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Deep sea cold seeps are sites where hydrogen sulfide, methane, and other hydrocarbon-rich fluids vent from the ocean floor. They are an important component of Earth's carbon cycle in which subsurface hydrocarbons form the energy source for highly diverse benthic micro-and macro-fauna in what is otherwise vast and spartan sea scape. Passive continental margin cold seeps are typically attributed to the migration of hydrocarbons generated from deeply buried source rocks. Many of these seeps occur over salt tectonic provinces, where the movement of salt generates complex fault systems that can enable fluid migration or create seals and traps associated with reservoir formation. The elevated advective heat transport of the salt also produces a chimney effect directly over these structures. Here, we provide geophysical and geochemical evidence that the salt chimney effect in conjunction with diapiric faulting drives a subsurface groundwater circulation system that brings dissolved inorganic carbon, nutrient-rich deep basinal fluids, and potentially overlying seawater onto the crests of deeply buried salt diapirs. The mobilized fluids fuel methanogenic archaea locally enhancing the deep biosphere. The resulting elevated biogenic methane production, alongside the upward heat-driven fluid transport, represents a previously unrecognized mechanism of cold seep formation and regulation. [ABSTRACT FROM AUTHOR]

During the spring of 2018, residents Gary, David, and Rick Leblanc, found a near-horizontal burrow fossil within red sandstone along a ditch outcrop at Midland, New Brunswick. These red sandstones, [...]

A palynological (plant spores) biostratigraphic study of the Tournaisian (Early Carboniferous) aged sites between the townships of Bloomfield and Norton, New Brunswick is being conducted. Newly collected and historical samples [...]

We use new and existing nannofossil, palynological, and microfossil biostratigraphic data in conjunction with lithologic and geophysical logs from four wells to establish a series of sequence-stratigraphic events in the Mesozoic-Cenozoic of the Laurentian Subbasin of offshore Newfoundland, eastern Canada. Well biostratigraphic events are integrated with reflection seismic in the area to correlate regional seismic stratigraphic surfaces. The four wells are: Bandol-1, Emerillon C-56, East Wolverine G-37, and Heron H-73. We extend the event stratigraphic scheme previously developed for the Scotian Margin, offshore Nova Scotia, into new areas to the east along the southern Grand Banks, where we recognize four new well-log sequence stratigraphic events, and we modify the definition of a previously recognized regional surface. The new and modified regional surfaces are the Early Albian Unconformity, the Late Bathonian Maximum Flooding Surface (MFS), the Late Bajocian MFS (renamed from Bathonian/Bajocian MFS), the ?Bajocian/Toarcian Unconformity, and the Late Pliensbachian MFS. We recognize the "Avalon Unconformity" and "Base-Tertiary Unconformity" of previous studies as amalgamations of multiple smaller-scale unconformities and refine their age in the studied wells. A major improvement over our earlier Scotian Margin event schemes is the extension of the event stratigraphy into the Early Jurassic using a suite of marine biostratigraphic markers. We compare the Early Jurassic event scheme to Deep Sea Drilling Project Site 547B on the conjugate Moroccan Margin to better constrain potential source rock intervals and the early history of the central Atlantic Ocean. [ABSTRACT FROM AUTHOR]

In this study, we build on a foundation of previous biostratigraphic studies for the Scotian Basin, offshore eastern Canada, by conducting new quantitative multidisciplinary biostratigraphic studies of the Mesozoic sections in eight wells: Bonnet P-23, Chebucto K-90, Cohasset L-97, Glenelg J-48, Glooscap C-63, Mohican I-100, South Desbarres O- 76, and South Griffin J-13. These wells were chosen to provide good spatial coverage, stratigraphic penetration, and correlation with the seismic grid. We have also evaluated pre-existing biostratigraphic data and undertaken the well- log sequence-stratigraphic interpretation of Upper Triassic to Cenozoic sediments in 16 additional wells using a consistent multidisciplinary event scheme derived from the new wells. Key to the dating of some horizons has been integration of the palynology and micropaleontology (disciplines mostly used previously on the Scotian Margin) with new nannofossil data. Simultaneously we have closely integrated the biostratigraphic results with lithofacies, well-log, and seismic interpretations. Using this integrated approach, we have identified nine regionally mappable sequence-stratigraphic events (unconformities and maximum flooding surfaces, or MFSs): the Intra-Oligocene Unconformity; the Ypresian Unconformity; the Turonian/Cenomanian Unconformity; the Late Albian Unconformity; the Aptian/Barremian Unconformity; the Intra-Hauterivian MFS; the Near-Base Cretaceous Unconformity; the Tithonian MFS; and the Top-Callovian MFS. Additional events of local extent were also recognized in some wells. Our study has led to significant revision of some previous lithostratigraphic picks. The Early Jurassic on the Scotian Margin remains poorly resolved and may be represented by an unconformity on much of the basin periphery. Dans la presente etude, nous mettons a profit une base d'etudes biostratigraphiques anterieures pour le bassin Scotian, au large de l'Est du Canada, en effectuant de nouvelles etudes biostratigraphiques quantitatives multidisciplinaires des sections mesozo'iques dans huit puits : Bonnet P-23, Chebucto K-90, Cohasset L-97, Glenelg J-48, Glooscap C-63, Mohican I-100, South Desbarres O-76 et South Griffin J-13. Ces puits ont ete choisis afin de fournir une bonne couverture spatiale, une penetration stratigraphique et une correlation avec le reseau sismique. Nous avons aussi evalue les donnees biostratigraphiques existantes et nous avons entrepris l'interpretation de la diagraphie de la sequence stratigraphique des sediments du Trias superieur au Cenozo'que dans 16 puits additionnels en utilisant un plan d'evenements multidisciplinaires constants derive des nouveaux puits. La cle de la datation de certains horizons a ete l'integration de la palynologie et de la micropaleontologie (des disciplines surtout utilisees anterieurement sur la bordure Scotian) avec de nouvelles donnees de nannofossiles. En meme temps, nous avons soigneusement integre les resultats biostratigraphiques avec les lithofacies, les diagraphies et les interpretations sismiques. En utilisant cette approche integree, nous avons identifie neuf evenements cartographiables de sequences stratigraphiques (discordances et surfaces maximales d'inondation) : la discordance Intra-Oligocene, la discordance a l'Ypresien, la discordance au Turonien/Cenomanien, la discordance a l'Albien tardif, la discordance a l'Aptien/Barremien, la surface maximale d'inondation Intra-Hauterivien, la discordance pres de la base du Cretace, la surface maximale d'inondation du Tithonien et la surface maximale d'inondation du sommet du Callovien. D'autres evenements d'etendue locale ont aussi ete reconnus dans certains puits. Notre etude a conduit a une revision importante de certaines designations lithostratigraphiques. Le Jurassique precoce a la bordure Scotian demeure mal resolu et pourrait etre represente par une discordance sur une grande portion de la peripherie du bassin. [Traduit par la Redaction], Introduction The Scotian Margin is that region underlain by the continental shelf (Scotian Shelf) and slope (Scotian Slope) off Nova Scotia, southeastern Canada (Fig. 1A). It is part of the [...]

ABSTRACT In order to provide a detailed stratigraphic framework for the Late Cretaceous and Cenozoic basin fill of the Scotian Margin (the continental shelf and continental slope off Nova Scotia, [...]

A large sample of excellently preserved ammonites from concretions concentrated at a single horizon near the base of the Macdougall Point Member of the Christopher Formation (Aptian--Albian age; Early Cretaceous) is the basis for recognizing a new species of the boreal ammonite genus Pseudogastroplites (P. draconensis). The dimorphic nature of the genus is established, two variants are recognized (P. draconensis var. robusta and P. draconensis var. gracile), and the generic diagnosis is emended. Retention of the genus Pseudogastroplites Jeletzky, 1980 as distinct from Gastroplites McLearn, 1930 is proposed. The concretions also yield Pseudopulchellia flexicostata (Imlay, 1961), inoceramid bivalves, fish remains, and a palynological flora, and are dated as late middle Albian.

Basins along the Scotian Margin formed as part of North Atlantic opening, with Middle Triassic rifting leading to eventual Early-Middle Jurassic breakup. In the overlying passive margin succession, the Lower Cretaceous section is dominated by siliciclastic deposits reported from a variety of marine, shallow marine, and fluvial settings. In concert with ongoing palynological analyses, the present study contributes to the development of an event stratigraphic scheme by focussing on paleoenvironmental interpretations. Ichnological and sedimentological analyses were used to build a preliminary facies model, with an initial focus on the Upper Member of the Missisauga Formation conventional cores from Panuke B-90 and Cohasset A-52. Depositional conditions began as wave-influenced normal marine, with a distal Skolithos Ichnofacies. Restricted bay and possible deltaic deposits followed, with wave-influence decreasing up section and the ichnofossil assemblage gradually replaced by an impoverished archetypal expression of the Cruziana Ichnofacies. Overlying sandstone bodies are interpreted as tidally influenced estuarine channels based on the presence of herringbone cross-stratification, cyclical bedding, wood with Teredolites borings, and rare elements of a highly impoverished Skolithos Ichnofacies; however, barrier shoreface and tidal flats are present, suggesting a mixed wave- and tide-influenced estuary. Outer estuary conditions followed, with barrier shoreface, tidal flat and central bay deposits. Impoverished Cruziana Ichnofacies dominate, with elements of the Skolithos Ichnofacies locally present. The top of the Missisauga Formation shows indication of more normal marine conditions, with intermittent marine macrofauna and limited ichnological suites implying some degree of dysoxia. Storm influence is evident near the transition into the overlying Naskapi Member of the Logan Canyon Formation based on the presence of possible hummocky cross-stratification, a weakly stressed Cruziana Ichnofacies and more diverse marine macrofauna. Future work will entail detailed facies analysis and comparison with palynofacies to build a comprehensive paleoenvironmental model and a refined sequence stratigraphic framework. [ABSTRACT FROM AUTHOR]

In this study, we build on a foundation of previous biostratigraphic studies for the Scotian Basin, offshore eastern Canada, by conducting new quantitative multidisciplinary biostratigraphic studies of the Mesozoic sections in eight wells: Bonnet P-23, Chebucto K-90, Cohasset L-97, Glenelg J-48, Glooscap C-63, Mohican I-100, South Desbarres O-76, and South Griffin J-13. These wells were chosen to provide good spatial coverage, stratigraphic penetration, and correlation with the seismic grid. We have also evaluated pre-existing biostratigraphic data and undertaken the well-log sequence-stratigraphic interpretation of Upper Triassic to Cenozoic sediments in 16 additional wells using a consistent multidisciplinary event scheme derived from the new wells. Key to the dating of some horizons has been integration of the palynology and micropaleontology (disciplines mostly used previously on the Scotian Margin) with new nannofossil data. Simultaneously we have closely integrated the biostratigraphic results with lithofacies, well-log, and seismic interpretations. Using this integrated approach, we have identified nine regionally mappable sequence-stratigraphic events (unconformities and maximum flooding surfaces, or MFSs): the Intra-Oligocene Unconformity; the Ypresian Unconformity; the Turonian/Cenomanian Unconformity; the Late Albian Unconformity; the Aptian/Barremian Unconformity; the Intra-Hauterivian MFS; the Near-Base Cretaceous Unconformity; the Tithonian MFS; and the Top-Callovian MFS. Additional events of local extent were also recognized in some wells. Our study has led to significant revision of some previous lithostratigraphic picks. The Early Jurassic on the Scotian Margin remains poorly resolved and may be represented by an unconformity on much of the basin periphery. [ABSTRACT FROM AUTHOR]

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The Early Mississippian (known as 'Romer's Gap') marks the beginning of a critical point in tetrapod history as they transitioned from dominantly aquatic to more terrestrial ecosystems. This paleoecological expansion set the stage for the radiation of all terrestrial tetrapod crown groups. The exact timing for the transition into freshwater continental environments is poorly understood. However, new discoveries in Scotland, England, and Nova Scotia, represent rare exceptions; offering a glimpse into coastal terrestrial ecologies during 'Romer's Gap'. These sites have evidence for a marine-water connection suggesting a coastal paleogeographic position. In contrast, Early Mississippian sedimentary deposits of the Moncton Subbasin in southern New Brunswick (NB) are interpreted as freshwater intra-continental conditions (lacustrine, wetland, fluvial, alluvial settings). A single stratigraphic horizon in the Albert Formation (Hiram Brook Member), exposed near Norton, NB, has yielded abundant tetrapod footprints. Preliminary assessments suggest at least four trackway ichnogenera: cf. Characichnos, cf.Matthewichnus, cf.Hylopus, and cf.Batrachichnus and a fifth trackway that may represent a new ichnogenus. Footprints range in size from 1 to 3 cm, suggesting that tetrapods were smaller than those documented from near time-equivalent sites in Nova Scotia, but are comparable in size to skeletal fossils described from younger strata in Scotland. These footprints are interpreted to be preserved in interfluvial crevasse splays associated with wetland forests dominated by Lepidodendropsis lycopods and Aneimites ferns preserved in their ecological context. The relatively large sample size of footprints suggests that a community of tetrapods were present and part of a diverse ecosystem, adapted to terrestrial and semi-aquatic continental environments in the earliest Mississippian. Additional trackways from slightly younger redbed playa lake deposits in the Sussex Group suggest tetrapods were also venturing into semi-arid continental environments. The ichnofossil assemblage from NB demonstrates considerable variation in ichnotaxa morphology and paleoenvironmental context from sites of approximately equivalent age. [ABSTRACT FROM AUTHOR]

The Carboniferous Joggins Fossil Cliffs UNESCO World Heritage Site, located in Nova Scotia, has long been known for its extensive paleobiodiversity. The ichnofossil record at Joggins is less known compared to body fossils. The late citizen scientist Donald Reid (known as "The Keeper of the Cliffs") contributed significantly to our understanding of the fossil record at Joggins. In his extensive ichnological collections is a morphologically unique "shrimp shaped" cubichnia (resting trace). The trace fossil is associated with faint invertebrate trackways that lead up to the resting trace and verifies the identification of this specimen as an invertebrate resting trace. The trace fossil was recovered from the upper Joggins Formation (876 m above the base) and was found in fine-grained rippled sandstones that are interpreted to be from an Open-Water to Poorly-Drained Lithofacies Assemblage transition. Horseshoe crab walking traces (Kouphichnium) are well known from this trace fossil horizon. The trace fossil specimen also has examples of invertebrate resting traces Selenichnites and Rusophycus preserved in convex hyporelief, that are commonly ascribed to horseshoe crabs and crustaceans, respectively, when found in freshwater paleoenvironments. This stratigraphic interval has previously yielded body fossils of Pygocephalus shrimp preserved in organic rich limestones and sideritic ironstone nodules. The Joggins Cliffs have yielded an abundance of trace fossils ascribed to horseshoe crabs, yet only two of their body fossils. Pygocephalus shrimp body fossils are common at Joggins, yet no trace fossils have yet been assigned to this invertebrate and perhaps have gone unrecognized. We interpret the trace fossil to have been produced by a Pygocephalus shrimp based on its morphological similarities to known body fossils from the Joggins Formation that are found in proximity to the trace fossil horizon. This new trace fossil morphology likely warrants a new ichnotaxon. [ABSTRACT FROM AUTHOR]

The Fundy Basin of Nova Scotia and New Brunswick, Canada, is the most northern extent of the Triassic-Jurassic Newark Supergroup on land. Mesozoic sedimentary rocks in New Brunswick are rare by comparison to the neighbouring province of Nova Scotia. The Upper Triassic is known for the oldest dinosaurs in Canada, together with other vertebrates, invertebrates, plants, and ichnofossils from the Upper Triassic of the Wolfville and Blomidon formations. The present study has found the first evidence of vertebrate life from the Triassic of New Brunswick in the Alma area the Bay of Fundy. A single horizon from strata at Waterside Beach has yielded isolated vertebrate bones (vertebral element, limb bone, isolated tooth and bone fragments), while at a second outcrop along Dennis Beach, a single horizon of mudstone preserved vertebrate ichnofossils. UAV-based photographs have been collected to digitally preserve 3D models of the outcrops. This documents the current context, as these coastal sites experience tidal erosion, exposing new outcrop. The ichnoassemblage includes footprints of dinosauromorphs (e.g., lagosuchians; ichnotaxon: Rotodactylus), lepidosauromorphs/archosauromorphs (ichnotaxon: Rhynchosauroides), Archosauriformes and "Rauisuchia" (ichnotaxon: Synaptichnium), and an unidentified dinosaur-like track. Rotodactylus is thought to represent dinosauromorphs that are close to the beginning of the dinosaurian clade and is an index ichnogenus with a limited stratigraphic range of Early Triassic (latest Olenekian) through the Middle Triassic (Anisian to the earliest Ladinian). The elements of the fossil assemblage described here are commonly found together and comparable to other sites of similar Early-Middle Triassic age in Morocco, South America, and Poland. This restricts the age of the Triassic strata at Dennis Beach and the vertebrate footprints preserved at that locality to between the latest Lower Triassic and the Middle Triassic, making it the oldest evidence of vertebrates from the Mesozoic in Canada inferred from footprints and isolated bones. [ABSTRACT FROM AUTHOR]

Nova Scotia has potential undiscovered hydrocarbon reservoirs in the deep-water region of the Scotian Margin. Deep-water environments can involve major challenges with high exploration risk because the presence, quality, size, and distribution of source and reservoir rocks are still relatively unknown in many areas. New data are therefore needed to de-risk offshore exploration for the next generation of discoveries. This research project investigates the shallow (0 to 3 km) Cenozoic section of BP's Tangier 3D Seismic Survey, located on the central Scotian Slope. The Tangier 3D Area is one of the most geologically complex regions of the Scotian Slope encompassing two salt structural regions: the western diapiric and eastern canopy complex subprovinces. Seismic interpretation and attribute analysis of the Cenozoic suggests that the region hosts a complex subsurface geology comprising of modern-day and paleo-channels and canyons, sediment drifts, slope failure complexes, and slope drapes. Salt-related structural features, which some occur deeper than 3 km, include welds, wings, feeders, pedestals, rollers, withdrawal minibasins, rafted overburden, and growth and crestal faults. Also observed within the Tangier 3D Area are three amplitude anomalies, which two are situated above diapirs and one above a salt canopy, interpreted to be direct hydrocarbon indicators (DHIs). The shallow-level DHIs strongly indicate the presence of migrating fluids. The architectural investigation of these DHIs provides evidence of a working petroleum system governed by salt mobility, which provides migration pathways for deeply sourced fluids. However, further study is needed to determine if the fluids filling these DHIs are thermogenic hydrocarbons escaped from deeper Jurassic or Cretaceous sources and breached reservoirs. [ABSTRACT FROM AUTHOR]

Biostratigraphic studies of Mesozoic-Cenozoic strata along the Scotian Margin began in the early 1970s, focussing on zonation schemes for separate disciplines. Subsequent works, however, have evolved into an event stratigraphic approach, combining palynologic with micropaleontologic and nannofossil events, as well as seismic horizons. Extensive taxonomic treatment of Late Cretaceous and Cenozoic palynomorphs from the Scotian Margin were also undertaken but did not encompass the Triassic to Early Cretaceous interval. Thus, we aim to develop a detailed taxonomic review and a comprehensive event-stratigraphic scheme for this earlier interval based on palynology, integrated with paleoenvironmental and sequence stratigraphic interpretations. Our initial focus is on conventional cores in Panuke B-90 and Cohasset A-52 to develop a composite Lower Cretaceous succession, supported by analyses of cuttings from deeper wells that penetrate pre-Cretaceous strata (e.g., Argo F-38) to provide a broader context. The sedimentary facies, trace fossils and initial palynologic data of the Panuke B-90 cores indicate, at the base, a transition from a shoaling marine to a mainly estuarine setting, followed by a transgressive cycle through the Upper Member of the Missisauga Formation that culminates in normal marine environments again near the base of the overlying Naskapi Member of the Logan Canyon Formation. It is apparent that this transgression is not continuous but intercalated with smaller cycles, well documented by the fluctuations of terrestrial (pollen and spores) versus marine (mainly dinoflagellate cysts) palynomorph dominance across this interval. The assemblages from the Upper Member of the Mississauga Formation are typical of the Early Cretaceous, probably Barremian. An Aptian age is expected for the overlying Naskapi Member based on previous studies that reported the presence of the age-diagnostic ammonite Deshayesites sp. Ongoing work on the Panuke B-90 conventional cores and coeval successions will contribute to a comprehensive event-stratigraphic framework for the Scotian Margin. [ABSTRACT FROM AUTHOR]