| 1. |
- Amano, Kazutaka, et al.
(författare)
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Bivalvia in ancient hydrocarbon seeps
- 2022
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Ingår i: Ancient Hydrocarbon Seeps. - Berlin : Springer Berlin/Heidelberg. ; , s. 267-321
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Bokkapitel (refereegranskat)abstract
- Bivalves are an important part of the methane seep fauna ever since seeps appeared in the geologic record. The chronostratigraphic ranges of seep-inhabiting chemosymbiotic bivalves show an overall increase in diversity at seeps since the Paleozoic. The most common group at Paleozoic and early Mesozoic seeps are modiomorphids, with a few additional records of solemyids and anomalodesmatans. The most common infaunal chemosymbiotic bivalve taxa at modern seeps, lucinids and thyasirids, appeared at seeps in the Late Jurassic and earliest Cretaceous. They diversified during the Cretaceous synchronous with the peak of the “Mesozoic Marine Revolution” and first occurrences of gastropod predatory drill holes in the shells of seep-inhabiting bivalves, soon after the appearance of these gastropods in the mid-Cretaceous. The two dominant bivalve clades of the modern vent and seep fauna, bathymodiolins and vesicomyids, appeared in the Eocene. Their origin has been linked to a deep-water extinction event at the Paleocene-Eocene Thermal Maximum. However, the fossil record of chemosymbiotic bivalves at seeps during this time interval does not display any extinction. Rather, the mid-Eocene appearance of semi-infaunal and epifaunal bivalves such as bathymodiolins and vesicomyids might be linked to a dramatic rise in seawater sulfate concentrations at this time.
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| 2. |
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| 3. |
- Ceballos, Yasmani, et al.
(författare)
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Corals and mollusks from a Miocene carbonate-rich deposit of Madruga, western Cuba
- 2021
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Ingår i: Poeyana. - Havana : Cuban Academy of Sciences. - 2410-7492. ; 512, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Here is reported fauna from a Middle Miocene limestone deposit of the Cojímar Formation near the town of Aguacate in the Province of Mayabeque, western Cuba. The fossils are preserved only as internal or external molds, but we identified members of at least eight bivalves and six gastropod families and one solitary coral. The most common taxon is a lucinid bivalve probably belonging to the genus Anodontia, which may likely represent a new taxon. This species in particular, and the fauna and facies in general, suggest that the Aguacate limestone may represent an ancient seagrass meadow environment. The fauna of the Aguacate quarry shows biogeographic relationships mainly to the Miocene of Panama and Florida, but also some links to the subtropical Atlantic coast of North America, and the Miocene of northern Ecuador.
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| 4. |
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| 5. |
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| 6. |
- Goedert, James L., et al.
(författare)
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Miocene Nautilus (Mollusca, Cephalopoda) from Taiwan, and a review of the Indo‐Pacific fossil record of Nautilus
- 2022
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Ingår i: Island Arc. - Hoboken : John Wiley & Sons. - 1038-4871 .- 1440-1738. ; 31:1
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Tidskriftsartikel (refereegranskat)abstract
- The fossil record of the cephalopod genus Nautilus has been obscured because a few influential taxonomists during the 20th Century decided that fossils similar to Nautilus were instead other genera. We now recognize fossils once classified as species of other genera as species of Nautilus. This includes fossils from Miocene rocks of Taiwan that were previously described as Kummelonautilus taiwanum but herein recognized instead as being the northernmost Neogene record of Nautilus in the Indo-Pacific region. The name is corrected to Nautilus taiwanus, and now known to occur in two formations in central Taiwan, the early Miocene Shihmentsun and early to middle Miocene Houdongkeng formations. Miocene fossils from Indonesia that were placed in other genera are now considered to represent Nautilus as they were originally assigned, in addition to several Miocene species from Australia, which provide the southernmost Neogene fossil record for the genus. Some of these Indo-Pacific fossils may represent the same species, but more specimens are needed to determine the amount of variability within these Neogene taxa.
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| 7. |
- Goedert, James L., et al.
(författare)
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Octocorals (Alcyonacea and Pennatulacea) from Paleogene deep-water strata in western Washington State, USA
- 2022
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Ingår i: Journal of Paleontology. - Washington DC : Paleontological Society (United States). - 0022-3360 .- 1937-2337. ; 96:3, s. 539-551
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Tidskriftsartikel (refereegranskat)abstract
- The fossil record of octocorals from Cenozoic marine strata of western North America is quite limited, and they have not been reported previously from rocks in Washington State, USA. Two late Oligocene specimens from the upper part of the Lincoln Creek Formation in western Washington, referred to Radicipes? sp., are the first fossil record of the family Chrysogorgiidae. The family Isididae is represented by an internode and two holdfasts identified as Isidella sp. collected from the Oligocene Pysht Formation, along with specimens questionably identified as Lepidisis sp., possibly the first fossil record for this genus. Together, these are the first confirmed fossils of the Alcyonacea from north of California in western North America. The axes of sea pens from several late Eocene or early Oligocene localities in the Lincoln Creek Formation in the central part of western Washington, and the Pysht and Makah formations on the north side of the Olympic Peninsula, are the first fossil record for the Pennatulacea from western North America; all are tentatively referred to the genus ‘Graphularia’. Large axes from the Lincoln Creek Formation and Makah Formation are referred to ‘Graphularia’ (?) aff. sasai, because they are similar to the species known only from late Eocene and early Oligocene rocks in Japan.
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| 8. |
- Guan, Hongxiang, et al.
(författare)
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Lipid Biomarker Patterns Reflect Nutritional Strategies of Seep-Dwelling Bivalves From the South China Sea
- 2022
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Ingår i: Frontiers in Marine Science. - Lausanne : Frontiers Media. - 2296-7745. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Invertebrates living at methane seeps such as mussels and clams gain nutrition through symbiosis with chemosynthetic, chiefly methanotrophic and thiotrophic bacteria. Lipid biomarkers, including their compound-specific carbon stable isotope compositions, extracted from the host tissues are predestined for deciphering the various sources of diets and the associations among varying environments, endosymbionts, and hosts. Here, we investigated lipid inventories of soft tissues of two bathymodiolin mussel species hosting aerobic methanotrophic bacteria (Gigantidas platifrons from Site F and Gigantidas haimaensis from Haima seeps), one bathymodiolin mussel with thiotrophic bacteria (Bathymodiolus aduloides from Haima seeps), and one vesicomyid clam (Archivesica marissinica from Haima seeps) from the South China Sea. The gills of mussels hosting methanotrophic symbionts were found to contain high amounts of lipids of aerobic methanotrophic bacteria, such as the 4,4-dimethyl lanosterol, and other 4-methyl sterols, and the type I methanotroph-specific monounsaturated fatty acids (MUFAs) C16:1ω9 and C16:1ω8. Production of methyl-sterols is favored over fatty acids at low oxygen concentrations, as demonstrated in culture experiments with Methylococcus capsulatus. Since lesser fatty acids and abundant sterols are found in G. haimaensis compared to G. platifrons, G. haimaensis apparently lived at very low oxygen levels. Extremely high levels of MUFAs C16:1ω7 and C18:1ω7 were found in gill tissue of both B. aduloides and the vesicomyid clam A. marissinica. Given the absence of ω8 fatty acids, both B. aduloides and the vesicomyid clam contain thiotrophic bacteria only. The occurrence of 13C-enriched 24-methylenecholesterol in B. aduloides indicates that the animal complemented its diet by filter-feeding (ca. 3% of the total sterol inventory) on photosynthetically derived carbon, whereas the majority of sterols are pointing to a diet relying on endosymbionts. Different types of 4-methyl sterols were observed between the thiotroph-containing mussel and methanotroph-containing mussels, suggesting different biosynthetic steps are present from lanosterol to cholesterol between animal hosts and aerobic methanotrophs. Among the four bivalve species, specific lipid biomarker patterns diagnostic for either the symbionts or the hosts yielded similar δ13C values in each species, indicating that the host obtained its nutrition either directly from the symbionts or derived at least most of its carbon in this way. The information derived from lipid biomarkers of bivalves and their corresponding symbionts in modern environments is vital to interpret data from the rock record, where most other methods to study microbial community composition are not applicable.
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| 9. |
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| 10. |
- Hryniewicz, Krzysztof, et al.
(författare)
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Thyasirid bivalves from Cretaceous and Paleogene cold seeps
- 2017
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Ingår i: Acta Palaeontologica Polonica. - Warsaw : Instytut Paleobiologii PAN. - 0567-7920 .- 1732-2421. ; 62:4, s. 705-728
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Tidskriftsartikel (refereegranskat)abstract
- We present a systematic study of thyasirid bivalves from Cretaceous to Oligocene seep carbonates worldwide. Eleven species of thyasirid bivalves are identified belonging to three genera: Conchocele, Maorithyas, and Thyasira. Two species are new: Maorithyas humptulipsensis sp. nov. from middle Eocene seep carbonates in the Humptulips Formation, Washington State, USA, and Conchocele kiritachiensis sp. nov. from the late Eocene seep deposit at Kiritachi, Hokkaido, Japan. Two new combinations are provided: Conchocele townsendi (White, 1890) from Maastrichtian strata of the James Ross Basin, Antarctica, and Maorithyas folgeri (Wagner and Schilling, 1923) from Oligocene rocks from California, USA. Three species are left in open nomenclature. We show that thyasirids have Mesozoic origins and appear at seeps before appearing in “normal” marine environments. These data are interpreted as a record of seep origination of thyasirids, and their subsequent dispersal to non-seep environments. We discuss the age of origination of thyasirids in the context of the origin of the modern deep sea fauna and conclude that thyasirids could have deep sea origins. This hypothesis is supported by the observed lack of influence of the Cretaceous and Paleogene Oceanic Anoxic Events on the main evolutionary lineages of the thyasirids, as seen in several other members of the deep sea fauna.
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| 11. |
- Hybertsen, Frida, 1988-, et al.
(författare)
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A middle Eocene seep deposit with silicified fauna from the Humptulips Formation in western Washington State, USA
- 2018
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Ingår i: Acta Palaeontologica Polonica. - Warsaw : Instytut Paleobiologii PAN. - 0567-7920 .- 1732-2421. ; 63:4, s. 751-768
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Tidskriftsartikel (refereegranskat)abstract
- Carbonate blocks with silicified fossils were recovered from a newly recognized cold seep deposit, the Satsop Weatherwax site, in the basal Humptulips Formation, along the West Fork of Satsop River in Washington State, USA. The petrography and the stable carbon isotope signature of the carbonate, with values as low as -43.5‰, indicate that these carbonate blocks formed at an ancient methane seep. The fossils recovered from this block include five vesicomyid specimens, two fragments of a thyasirid, five specimens of the peltospirid Depressigyra, two specimens of the hyalogyrinid Hyalogyrina, 25 specimens of the neritimorph Thalassonerita eocenica, and three limpet specimens of two different species. Five species can be described as new: Nuculana acutilineata (Nuculanoidea), Desbruyeresia belliatus (Provannidae), Provanna fortis (Provannidae), Orbitestella dioi (Orbitestellidae), and Leptochiton terryiverseni (Polyplacophora). Other fossils recovered from this site are numerous serpulid tubes, echinoid spines, one brachiopod fragment and two neogastropods. Almost all species recovered belong to extant genera and the fauna has a modern character, but are different from species found in younger seeps in Washington State. This is the first record of an orbitestellid from an ancient cold seep deposit, the first fossil provannids from the Humptulips Formation, and the first fossil record of Desbruyeresia from North America.
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| 12. |
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| 13. |
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| 14. |
- Hybertsen, Frida, 1988-
(författare)
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Systematics and assessment of the chemosynthetic bivalve family Vesicomyidae
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The deep ocean has fascinated researchers for centuries with discoveries of new ecosystems and species, yet there are still many biogeographic and evolutionary questions unanswered. Along active and passive tectonic margins, specialized ecologies thrive in a symbiosis between chemosynthesizing bacteria and their host animals. This specialized fauna exists in particular in areas where hydrocarbon seepage occurs. Hydrocarbon seep environments have been of research interest since their discovery in the Gulf of Mexico in 1984. They are home to a diverse chemosynthetic fauna whose fossil record extends back to the Paleozoic. This project strives to increase the understanding of the biodiversity, biogeography and evolution of seeps and their diverse fauna. It is focused around the Cenozoic seep fauna, and especially the bivalve family Vesicomyidae that have dominated chemosynthetic systems since the late Eocene. The taxonomy of this family is under revision; discrepancy between molecular and morphological characteristics has resulted in cryptic species. To help improve the taxonomic and evolutionary framework, the main focus of the PhD project is to create a phylogeny based on the combination of morphological data and molecular data, with including most of the fossil vesicomyid species. Vesicomyid literature and specimens from museum collections have been thoroughly examined and analyzed using cladistics to assess their taxonomy and evolution. Stratigraphic dispersal of vesicomyids is recorded in a stratophenic comparison to visualize first occurrences and early species radiation, providing an overview of their fossil record and compiling the appearance of evolutionary traits. Reassessment of taxonomic groupings lead to the description of the new genus Squiresica, which includes the small-sized Arhicvesica knapptonensis and Archivesica marincovichi. Furthermore, from the Humptulips Formation in northwestern USA and the Talara Basin in northern Peru, we describe four new seep sites. Hydrocarbon seep sites in Italy, Cuba and Taiwan are examined for a biostratigraphic purpose. From USA and Peru, 11 new seep-mollusk species are identified and the fossil content from all locations are indicative of a modern type seep fauna. The phylogenetic analysis reveals that several morphology-based groupings correspond well to molecular groups, and that climate may have played a role in the shell size difference we see in fossils around the Eocene-Oligocene transition.
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| 15. |
- Ivanova, Varvara V., et al.
(författare)
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Sediment geochemistry of the section Tagay-1 at Olkhon Island (Lake Baikal, Eastern Siberia): a contribution to palaeoenvironmental interpretations
- 2022
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Ingår i: Palaeobiodiversity and Palaeoenvironments. - : Springer. - 1867-1594 .- 1867-1608. ; 102:4, s. 921-941
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Tidskriftsartikel (refereegranskat)abstract
- The Miocene Tagay section in the north-western part of Olkhon Island, Lake Baikal, provides a unique window into past life in northern Asia. To aid palaeoenvironmental reconstructions, we carried out whole-rock geochemical analyses of 17 sedimentary layers of this section. The aim of this geochemical approach is to examine the element variations as a response to climate change during formation of the Tagay section deposits with a focus on the hydrological regime of the catchment and in-lake processes. Our results establish that temperature and climate conditions during the formation of sediments of section Tagay-1 were fairly stable, no abrupt climatic changes occurred. The palaeoclimate was temperate, however, it had a cyclic nature: wet and semiarid epochs of different intensity and duration alternated. The basal part of the sediment sequence is dominated by terrigeneous material, mainly by surface runoff, so the sedimentation was fed by erosion products of the weathering crust. During sedimentation of this lower part (layers 17–9), the palaeo-lake level and salinity stayed practically unchanged. The drawdown of the palaeo-lake and increasing salinity started in the higher middle part (layer 8), and reached the minimum water level and maximum salinity in layers 7–6. Sediments of the layers 8–6 accumulated in an arid climate. After deposition of layer 5, the water level began to rise, and during formation of layer 3 it fell again. The highest sedimentation rate was in layers 12–5, these are also the layers with the highest enrichment of biogenic elements (layers 12, 7–5) and where carbonate deposition took place. The observed changes in element behaviour are related to hydrological changes in the catchment (precipitation), lake level status, and evaporation, and are ultimately driven by climate.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
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| 21. |
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| 22. |
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| 23. |
- Kiel, Steffen, et al.
(författare)
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A thyasirid-dominated methane-seep deposit from Montañita, southwestern Ecuador, from the Oligocene-Miocene boundary
- 2021
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Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology. - Amsterdam : Elsevier. - 0031-0182 .- 1872-616X. ; 575
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Tidskriftsartikel (refereegranskat)abstract
- A mass occurrence of the thyasirid bivalve Thyasira montanita in a limestone bed, exposed at Punta Montañita on the northern side of the Santa Elena peninsula in southeastern Ecuador, is here identified as an ancient methane-seep deposit. The massive to nodular limestone shows carbonate phases and microfabrics typical of seep limestones, such as banded and botryoidal cements. Its δ13 Ccarbonate values, as low as −52.6‰, suggest a biogenic methane source. Furthermore, the carbonate microfabrics and biomarkers typical of ANME-2 archaea indicate high seepage rates. Tubular fossils previously interpreted as worm tubes show cone-shaped projections and an internal structure consistent with that of crustacean cuticle and are here interpreted as crustacean fragments. Seep deposits with mass occurrences of thyasirid bivalves have so far only been reported from the Cretaceous, making the Montañita seep deposit the first such example from the Cenozoic. The faunal and biomarker inventories of this deposit indicate deposition on an open shelf; the oysters on the upper surface of the limestone are likely secondary encrusters that arrived only after the emergence of this deposit in shallower water.
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| 24. |
- Kiel, Steffen, et al.
(författare)
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Cenozoic methane-seep faunas of the Caribbean region
- 2015
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:10
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Tidskriftsartikel (refereegranskat)abstract
- We report new examples of Cenozoic cold-seep communities from Colombia, Cuba, the Dominican Republic, Trinidad, and Venezuela, and attempt to improve the stratigraphic dating of Cenozoic Caribbean seep communities using strontium isotope stratigraphy. Two seep faunas are distinguished in Barbados: the late Eocene mudstone-hosted ‘Joes River fauna’ consists mainly of large lucinid bivalves and tall abyssochrysoid gastropods, and the early Miocene carbonate-hosted ‘Bath Cliffs fauna’ containing the vesicomyid Pleurophopsis, the mytilid Bathymodiolus and small gastropods. Two new Oligocene seep communities from the Sinú River basin in Colombia consist of lucinid bivalves including Elongatolucina, thyasirid and solemyid bivalves, and Pleurophopsis. A new early Miocene seep community from Cuba includes Pleurophopsis and the large lucinid Meganodontia. Strontium isotope stratigraphy suggests an Eocene age for the Cuban Elmira asphalt mine seep community, making it the oldest in the Caribbean region. A new basal Pliocene seep fauna from the Dominican Republic is characterized by the large lucinid Anodontia (Pegophysema). In Trinidad we distinguish two types of seep faunas: the mudstone-hosted Godineau River fauna consisting mainly of lucinid bivalves, and the limestone-hosted Freeman’s Bay fauna consisting chiefly of Pleurophopsis, Bathymodiolus, and small gastropods; they are all dated as late Miocene. Four new seep communities of Oligocene to Miocene age are reported from Venezuela. They consist mainly of large globular lucinid bivalves including Meganodontia, and moderately sized vesicomyid bivalves. After the late Miocene many large and typical ‘Cenozoic’ lucinid genera disappeared from the Caribbean seeps and are today known only from the central Indo-Pacific Ocean. We speculate that the increasingly oligotrophic conditions in the Caribbean Sea after the closure of the Isthmus of Panama in the Pliocene may have been unfavorable for such large lucinids because they are only facultative chemosymbiotic and need to derive a significant proportion of their nutrition from suspended organic matter.
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| 25. |
- Kiel, Steffen, et al.
(författare)
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Chemosymbiotic bivalves from Miocene methane-seep carbonates in Italy
- 2017
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Ingår i: Journal of Paleontology. - Cambridge : Cambridge University Press. - 0022-3360 .- 1937-2337. ; 91, s. 444-466
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Tidskriftsartikel (refereegranskat)abstract
- Eleven species of chemosymbiotic bivalves are reported from middle to late Miocene methane seep deposits (‘Calcari a Lucina’) in the Italian Apennines, including seven new species and one new genus. The new species are Bathymodiolus (s.l.) moroniae and B. (s.l.) miomediterraneus among the Bathymodiolinae and Archivesica aharoni, A. apenninica, A. strigarum, and ‘Pliocardia’ italica among the Vesicomyidae; specimens from the middle Miocene of Deruta are reported as Archivesica aff. aharoni. Samiolus iohannesbaptistae new genus new species is introduced for an unusual mytilid with a commarginally ribbed surface, which might be the first non-bathymodiolin mytilid obligate to the seep environment. The two large lucinid species from which these deposits derived their informal name ‘Calcari a Lucina’ are identified as Meganodontia hoernea (Des Moulins, 1868) and Lucinoma perusina (Sacco, 1901). With Chanellaxinus sp., we report the first thyasirid from a Neogene deep-water seep deposit in Italy and the first fossil occurrence of this genus.
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| 26. |
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| 27. |
- Kiel, Steffen, et al.
(författare)
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Fossiliferous methane-seep deposits from the Cenozoic Talara Basin in northern Peru
- 2020
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Ingår i: Lethaia. - : Scandinavian University Press / Universitetsforlaget AS. - 0024-1164 .- 1502-3931. ; 53:2, s. 166-182
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Tidskriftsartikel (refereegranskat)abstract
- Thirteen fossiliferous limestone deposits from Cenozoic strata in the Talara Basin in northern Peru are identified as ancient methane-seep deposits. Planktonic foraminifera and the existing stratigraphical framework of the Talara Basin indicate an early Oligocene, or possibly late Eocene, age of these deposits. They are found in three distinct areas - Belen, Cerro La Salina and Cerros El Pelado - and differ in their petrography, stable isotope signatures, and lipid biomarker and macrofaunal contents. At Belen, the carbon stable isotope signature of the carbonate and the abundance of n-alkanes indicates the possibility of oil seepage in addition to methane seepage; for Belen and Cerro La Salina the high abundance of the biomarker crocetane indicates a dominance of anaerobic methane-oxidizing archaea of the ANME-2 group, whereas the rather small combined crocetane/phytane peak of a Cerros El Pelado limestone agrees with mixed ANME-1/ANME-2 input. The macrofauna consists mainly of molluscs; the Cerro La Salina sites include mostly infaunal thyasirid and lucinid bivalves and only few vesicomyid bivalves; gastropods include Provanna antiqua, the limpet Pyropelta and several vetigastropods. The Belen site is dominated by the elongate vesicomyid bivalve Pleurophopsis lithophagoides. The most common bivalve at the Cerros El Pelado sites is an undetermined, possible vesicomyid, and a smooth provannid gastropod. Biogeographically the faunas are most similar to those of the northwestern United States, as indicated by two joint species; similarities on the genus level (Conchocele, Lucinoma, Pleurophopsis, Provanna, Colus) exist also with Japan and the Caribbean region.
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| 28. |
- Kiel, Steffen, et al.
(författare)
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Late Triassic mollusk-dominated hydrocarbon-seep deposits from Turkey
- 2017
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Ingår i: Geology. - Boulder : Geological Society of America. - 0091-7613 .- 1943-2682. ; 44, s. 751-754
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Tidskriftsartikel (refereegranskat)abstract
- Deep-sea hydrothermal vents and hydrocarbon seeps host unique ecosystems relying on geochemical energy rather than photosynthesis. Whereas the fossil and evolutionary history of these ecosystems is increasingly well known from the Cretaceous onward, their earlier history remains poorly understood and brachiopods are considered to have played a dominant role during the Paleozoic and Mesozoic. Here we report five new hydrocarbon-seep deposits from the Upper Triassic Kasımlar shales in southern Turkey. The pyritiferous seep limestones predominantly consist of 13C-depleted micrite with δ13C values as low as −10.4‰, and contain only sparse 13C-depleted rim cement (δ13C as low as −12.0‰), interpreted to result from the recrystallization of banded and botryoidal crystal aggregates of fibrous cement. The geologic ages of the studied seep deposits were determined as late Carnian and early Norian using conodonts. The associated fauna is dominated by modiomorphid and anomalodesmatan bivalves, and also includes a diversity of gastropods and the dimerelloid brachiopod Halorella. These faunal assemblages allow a comparison between seep faunas from the two major Triassic ocean basins—the present assemblages being from Tethys, and the only previously known examples being from eastern Panthalassa—and indicate that a cosmopolitan, seep-restricted fauna as in the present-day oceans has existed since the Late Triassic. With almost 20 species, the seep fauna of the Kasımlar shales approaches the diversity of Cretaceous to present-day seep faunas, further emphasizing the ecological similarity of seep faunas since the early Mesozoic. Our findings also highlight that brachiopods and bivalves had a more complex history of coexistence at seeps than currently appreciated.
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| 29. |
- Kiel, Steffen, et al.
(författare)
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Mollusks and a crustacean from early Oligocene methane-seep deposits in the Talara Basin, northern Peru
- 2020
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Ingår i: Acta Palaeontologica Polonica. - : Polska Akademia Nauk Instytut Paleobiologii (Institute of Paleobiology, Polish Academy of Sciences). - 0567-7920 .- 1732-2421. ; 65:1, s. 109-138
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Tidskriftsartikel (refereegranskat)abstract
- A total of 25 species of mollusks and crustaceans are reported from Oligocene seep deposits in the Talara Basin in northern Peru. Among these, 12 are identified to the species-level, including one new genus, six new species, and three new combinations. Pseudophopsis is introduced for medium-sized, elongate-oval kalenterid bivalves with a strong hinge plate and largely reduced hinge teeth, rough surface sculpture and lacking a pallial sinus. The new species include two bivalves, three gastropods, and one decapod crustacean: the protobranch bivalve Neilo altamirano and the vesicomyid bivalve Pleurophopsis talarensis; among the gastropods, the pyropeltid Pyropelta seca, the provannid Provanna pelada, and the hokkaidoconchid Ascheria salina; the new crustacean is the callianassid Eucalliax capsulasetaea. New combinations include the bivalves Conchocele tessaria, Lucinoma zapotalensis, and Pseudophopsis peruviana. Two species are shared with late Eocene to Oligocene seep faunas in Washington state, USA: Provanna antiqua and Colus sekiuensis; the Talara Basin fauna shares only genera, but no species with Oligocene seep fauna in other regions. Further noteworthy aspects of the molluscan fauna include the remarkable diversity of four limpet species, the oldest record of the cocculinid Coccopigya, and the youngest record of the largely seep-restricted genus Ascheria. Eucalliax is recorded for the first time from a seep and from the Oligocene.
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| 30. |
- Kiel, Steffen, et al.
(författare)
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Mollusks from Miocene hydrocarbon-seep deposits in the Ilocos-Central Luzon Basin, Luzon Island, Philippines
- 2022
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Ingår i: Acta Palaeontologica Polonica. - Warsaw : Instytut Paleobiologii PAN. - 0567-7920 .- 1732-2421. ; 67:4, s. 917-947
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Tidskriftsartikel (refereegranskat)abstract
- We report 35 molluscan species from Late Miocene cold-seep carbonates from the Amlang Formation in the Ilocos- Central Luzon Basin in Luzon Island, Philippines, collected in a large quarry in the province of Pangasinan. The 19 bivalve species are largely representatives of chemosymbiotic families; the six new species are the nuculid Acila (Truncacila) interferencia sp. nov., the mytilid Bathymodiolus labayugensis sp. nov., the thyasirid Conchocele pangasinanensis sp. nov., the lucinid Megaxinus gorrospei sp. nov., the vesicomyid Pliocardia ballesterosi sp. nov., and Sisonia frijellanae gen. et sp. nov., of uncertain taxonomic affinity. The 16 gastropods include one species restricted to seep deposits, the neritid species Thalassonerita hagai sp. nov.; the buccinid Enigmaticolus semisulcata represents the first fossil record of its genus. Biogeographically, the Pangasinan seep fauna shows several links to Neogene seep faunas in other tropical/subtropical areas, namely the Mediterranean and Caribbean regions. In contrast, shared taxa with nearby but extratropical Japan are few, as are shared taxa with Miocene seep deposits in New Zealand.
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| 31. |
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| 32. |
- Kiel, Steffen, et al.
(författare)
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New taxa, records, and data for vesicomyid bivalves from Cenozoic strata of the North Pacific region
- 2023
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Ingår i: Acta Palaeontologica Polonica. - 0567-7920 .- 1732-2421. ; 68:2, s. 297-320
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Tidskriftsartikel (refereegranskat)abstract
- New discoveries of Cenozoic deep-water hydrocarbon seep deposits and continued collecting at previously documented sites in the North Pacific region have resulted in additional fossils of vesicomyid bivalves and necessitate a systematic review. We report five new vesicomyid species, including four species from western Washington State, USA: Isorropodon humptulipsense sp. nov. from middle to upper Eocene strata of the Humptulips Formation and the “Siltstone of unit B”, the oldest record for Isorropodon, Pleurophopsis thieli sp. nov. from upper Eocene to lowermost Oligocene strata of the Lincoln Creek, Makah, and Pysht formations, and Pliocardia? guthrieorum sp. nov. and Squiresica plana sp. nov. from Oligocene strata of the Lincoln Creek and Pysht formations. The new species Squiresica yooni sp. nov. is from the Middle Miocene Duho Formation in South Korea. We report possibly the as-yet oldest Vesicomya from a lower Oligocene seep deposit in the Lincoln Creek Formation in western Washington. Pliocardia kawadai was previously only known from Lower to Middle Miocene strata in Japan; with our new record from the Lower to Middle Miocene Astoria Formation in western Washington, this species represents the first fossil vesicomyid species with a trans-Pacific distribution. The large and elongated Pleurophopsis chinookensis is restricted to upper Eocene strata; previous Oligocene records are shown to belong to other species.
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| 33. |
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| 34. |
- Kiel, Steffen
(författare)
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Reply to Smith et al.: Network analysis reveals connectivity patterns in the continuum of reducing ecosystems
- 2017
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - London : The Royal Society Publishing. - 0962-8452 .- 1471-2954. ; 284
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Tidskriftsartikel (refereegranskat)abstract
- The role of whale falls in the connectivity among, and adaptation to, reducing ecosystems in the deep sea has been the matter of a long debate. Hydrothermal vents are the most extreme among the reducing habitats in terms of temperature, metal concentrations and in their geographical isolation, and it is hence thought that stepping stones are needed to reach them. As new types of reducing habitats are being discovered, they are now increasingly seen as a ‘continuum of reducing ecosystems’. Taking this concept seriously implies that any habitat type within this continuum could provide connectivity to any other. Thus rather than focusing just on whales, I will address the issues raised by Smith et al. in the context of the question ‘who provides connectivity with whom, and to which extent?’
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| 35. |
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| 36. |
- Kiel, Steffen, et al.
(författare)
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The late Cenozoic evolution of the Humboldt Current System in coastal Peru: Insights from neodymium isotopes
- 2023
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Ingår i: Gondwana Research. - : Elsevier. - 1342-937X .- 1878-0571. ; 116, s. 104-112
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Tidskriftsartikel (refereegranskat)abstract
- The Humboldt Current System along the Pacific coast of South America creates one of the most productive ecosystems on Earth. To trace the origin of the water masses in this area, we measured neodymium isotope compositions (ԑNd) in tooth enameloid of two genera of coastal sharks from latest Oligocene to early Pleistocene strata in the Pisco and Sacaco basins in southern Peru. Most ԑNd values range from −4 to −1, with a strong negative excursion in the late Miocene (∼8–7 million years ago [Ma]) with values as low as −9.2. The overall trend of the ԑNd values resembles that of equatorial Pacific deep waters, though with an offset of about +2 ԑNd units until about 6 Ma. With a major input of hinterland weathering considered unlikely, we interpret this pattern as reflecting a modern-type upwelling regime, though with a lower contribution of Antarctic waters than today. Starting about 6 Ma, the contribution of Antarctic waters to the upwelling waters increased approximately to present-day levels, coincident with, and possibly driven by, increased Antarctic glaciation and the Andes reaching their present-day elevation, both of which likely enhanced the counter-clockwise circulation in the South Pacific Ocean. The negative excursion of ԑNd values in the Pisco/Sacaco basins ∼8–7 Ma coincides with a late Miocene biogenic bloom in the Pacific Ocean and elsewhere, and with a strongly increased northward bottom current observed on the Nazca Drift System just offshore our sampling area. Thus, the negative excursion of ԑNd values in the Pisco/Sacaco basins likely resulted from a southern sourced input of nutrient-rich, unradiogenic water, which could have been an important contributor to the biogenic bloom.
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| 37. |
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| 38. |
- Kiel, Steffen, et al.
(författare)
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Unusual Miocene hydrocarbon-seep faunas from the Brisighella area in northern Italy: embedded in clastics and first records of the lucinid bivalves Megaxinus and Miltha
- 2023
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Ingår i: Acta Palaeontologica Polonica. - : Instytut Paleobiologii PAN. - 0567-7920 .- 1732-2421. ; 68:1, s. 127-132
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Tidskriftsartikel (refereegranskat)abstract
- Ancient hydrocarbon-seep sites known as “Calcari a Lucina” are common in Miocene strata of northern Italy and typically consist of carbonate deposits dominated by large lucinid, bathymodiolin, and vesicomyid bivalves. Here we report two new sites found in Upper Miocene strata at Monte Mauro near Brisighella in the Emilia-Romagna province. One is unusual by being embedded in unconsolidated siltstone without any carbonate, but yet, consisting of the typical, seep-restricted bivalves Bathymodiolus moroniae and Archivesica aharoni vesicomyid clams and bathymodiolin mussels. The second deposit is dominated by the lucinid Megaxinus bellardianus, which has never been reported from a Miocene seep deposit in this region, despite being common in coeval siliciclastic sediments nearby. This species emphasizes biogeographic relationships between Upper Miocene seep faunas in the Mediterranean region and the tropic Indo-West Pacific Ocean.
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| 39. |
- Kiel, Steffen
(författare)
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Using network analysis to trace the evolution of biogeography through geologic time: A case study
- 2017
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Ingår i: Geology. - Boulder : Geological Society of America. - 0091-7613 .- 1943-2682. ; 45, s. 711-714
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Tidskriftsartikel (refereegranskat)abstract
- The biogeographic distribution of organisms has continuously changed through Earth’shistory as plate tectonics changed the configurations of land masses, ocean basins, and climatezones. Yet, methods to investigate this dynamic through geologic time are limited. Here,network analysis is used to explore and to visualize the biogeographic history of brachiopodsthrough the entire Triassic period. Many previously recognized biogeographic provinces arefound, and in addition, the stratigraphic ranges of these provinces were identified. Provincesin the Tethys Ocean show the lowest degree of connectedness, which can be linked to higherevolutionary rates in this tropical ocean basin and possibly also to higher habitat heterogeneity.Stratigraphically, the Tethyan provinces are separated largely along the boundaries ofthe Early, Middle, and Late Triassic. This suggests that the events resulting in faunal changesamong the index fossils used to define these sub-periods also affected the brachiopods. However,through the ~50 m.y. of the Triassic period, geographic proximity played a greater rolein producing faunal similarity than proximity in geologic age. Thus network analysis is aviable tool to better understand the dynamic evolution of biogeography through geologic time.
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| 40. |
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| 41. |
- Liebenau, Katharina, et al.
(författare)
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A quantitative study on the degradation of whale bone lipids: implications for the preservation of fatty acids in marine sediments
- 2015
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Ingår i: Organic Geochemistry. - : Elsevier BV. - 0146-6380 .- 1873-5290. ; 89-90, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- The degradation and preservation affecting the biomarker record of ancient metazoa are not fully 33understood. We report on a five month experiment on the fate of fatty acids (FAs) during the degradation 34of recent whale vertebrae (Phocoena phocoena). Whale bones were analysed for extractable FAs and 35macromolecularly bound n-acyl compounds. Fresh bone showed extractable FAs dominated by 3616:1x7c, 16:0, 18:1x9c and 18:0. Calculated degradation rate constant (k) values showed a rapid 37decrease in FA concentration, with k values higher for unsaturated than for saturated compounds 38(e.g. 0.08/day for 18:1x9c, 0.05/day for 16:0). The appearance or increased abundance of distinctive 39methyl branched (e.g. i/ai-15:0 and -17:0, 10Me-16:0) and hydroxy FAs (e.g. 10OH-16:0 and 10OH- 4018:0) were observed, providing clear evidence for the microbial degradation of bone organic matter 41and an input of lipids from specialised bacteria. Catalytic hydropyrolysis (HyPy) of demineralised extrac- 42tion residues released up to 0.13% of the total n-C16 and n-C18 moieties in the degraded bones. This 43revealed that only a small, yet sizeable portion of bone-derived fatty acyl units was sequestered into 44(proto)kerogen during the earliest stages of degradation.
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| 42. |
- Müller, Sandro P, et al.
(författare)
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Mass occurrence of echinoids in an Oligocene hydrocarbon-seep limestone from the Olympic Peninsula, Washington State, USA
- 2023
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Ingår i: Geological Magazine. - Cambridge : Cambridge University Press. - 0016-7568 .- 1469-5081. ; 160:5, s. 941-954
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Tidskriftsartikel (refereegranskat)abstract
- Loose limestone blocks of a newly recognized hydrocarbon-seep deposit from the lower Oligocene Jansen Creek Member of the Makah Formation were collected on a beach terrace close to the mouth of Bullman Creek in Washington State, USA. The limestone consists largely of authigenic carbonate phases, including 13C-depleted fibrous cement forming banded and botryoidal crystal aggregates with δ13C values as low as –23.5 ‰. Lipids extracted from the limestone yielded molecular fossils of anaerobic methanotrophic archaea (ANME), dominated by compounds of an ANME-2/DSS consortium with δ13C values as low as −106 ‰, indicating formation at an ancient methane seep. The fossil inventory of the seep deposit is remarkable, consisting almost solely of echinoid remains, whereas typical seep biota are absent. Varying preservation of the echinoid fossils indicates parautochthonous deposition, corroborated by evidence for high fluid flow at the ancient seep, possibly responsible for displacement of echinoids after death. Although a full taxonomic description of the echinoids cannot be given, almost all fossils were assigned to one taxon of irregular spatangoids, except for a single regular echinoid. Abundance and lifestyle of the irregular spatangoids in the Bullman Creek echinoid seep deposit resemble those of the fossil Tithonia oxfordiana from an upper Jurassic seep deposit in France and extant Sarsiaster griegii from modern seeps in the Gulf of Mexico. The Bullman Creek echinoid deposit probably represents a fossil analogue of the Gulf of Mexico Sarsiaster mass occurrence, indicating that the adaptation of spatangoid echinoids to chemosynthesis-based ecosystems ranges back at least to the earliest Oligocene.
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| 43. |
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| 44. |
- Thiel, Volker, et al.
(författare)
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Occurrence and fate of fatty acyl biomarkers in an ancient whale bone (Oligocene, El Cien Formation, Mexico)
- 2014
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Ingår i: Organic Geochemistry. - : Elsevier BV. - 0146-6380 .- 1873-5290. ; 68:Mar, s. 71-81
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Tidskriftsartikel (refereegranskat)abstract
- The taphonomic and diagenetic processes by which organic substances are preserved in animal remains are not completely known and the originality of putative metazoan biomolecules in fossil samples is a matter of scientific discussion. Here we report on biomarker information preserved in a fossil whale bone from an Oligocene phosphatic limestone (El Cien Fm., Mexico), with a focus on fatty acyl compounds. Extracts were quantitatively analysed using gas chromatography-mass spectrometry (GC-MS) and, to identify macromolecular-linked remains, demineralised extraction residues were subjected to catalytic hydropyrolysis (HyPy). To better recognise potential authentic (i.e. animal-derived) lipids, the data from the ancient bone were compared with those obtained from (i) the adjacent host sediment of the fossil and (ii) a recent whale (Phocoena phocoena) vertebra. In addition, the spatial distribution of organic and inorganic species was observed at the μm level by imaging MS (time-of-flight-secondary ion mass spectrometry, ToF-SIMS). Our results revealed a rather even distribution of hydrocarbon-, O- and N-containing ions in the trabecular network of the ancient bone. A different, more patchy arrangement of organic compounds was evident in the former marrow cavities that were partly cemented by clotted micrites of putative microbial origin. The concentration of fatty acids (FAs) in the ancient bone was in the permil range of the amount extracted from the recent whale vertebra. Endogenous compounds, including monoenoic n-C16and n-C18 as well as branched FAs, were identified in the fossil bone by comparison with the host sediment. Ca. 80% of the prevalent n-C16 and n-C18 moieties in the ancient bone were extractable as FAs, whereas ca. 20% were covalently bound in the non-saponifiable kerogen fraction. Ample pyrite precipitates, distinctive 10-methyl branched FAs and microbial microborings ("tunneling") indicate that sulfate reducers and collagen-degrading actinomycetes were central players in the microbial decomposition of the bone. Similarities with reported microbial FA patterns suggest that the FAs in the fossil bone were largely contributed by these microbial "last eaters". The results highlight some of the degradation and preservation mechanisms during marine FA diagenesis in the "natural laboratory" of bones, and therefore the processes that lead to either degradation, preservation, or introduction of these widespread biomolecules in the fossils of ancientmarine animals.
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| 45. |
- Wang, Xudong, et al.
(författare)
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New biogeochemical proxies in seep bivalves
- 2023
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Ingår i: South China Sea Seeps. - : Springer. - 9789819914937 - 9789819914944 ; , s. 115-128
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Bokkapitel (refereegranskat)abstract
- Reduced compounds dissolved in seeping fluids, such as methane and hydrogen sulfide, are the main energy sources in submarine cold seep systems, where they nourish the unique chemosynthesis-based ecosystems. Chemosymbiotic bivalves are the dominant macrofauna in many of these ecosystems and have been extensively studied due to their large biomass (hundreds of individuals per square meter), their symbiotic relationships with chemotrophic bacteria (methanotrophic bivalves: methane-oxidizing bacteria; thiotrophic bivalves: sulfur-oxidizing bacteria), and because they are unique archives of biogeochemical processes. In this chapter, we briefly introduce the advancements in seep bivalve research worldwide and then summarize the trophic modes and geographic distribution of seep bivalves in the South China Sea. Thereafter, the biogeochemical processes, such as the enzymatic strategy and energy transfer of seep bivalves, are generalized by integrating the trace elements and stable isotope data of the soft tissues and their corresponding calcareous shells of seep bivalves. Overall, we highlight the past contributions and current knowledge in this field and outline opportunities and future directions to expand this area of research.
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| 46. |
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