time interval near the Equator, at Kourou, in French Guiana. These communities include ca. 230 recent species, some being endangered today and/or first recorded as fossils. The hyperdiverse Kourou mollusk assemblage suggests stronger affinities between Guianese and Caribbean coastal waters by the Last Interglacial than today, questioning the structuring role of the Amazon Plume on tropical Western Atlantic communities at the time. Grassland-dominated pollen, phytoliths, and charcoals from younger deposits in the same sections attest to a marine retreat and dryer conditions during the onset of the last glacial (ca. 110 to 50 ka), with a savanna-dominated landscape and episodes of fire. Charcoals from the last millennia suggest human presence in a mosaic of modern-like continental habitats. Our results provide key information about the ecology and biogeography of pristine Pleistocene tropical coastal ecosystems, especially relevant regarding the-widely anthropogenic- ongoing global warming. [ABSTRACT FROM AUTHOR]

Pristine environmental conditions and wide biodiversity are the best evidence of pre-colonial times, before anthropic interference in the Anthropocene. The Galeão shell mound represents the main example of an insular archaeological site located in the context of the Guanabara Bay in the Middle Holocene. The faunal remains from this shell mound were identified through comparative anatomy, to access the ichthyofauna and also amphibian, reptile and mammal paleodiversity. The diagnostic elements revealed the presence of predominantly demersal teleost fish, typical inhabitants of estuarine and marine systems, along with the usual species inhabiting rocky shores and rocky bottoms. Additionally, it revealed an exceptional diversity of sharks, including the presence of pelagic taxa, as well as stingrays. The local wildlife consists of species commonly found in swampy, mangrove, Brazilian restinga and Atlantic forest biomes. This study shows widely practiced fishery and hunting by the Amerindian using the resources of the Guanabara Bay and indicates specific targets during the Middle Holocene. Degradation of coastal environments and/or overfishing threaten the local biodiversity, with species now absent and some with statuses which go from Vulnerable to Critically Endangered. [ABSTRACT FROM AUTHOR]

In this study, we describe and illustrate Pirabacarcinus iara n. gen. n. sp. , a novel species within the family Pilumnidae, collected from Miocene deposits of the Pirabas Formation, Brazil. Notably, this constitutes the first known fossil Pilumnidae from Brazil and only the second in South America, with the prior record from the Miocene of Chile. Pirabacarcinus iara n. gen. n. sp. is characterized by a series of distinct morphological characters, setting it apart from other known brachyuran species from the Pirabas Formation and other morphologically similar groups. The combination of a carapace with anterolateral margin longer than posterolateral margin, with three blunt spines anteriorly upturned; and a posterior region of carapace, including metabranchial and intestinal regions sloped, metabranchial region without lobes, and intestinal region reduced, faintly delimited set the new species apart from several brachyuran fossil genera. Opportunity is taken to describe and illustrate three cheliped fragments collected from the same locality of the new species. • Discovery of a new genus and species in Pirabas Formation enhances our knowledge of Brazilian Miocene crabs. • Pirabas Formation yields vital insights into brachyuran fossil evolution. • The description of this species marks the first known fossil Pilumnidae from Brazil and only the second in South America. [ABSTRACT FROM AUTHOR]

Worldwide, some of the largest hydrocarbon reservoirs are located in tropical neritic carbonate deposits. Biostratigraphic and paleoenvironmental analyzes of these sedimentary records are often based on the study of foraminiferal assemblage. Foraminifera-based biozones are widely employed in the oil industry to support drilling processes that, alongside petrophysical prospecting, define interval favorable for exploiting hydrocarbon resources. Both scientific research and the petroleum industry, however, usually apply traditional petrographical and paleontological methods to analyze microfossil assemblages, especially for large benthic foraminifera. New, faster, and more accurate methods based on microCT analyzes have emerged as a valuable high-output tool to obtain high-resolution microfossil records for biostratigraphy and paleoenvironmental reconstructions. This method is also useful for the development of digital databases for artificial intelligence applications. MicroCT analyzes, therefore, lead to faster identification of foraminifera assemblage and support digital access to international foraminifera repositories and reference collections, introducing a new dimension in micropaleontological research., Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study, performed during 2003-2005 and 2008-2009, investigated metals (Al, Fe, Ba, Zn, Mn, Cr, Cu, Ni, Cd) content in seston at Cabo Frio Bay, SE-Brazil. This study may serve as a baseline of seston metal distribution to guide biogeochemical and ecological models. The seston fractions (> 20 µm, > 64 µm, > 100 µm, and > 150 µm) were sampled in sub-surface horizontal hauls. Metals were determined by ICP-MS. The metals range: Al (62.5-56,867.6 µg g -1 ), Fe (23.5-25,384.0 µg g -1 ), Mn (2.7-336.8 µg g -1 ), Ba (< 0.005-356.3 µg g -1 ), Zn (0.5-94.2 µg g -1 ), Cr (0.7-35.5 µg g -1 ), Cu (4.3-41.7 µg g -1 ), Ni (< 0.005-19.1 µg g -1 ) and Cd (< 0.0004-2.4 µg g -1 ). Aluminium, Fe, Mn, Ba, and Zn showed significant differences (p < 0.05) between the seston fraction. The results obtained in this study suggest that the elements (Fe, Mn, Ba) in the seston were strongly influenced by the abiogenic source. In contrast, Zn, Cd, Cu, Cr, and Ni can be biogenic/anthropogenic sources. The significant positive linear correlation of Zn:P, Cd:P, and Cu:P can indicate an intracellular concentration higher than the external adsorption in the plankton community., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

The Sepetiba Bay (SB; SE Brazil) has been severely affected by growing of urbanization and industrial activity. This work aims to analyze the evolution of contamination by metals of sediments in SB. The results show a marked increasing trend in the concentrations of potentially toxic elements (PTEs), which is consistent with the rapid populational and industrial growth, mostly since 1970 CE. The remobilization and redistribution of sediments by currents have contributed to the dispersion of metals from the main source of pollutants to relatively distant regions. "Moderately to strongly polluted" sediments are also recorded in some sites in deeper sedimentary layers (namely in preindustrial periods), probably due to lithologic sources of the sediments. The concentrations of PTEs in SB are relatively high when compared with those found globally and in other Brazilian water bodies. Samples of high-resolution sediment cores confirmed that potential ecological risk to the coastal system is influenced not only through human actions but also by natural causes., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Mercury (Hg) is a toxic globally spread pollutant that has been found at increasing concentrations in the South Atlantic Ocean. The present work provides the first insight into the total mercury (HgT, unfiltered waters) content in the water of the Brazilian Exclusive Economic Zone (BEEZ), within a 24°S to 20°S. Water samples were collected from surface to 3400 m depth along transects, and analyzed with atomic fluorescence. The mean HgT concentration for the Tropical Water mass (TW) was 6.3 ± 1.4 pM (n = 16), for the South Atlantic Central Water (SACW), 5.9 ± 0.7 pM (n = 8), for the Antarctic Intermediate Water (AAIW), 5.0 ± 0.6 pM (n = 2), for the Upper Circumpolar Deep Water (UCDW), 6.5 pM (n = 1), and for the North Atlantic Deep Water (NADW), 5.7 ± 0.9 pM (n = 12). HgT concentrations were highest throughout the BEEZ in comparison with other parts of the Atlantic Ocean, farther from the coast., (Copyright © 2022 Elsevier Ltd. All rights reserved.)