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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]

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]

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, eastern Canada), we have developed an event-biostratigraphic scheme based mainly on new analyses of several exploration wells. They include Demascota G-32, Hesper I-52, Onondaga E-84 and Wenonah J-75 on the continental shelf, as well as Shelburne G-29 and Shubenacadie H-100 on the continental slope. Several microfossil groups are involved in this study, most notably dinoflagellate cysts (dinocysts) and nannofossils, with the former generally providing more diverse assemblages and the latter more precise calibration with global correlations. Because most of the material studied is from cuttings samples, we have relied largely on last appearance datums (LADs). The scheme incorporates information from about 250 microfossil species (or groups of species), delimiting about 180 events, of which about 50 percent are based on nannofossils, some 46 percent on palynomorphs and 4 percent on foraminifera. Not all events occur in all wells and the scheme needs to be tested against future observations: nevertheless, it represents a considerable advance on previous schemes, which were based mostly on broad zones rather than detailed events. Moreover, it allows for a more refined assessment of ages of geological events, such as the late Paleocene gamma spike and the incision of the Wenonah Canyon. And it provides an accurate age context for ongoing stratigraphic, sedimentological and paleoenvironmental studies, and ultimately for a fuller understanding of petroleum systems on the Scotian Margin. [ABSTRACT FROM AUTHOR]