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We reconstruct the subtropical North Atlantic water column structure during the Miocene Climate Optimum warming (MCO; 17–14.8 Ma) and the Middle Miocene Climate Transition cooling (MMCT; 14.8–12.8 Ma) by analyzing δ18O and δ13C in four species of foraminifera (surface dwellers Dentoglobigerina altispira and Trilobatus quadrilobatus, thermocline dweller Dentoglobigerina venezuelana, and benthic Planulina wuellerstorfi) from Site 558 (37.8°N). At the end of the MCO, δ18O of surface and thermocline dwellers increased by >1‰, suggesting at least 2°C cooling in the upper ocean as ice growth increased global δ18Osw by ∼0.5‰. The difference in δ18O values between thermocline and surface-dwelling species increased during the MMCT, coinciding with the development of a largely permanent East Antarctic Ice Sheet, and persisted into the Late Miocene. We interpret this increase in vertical δ18O gradient as a strengthening of the thermocline due to intensification of subtropical gyre circulation in response to the MMCT cooling.

We evaluate the Cretaceous stratigraphy and carbon sequestration potential of the northern Baltimore Canyon Trough (NBCT) using >10,000 km of multi-channel seismic profiles integrated with geophysical logs, biostratigraphy, and lithology from 29 offshore wells. We identify and map six sequences resolved primarily at the stage level. Accommodation was dominated by thermal and non-thermal subsidence, though sequence boundaries correlate with regional and global sea-level changes, and the record is modified by igneous intrusion, active faulting, and changes in sediment supply and sources. Our stratigraphic maps illustrate a primary southern (central Appalachian) Early Cretaceous source that migrated northward during the Aptian and Albian. During the Cenomanian, sedimentation rates in the NBCT increased and depocenters shifted northward and landward. We show that deposition occurred in three phases: (1) earlier Cretaceous paleoenvironments were primarily terrestrial indicated by variable amplitude, chaotic seismic facies, serrated gamma logs, and heterolithic sandstones and mudstones with terrestrial microfossils; (2) the Albian to Cenomanian was dominated by deltaic paleoenvironments indicated by blocky, funnel-shaped, gamma-ray logs and clinoforms characterized by continuous high-amplitude seismic reflections with well-defined terminations; and (3) the Cenomanian and younger was marine shelf, inferred from mudstoneprone lithologies, peak gamma-ray values in well logs, and foraminiferal evidence. Long-term transgression and maximum water depths at the Cenomanian/Turonian boundary correlative with Ocean Anoxic Event 2 were followed by a regression and relative sea-level fall. We show that porous and permeable sandstones of three Aptian to Cenomanian highstand systems tracts are high-volume reservoirs for supercritical CO2 storage that are confined by overlying deep water mudstones.

We applied quantitative methods to previously published biostratigraphic data from the Baltimore Canyon Trough (offshore of the Mid-Atlantic U.S.A.) to provide an improved chronostratigraphic framework for Cretaceous sequences. Here, we successfully used graphic correlation of 228 planktonic foraminifera, nannofossil, and palynological events spanning 22 wells to define assemblage and interval zones as well as major paleoenvironmental changes in the Dawson Canyon, Logan Canyon (three sequences), and Missisauga Formations (two sequences, undifferentiated here). Ranking and scaling techniques were not successful because of the of the limited number of usable biostratigraphic markers. The ages of the sequences previously identified using well logs and seismic profiles were temporally constrained based on chronostratigraphically significant biostratigraphic markers that we identified: the late Cenomanian to Turonian DCx sequence (Rotalipora cushmani and Thalmanninella greenhornensis); the early Cenomanian LC1 sequence; the middle and late Albian LC2 sequence (Braarudosphaera africana, Planomalina buxtorfi, and Spinidinium vestitum); the late Aptian LC3 sequence (Cyclonephelium tabulatum); and the early Aptian to Barremian Missisauga sequences (Aptea anaphrissa, Pseudoceratium pelliferum, and Muderongia simplex). These five biostratigraphic associations are correlated with six prominent seismic reflectors and sequence boundaries that can be traced across the basin. Duration of hiatuses associated with these sequence boundaries are uncertain, though our Monte Carlo analysis allows extraction of age estimates from broad and sometimes contradictory ranges and suggests correlation of hiatuses with global sea-level falls. Together, these seismic and biostratigraphic interpretations can be applied (1) to evaluate reservoir continuity and the viability of offshore carbon storage reservoirs in the Baltimore Canyon Trough, (2) to better define the tectonostratigraphic evolution of the basin, and (3) to contribute to the understanding of regional and global variations in Cretaceous sea level.

Axonal transport is key to neuronal function. Efficient transport requires specific motor-cargo association in the soma, yet the mechanisms regulating this early step remain poorly understood. We found that EBP-1, theC. elegansortholog of the canonical microtubule end binding protein EB1, promotes the specific association between kinesin-3/KIF1A/UNC-104 and Dense Core Vesicles (DCVs) prior to their axonal delivery. Using single-neuron,in vivolabelling of endogenous cargo and EBs, we observed reduced axonal abundance and reduced secretion of DCV cargo, but not other KIF1A/UNC-104 cargo, inebp-1mutants. This reduction could be traced back to fewer exit events from the cell body, where EBP-1 colocalized with the DCV sorting machinery at the trans Golgi, suggesting that this is the site of EBP-1 function. In addition to its microtubule binding CH domain, mammalian EB1 interacted with mammalian KIF1A in an EBH domain dependent manner, and expression of mammalian EB1 or the EBH domain was sufficient to rescue DCV transport inebp-1mutants. Our results suggest a model in which kinesin-3 binding and microtubule binding by EBP-1 cooperate to transiently enrich the motor near sites of DCV biogenesis to promote motor-cargo association. In support of this model, tethering either EBP-1 or a kinesin-3 KIF1A/UNC-104 interacting domain from an unrelated protein to the Golgi restored the axonal abundance of DCV proteins inebp-1mutants. These results uncover an unexpected role for a microtubule associated protein and provide insight into how specific kinesin-3 cargo are delivered to the axon.

The International Union of Geological Sciences Executive Committee (IUGS EC) voted on 13 October 2021 to ratify a proposal for the Neogene subseries/subepochs to have formal status. They are now incorporated into a six-tiered chronostratigraphic hierarchy within the International Chronostratigraphic Chart (ICC). The Lower/Early Miocene Subseries/Subepoch comprises the Aquitanian and Burdigalian stages/ages, the Middle Miocene Subseries/Subepoch comprises the Langhian and Serravallian stages/ages, the Upper/Late Miocene Subseries/Subepoch comprises the Tortonian and Messinian stages/ages, the Lower/Early Pliocene Subseries/Subepoch comprises the Zanclean Stage/Age and the Upper/Late Pliocene Subseries/Subepoch comprises the Piacenzian Stage/Age. This ratification is an important move towards both a common language in the wider Earth Sciences community and a step forward in the unification of Cenozoic chronostratigraphy, with Neogene and Quaternary subseries/subepochs now formalized.

The mid-Atlantic coastal plain (eastern United States) preserves high-resolution records of the Paleocene-Eocene Thermal Maximum (PETM) and attendant carbon isotope excursion (CIE), though preservation is highly variable from site to site. Here, we use a dip transect of expanded (as much as 15 m thick) PETM sections from the New Jersey coastal plain to build a cross-shelf PETM depositional model that explains the variability of these records. We invoke enhanced delivery of fine-grained sediments, due to the rapid environmental changes associated with this hyperthermal event, to explain relatively thick PETM deposits. We utilize δ13Cbulk, percent CaCO3, and percent coarse fraction (>63 μm) data, supported by biostratigraphic records, to correlate sites along a paleoslope dip transect. Updip cores from Medford, New Jersey, preserve expanded sections of the initiation of the PETM and the earliest portion of the CIE. Medial sites (Wilson Lake, Millville) preserve an expanded CIE body, and downdip Bass River records the CIE recovery. We interpret this pattern to reflect the progradation of clinoform foresets across the paleoshelf via fluid mud, similar to modern high-sediment-supply rivers and adjacent muddy shelves (e.g., the Amazon, Mahakam [Indonesia], and Ayeyarwady [Myanmar] Rivers). Our subaqueous-clinoform delta model explains the pattern of the CIE records and provides a framework for future PETM studies in the region.

The peak "hothouse" interval of the Turonian-Coniacian (93-87 Ma) is represented on the U.S. middle Atlantic Coastal Plain by sequences of the Raritan/Bass River, Magothy, and Cheesequake Formations deposited on a passive continental margin as mixed wave-, tide-, and river dominated deltas. We apply sequence stratigraphy integrated with biostratigraphy to identify and map two major sequence boundaries separating the Raritan/Bass River, Magothy, and Cheesequake Formations and four to five (Mg1, Mg2, Mg3, ?Mg4, Mg5) Magothy sequences using continuous cores, outcrops, and geophysical logs in New Jersey. We extend correlations into New York and Delaware using well logs. The Magothy sequences disconformably overlie the well-dated (>93 Ma) lower Turonian to Cenomanian marine Raritan/Bass River sequences and are disconformably overlain by the marine Cheesequake Formation, which straddles the Coniacian/Santonian boundary. A "mid-Turonian" hiatus (ca. 93-90 Ma) associated with this major disconformity is a global sequence boundary (K-Tu4) reflecting a ~ 25 m sea-level lowering based on published NJ and Russian Platform backstripping records that indicate this was a major lowering of Global Mean Sea Level (GMSL).Higher-order (~1 Myr scale) sequence boundaries bracketing Mg1-Mg5 apparently correlate with global sequences but are only associated with low-amplitude (

We developed a sequence stratigraphic framework for the (Barremian to lower Cenomanian) fluvial–deltaic (primarily delta plain) Potomac Formation in the Medford, New Jersey, Fort Mott, New Jersey, and Summit Marina, Delaware coreholes. Previous studies have correlated distinctive lithologic units with attendant pollen zones and identified tentative sequence boundaries between lithologic units I (Barremian to lower Aptian, pollen Zone I), II (Aptian to lowermost Cenomanian, pollen Zone II), and III (lower Cenomanian, pollen Zone III) at all three sites. Here, we further subdivide these units into packages known as fluvial aggradation cycles (FACs). An analysis of FAC stacking patterns reveals potential sequence boundaries and systems tracts. FACs indicate that major lithologic unit boundaries are also sequence boundaries, indicate tentative higher-order sequence boundaries, and provide potential additional correlative surfaces among Potomac Formation sites. Our study demonstrates the applicability of the FAC method to identify stacking patterns and sequence stratigraphic surfaces in fluvial–deltaic deposits and demonstrates that FACs are excellent tools to decipher the difficult-to-correlate surfaces.

We evaluate Cretaceous depositional sequences on approximately 4400 km (∼2700 mi) of newly released multichannel seismic profiles and five wells on the continental shelf in the southern Baltimore Canyon trough and tie the data to three wells drilled onshore in the Maryland coastal plain. Seismic geometries coupled with facies and biostratigraphy from the wells are used to delineate mid-Cretaceous (Aptian–Turonian) depositional sequences and paleogeography. Beneath these sequences, 400–1000 m (1300–3300 ft) of Lower Cretaceous sedimentary rocks underlie the modern shelf. They thicken along strike to the southwest, implying a southern sediment source. Aptian to Cenomanian sediments were deposited in shelf to nearshore settings. A landward movement of the depocenter and a shift toward facies indicative of deeper paleodepths marks a 107-yr mid-Cretaceous transgression, within which we identify five sequences. A composite maximum flooding surface (MFS) within the uppermost of these retrogradational units is associated with the Cenomanian–Turonian boundary and ocean anoxic event 2. Shingled, lower Turonian seismic reflections prograde across the outer shelf, downlapping onto the composite MFS, and are truncated by a mid-Turonian sequence boundary. The Upper Cretaceous section thickens seaward and along strike to the northeast, implying a northern source and little Late Cretaceous accommodation beneath the modern shelf. Mid-Cretaceous strata offshore Maryland are likely sand-prone, considering their proximity to the correlative fluvial facies of the onshore Potomac Group. These potential reservoir sands are capped by regional confining units generated by 107-yr global mean sea-level flooding events and are excellent targets for supercritical carbon storage.

Estimating the trophic position of predators in food webs using stable isotopes requires establishing a “baseline”, typically served by bivalves or snails. However, the frequent absence of such organisms in lakes leaves researchers in a difficult situation. Here we test the hypothesis that trophic position (TP) of largemouth bass (LB; Micropterus salmoides) in lakes can be estimated from δ15N of benthic organic material (BOM) in littoral surficial sediment. δ15NLB as a function of δ15NBOM was significant across 51 lakes with an R2 of 0.84, supporting our hypothesis. In a subset of six lakes, the mean TPLB did not differ significantly when calculated using baselines of δ15N in BOM, unionid mussels (UN), gastropods (SN), or from a stable isotope mixing model. In a subset of 26 lakes, mean TPLB calculated from δ15NBOM and δ15NUN baselines were not significantly different, but TPLB calculated using δ15NBOM was not significantly correlated with TPLB calculated using δ15NUN. Although δ15NBOM should not be used interchangeably with δ15NUN as a baseline for estimating TPLB, δ15NBOM can be useful as a separate baseline where estimates of fish TP are needed in all study lakes given that mussels are frequently absent and BOM is always available for collection.

We identified and described Potomac Formation paleosols from three coreholes in New Jersey and Delaware to interpret depositional history and reconstruct regional landscapes during the climatic transition from the Early to the Late Cretaceous. In total, 103 paleosol profiles were described and grouped into five pedotypes (gray, gray-red, purple, red, and brown) ranging in pedogenic maturity from: 1) weakly developed, immature soils formed under poor drainage conditions (gray and gray-red); to 2) moderately developed soils formed under alternating drainage conditions (purple and red); to 3) well-developed, mature soils formed under well-drained conditions (brown). Geochemical and stable-isotope proxies (Ba/Sr and δ18O on sphaerosiderite) are presented to constrain paleoprecipitation and/or fluvial position and drainage conditions. Potomac Formation Unit I (Barremian to lower Albian) generally displays well-drained, stable landscape conditions upsection, with paleoprecipitation being the main control on development of paleosol type. Potomac Formation Units II (lower Albian to lower Cenomanian) and III (lower Cenomanian) have variable drainage and landscape conditions upsection. Paleoprecipitation exerted a controlling role in the development of paleosol type lower in Unit II, while base-level changes exerted greater influence on landscape conditions upsection into Unit III. Geochemical proxies provide evidence that Unit I was subhumid with episodes of saturation and overall better drainage conditions relative to the overlying units. Units II and III were deposited under more waterlogged conditions, experiencing subhumid to humid conditions, with episodes of enhanced drainage from base-level fall. The use of these proxies is consistent with interpretations made using the macro-features and micro-features of the paleosols and sphaerosiderite δ18O, and emphasizes that the main long-term environmental control on landscape development during this period was initially paleoprecipitation, with progressive influence from base-level changes.

Oyster habitat restoration seeks to recover lost ecosystem services including increased provisioning of refuge and foraging habitat for fish and invertebrate communities. The goal of this study was to quantify the ecosystem service benefit of habitat provisioning in Ninigret Pond, RI, following oyster restoration. Four metrics were measured, abundance, biomass, species richness, and diversity, as well as isotopic composition in fish and invertebrates collected seasonally from restored oyster, aquaculture, and bare sediment sites, to examine whether the oyster habitat outperformed the bare sediment habitat. Sampling locations were chosen in Foster's Cove north and south, Grassy Point, South Sanctuary, and an Aquaculture lease; each had two restored oyster sites and one bare sediment site. Each site was sampled using a box trap, seine net, shrimp trap, and minnow trap. Oyster habitats had significantly greater metrics than did bare sediment habitats in some comparisons from the box trap and seine net samples. Restored oyster sites at South Sanctuary had lower metric values than the other oyster sites. Metrics from the Aquaculture sites were comparable to the Foster's Cove and Grassy Point restored oyster sites and often outperformed South Sanctuaryrestored oyster sites. Seasonally, spring and autumn samples tended to have higher abundance and biomass values than summer samples. Isotopic composition of five species occurring at both restored oyster and bare sediment sites demonstrated some differences in the trophic levels between species but not between habitat types. In Ninigret Pond, fish and invertebrate abundance, biomass, species richness, and diversity benefit from the use of oyster and bare sediment habitats. Coastal zone managers interested in restoring the ecological function of oyster reefs to support fish and invertebrate communities should consider strategically locating restoration projects within the mosaic of structured habitats and monitoring them for selected ecosystem services.

In an attempt to understand the relative importance of climate and tectonics in modulating coarse-grained sediment flux to a tectonically active basin during what many researchers believe to be a greenhouse period, we have studied the Middle Eocene deep-marine Ainsa Basin, Spanish Pyrenees. We use orbital tuning of many spectral gamma-ray-logged fine-grained siliciclastic sections, already shown to contain Milankovitch frequencies, in conjunction with a new high-resolution palaeomagnetic study through the basin sediments, to identify polarity reversals in the basin as anchor points to allow the conversion of a depth-stratigraphy to a chronostratigraphy. We use these data, in conjunction with a new age model incorporating new biostratigraphic data, to pace the development of the deep-marine sandy submarine fans over c. 8 million years. Timing for the sandy submarine fans shows that, unlike for the fine-grained interfan sediments, coarse-grained delivery to the basin was more complex. Approximately 72% of the sandy fans are potentially coincident with the long-eccentricity (400 kyr) minima and, therefore, potentially recording changing climate. The stratigraphic position of some sandy fans is at variance with this, specifically those that likely coincide with a period of known increased tectonic activity within the Ainsa Basin, which we propose represents the time when the basin was converted into a thrust-top basin (Gavarnie thrust sheet), presumably associated with rapid uplift and redeposition of coarse clastics into deep-marine environments. We also identify sub-Milankovitch climate signals such as the c. 41.5 Ma Late Lutetian Thermal Maximum. This study demonstrates the complex nature of drivers on deep-marine sandy fans in a tectonically active basin over c. 8 Myr. Findings of this study suggest that, even during greenhouse periods, sandy submarine fans are more likely linked with times of eccentricity minima and climate change, broadly consistent with the concept of lowstand fans. However, hysteresis effects in orogenic processes of mountain uplift, erosion and delivery of coarse siliciclastics via fluvial systems to coastal (deltaic) and shallow-marine environments likely contributed to the complex signals that we recognize, including the 2–3 Myr time gap between the onset of deep-marine fine-grained sediments in the early development of the Ainsa Basin and the arrival of the first sandy fans. Supplementary Materials: Filtered records for each of the analysed gamma-ray logged sections. Anchor points, SARs tables and graphs and alternative tuning sections are available at: https://doi.org/10.6084/m9.figshare.c.5132975

Global mean sea level estimated for the Cenozoic using a new astronomically calibrated Pacific benthic foraminiferal δ18O splice., Using Pacific benthic foraminiferal δ18O and Mg/Ca records, we derive a Cenozoic (66 Ma) global mean sea level (GMSL) estimate that records evolution from an ice-free Early Eocene to Quaternary bipolar ice sheets. These GMSL estimates are statistically similar to “backstripped” estimates from continental margins accounting for compaction, loading, and thermal subsidence. Peak warmth, elevated GMSL, high CO2, and ice-free “Hothouse” conditions (56 to 48 Ma) were followed by “Cool Greenhouse” (48 to 34 Ma) ice sheets (10 to 30 m changes). Continental-scale ice sheets (“Icehouse”) began ~34 Ma (>50 m changes), permanent East Antarctic ice sheets at 12.8 Ma, and bipolar glaciation at 2.5 Ma. The largest GMSL fall (27 to 20 ka; ~130 m) was followed by a >40 mm/yr rise (19 to 10 ka), a slowing (10 to 2 ka), and a stillstand until ~1900 CE, when rates began to rise. High long-term CO2 caused warm climates and high sea levels, with sea-level variability dominated by periodic Milankovitch cycles.

Foraminifera from salt-marsh environments have been used extensively in quantitative relative sea-level reconstructions due to their strong relationship with tidal level. However, the influence of temporal and spatial variability of salt-marsh foraminifera on quantitative reconstructions remains unconstrained. Here, we conducted a monitoring study of foraminifera from four intertidal monitoring stations in New Jersey from high marsh environments over three years that included several extreme weather (temperature, precipitation, and storm surge) events. We sampled four replicates from each station seasonally (four times per year) for a total of 188 samples. The dead foraminiferal assemblages were separated into four site-specific assemblages. After accounting for systematic trends in changes in foraminifera over time among stations, the distribution of foraminiferal assemblages across monitoring stations explained ~87% of the remaining variation, while ~13% can be explained by temporal and/or spatial variability among the replicate samples. We applied a Bayesian transfer function to estimate the elevation of the four monitoring stations. All samples from each station predicted an elevation estimate within a 95% uncertainty interval consistent with the observed elevation of that station. Combining samples into replicate- and seasonal-aggregate datasets decreased elevation estimate uncertainty, with the greatest decrease in aggregate datasets from Fall and Winter. Information about the temporal and spatial variability of modern foraminiferal distributions was formally incorporated into the Bayesian transfer function through informative foraminifera variability priors and was applied to a Common Era relative sea-level record in New Jersey. The average difference in paleomarsh elevation estimates and uncertainties using an informative vs uninformative prior was minimal (

Synaptic vesicles (SVs) transmit signals by releasing neurotransmitters from specialized synaptic regions of neurons. In the synaptic region, SVs are tightly clustered around small structures called active zones. The motor KIF1A transports SVs outward through axons until they are captured in the synaptic region. This transport must be guided in the forward direction because it is opposed by the dynein motor, which causes SVs to reverse direction multiple times en route. The core synapse stability (CSS) system contributes to both guided transport and capture of SVs. We identified Sentryn as a CSS protein that contributes to the synaptic localization of SVs in Caenorhabditis elegans. Like the CSS proteins SAD Kinase and SYD-2 (Liprin-α), Sentryn also prevents dynein-dependent accumulation of lysosomes in dendrites in strains lacking JIP3. Genetic analysis showed that Sentryn and SAD Kinase each have at least one nonoverlapping function for the stable accumulation of SVs at synapses that, when combined with their shared functions, enables most of the functions of SYD-2 (Liprin-α) for capturing SVs. Also like other CSS proteins, Sentryn appears enriched at active zones and contributes to active zone structure, suggesting that it is a novel, conserved active zone protein. Sentryn is recruited to active zones by a process dependent on the active zone-enriched CSS protein SYD-2 (Liprin-α). Our results define a specialized group of active zone enriched proteins that can affect motorized transport throughout the neuron and that have roles in both guided transport and capture of SVs.

Dense core vesicles (DCVs) can transmit signals by releasing neuropeptides from specialized synaptic regions called active zones. DCVs reach the active zone by motorized transport through a long axon. A reverse motor frequently interrupts progress by taking DCVs in the opposite direction. “Guided transport” refers to the mechanism by which outward movements ultimately dominate to bring DCVs to the synaptic region. After guided transport, DCVs alter their interactions with motors and enter a “captured” state. The mechanisms of guided transport and capture of DCVs are unknown. Here, we discovered two proteins that contribute to both processes in Caenorhabditis elegans. SAD kinase and a novel conserved protein we named Sentryn are the first proteins found to promote DCV capture. By imaging DCVs moving in various regions of single identified neurons in living animals, we found that DCV guided transport and capture are linked through SAD kinase, Sentryn, and Liprin-α. These proteins act together to regulate DCV motorized transport in a region-specific manner. Between the cell body and the synaptic region, they promote forward transport. In the synaptic region, where all three proteins are highly enriched at active zones, they promote DCV pausing by inhibiting transport in both directions. These three proteins appear to be part of a special subset of active zone-enriched proteins because other active zone proteins do not share their unique functions.

We document Neogene benthic foraminiferal biofacies changes on a depth transect of six Gulf of Mexico industry wells (sidewall and cutting samples) that is oblique to the coast and extends from Main Pass to Green Canyon (offshore Alabama to Louisiana, USA). Calcareous nannofossil and planktonic foraminiferal biostratigraphic control provides the framework to make interwell comparisons of the benthic foraminiferal biofacies; these comparisons provide the basis for paleobathymetric and paleoenvironmental interpretations and to identify useful benthic foraminiferal biostratigraphic markers in this region.Benthic foraminiferal faunas indicate that Neogene paleodepths were slightly shallower at the eastern wells and deepened towards the western wells. Calcareous benthic foraminiferal biofacies dominated by Uvigerina spp. indicate that paleoenvironments characterized by low-oxygen conditions and/or high productivity occurred periodically during deposition along the transect. This is supported by repeated occurrences of a distinctive assemblage of agglutinated foraminifera (known as the “Agua Salada Fauna”) that is typical of dysaerobic environments.Evidence of intensified low-oxygen/high-productivity environments are recorded in lowermost Middle Miocene sediments at some locations and are present at all wells in Upper Miocene deposits. In Upper Miocene-Pliocene sediments, oxygen levels appear to have been related to paleodepth, indicating that the development of lower oxygen conditions was the result of an expansion or migration of the oxygen minimum zone. Our results are consistent with a global cause for the expansion of the oxygen minumum zone during the Late Miocene and widespread increase in export production. Our study shows that despite problems in well cuttings (cavings, inconsistent sampling) and complications in regional salt and fault tectonics, well transects can provide coherent benthic foraminiferal biofacies patterns that reveal paleobathymetric and paleoenvironmental changes in the Gulf of Mexico.

The rate of relative sea-level (RSL) rise at Sandy Hook, NJ (4.0 ± 0.5 mm/yr) was higher than The Battery, NY (3.0 ± 0.3 mm/yr) from 1900 to 2012 despite being separated by just 26 km. The difference cannot be explained by differential glacial isostatic adjustment (GIA; 1.4 ± 0.4 and 1.3 ± 0.4 mm/yr RSL rise, respectively) alone. We estimate the contribution of sediment compaction to subsidence at Sandy Hook using high-resolution grain size, percent organic matter, and porosity data from three upper Quaternary (≤13,350 cal yr) cores. The organic matter content (

Many sequence stratigraphic approaches have used relative sea-level curves that are dependent on models or preconceived notions to recognize depositional sequences, key stratal surfaces, and systems tracts, leading to contradictory interpretations. Here, we urge following basic sequence stratigraphic principles independent of sea-level curves using seismic terminations, facies successions and stacking patterns from well logs and sections, and chronostratigraphic data to recognize sequence boundaries, other stratal surfaces, parasequences, and systems tracts. We provide examples from the New Jersey siliciclastic paleoshelf from the: 1) early Miocene using academic-based chronostratigraphic, seismic, core, downhole, and core log data, and 2) mid-Cretaceous using commercial well-log, seismic, and biostratigraphic data. We use classic criteria to identify sequence boundaries on seismic profiles by reflection terminations (onlap, downlap, erosional truncation, and toplap), in cores by surfaces of erosion associated with hiatuses detected using biostratigraphy and Sr-isotope stratigraphy and changes in stacking patterns, and in logs by changes in stacking patterns. Maximum flooding surfaces (MFSs) are major seismic downlap surfaces associated with changes from retrogradational to progradational parasequence stacking patterns. Systems tracts are identified by their bounding surfaces and fining- (generally deepening) and coarsening- (generally shallowing) upward trends in cores and well-log stacking patterns. Our Miocene examples of sequences m5.4 (17.7–16.1 Ma) and m5.8 (20.1–19.2 Ma) illustrate how basic sequence stratigraphic techniques reveal higher-order sequences within Myr scale composite sequences. Our mid-Cretaceous examples from the New Jersey shelf provide a paleoshelf transect spanning the Great Stone Dome to the outer continental shelf to identify parasequences, sequences, and systems tracts. This sequence stratigraphic framework provides insights into Myr scale coeval depositional environments across the paleoshelf and reservoir continuity, and highlights the application of basic sequence stratigraphic criteria to reservoir-scale evaluation, not only for oil and gas resources, but also for carbon storage.

Attention to offshore prospects for geologic storage of carbon dioxide (CO 2 ) in the U.S. is required to address numerous large point sources located along the U.S. Atlantic Coast. Research is underway to develop a reliable method for screening candidate storage formations with the greatest potential for effective, permanent storage of CO 2 , and producing data-driven regional-scale estimates of the prospective CO 2 storage resource that exists offshore of the Mid-Atlantic U.S. This paper introduces the Mid-Atlantic U.S. Offshore Carbon Storage Resource Assessment project, describes the technical approach to achieve project goals, and presents preliminary results. The existing data set and challenges for data collection and analysis also are discussed.

The Mid-Atlantic U.S. Coastal Plain (New Jersey, Delaware, Maryland, and northern Virginia) contains thick (> 500 m) mid-Cretaceous sand–sandstone reservoirs confined by thick clay–shale confining units and thus has high potential for storage of CO 2 captured from nearby point sources. The predictability of the continuity of the reservoir and confining units can be improved by applying principles of sequence stratigraphy, including integration of lithostratigraphy, biostratigraphy, paleoenvironmental proxies, and a novel application of fluvial aggradation cycles (FACs). We evaluate the storage and confinement potential for the Lower Cretaceous Waste Gate Formation and mid-Cretaceous Potomac Formation/Group in New Jersey and Maryland, which we divide into three major reservoirs (Waste Gate-Potomac Unit I, Potomac Unit II, and Potomac Unit III). We use new core data to ground-truth well-logs and paleoenvironmental changes, sequence stratigraphic stacking patterns (including FACs), and pollen biostratigraphy to update previous well-log correlations in New Jersey and extend these correlations into deep holes in Maryland. While individual sand beds are typically local in extent, zones of sands are broadly correlative over distances of 60 km. These regionally traceable sand-prone zones should be useful for carbon storage. Cenomanian Potomac Unit III sands are relatively thick (∼ 70 m) in New Jersey, but generally thin (average of ∼ 50 m) into Maryland; they are near the updip limit for supercritical storage (800 m) in New Jersey and Maryland and may not be suitable due to updip migration above the supercritical level. Potomac Unit II sands (Albian Pollen Zone II) appear to be discontinuous and less suitable in both states. Potomac Unit I (Aptian Pollen Zone I) and Waste Gate Formation sands (?early Aptian to Berriasian pre-Pollen Zone I) are relatively thick (∼ 88–223 m and ∼ 81–288 m, respectively) and confined in New Jersey and appear to be widespread and continuous; the updip confinement of this reservoir in Maryland is less certain. Volume storage estimates for the Potomac I-Waste Gate in the Mid-Atlantic Coastal Plain are 8.4–33.5 Gt CO 2 , adequate to store CO 2 captured from 24–95 GW of natural gas generation for a century.

We present orbital-scale resolution (~10-kyr) benthic foraminiferal δ18O and δ13C records from the Kerguelen Plateau (Ocean Drilling Program [ODP] Sites 751 and 747) from 14.5-20.0 Ma spanning the Miocene climate optimum (MCO; 15-17 Ma). Our records fill a critical gap from ~17-18 Ma, a time when many other deep-sea records are affected by dissolution. We tested the fidelity of published magneto-biostratigraphic age models for these sites by astronomically tuning to the 405-kyr eccentricity cycle. A comparison of spectral estimates between the untuned and tuned records, as well as coherency with Laskar's (2004) eccentricity solution, revealed quasi-100-kyr cyclicity in δ18O and δ13C. There is only a weak signal associated with the 41-kyr obliquity cycle, likely due to the 10-kyr sampling limiting resolution. The δ18O variations point to persistent 405- and quasi-100-kyr modulations of temperature and sea-level changes through the early to middle Miocene as predicted by astronomical solutions, with changing dominance of the 100- and 41-kyr beat. Comparison of δ18O records with early to middle Miocene sequences from the New Jersey shelf, northeast Australian margin, Bahamas, and Maldives suggests that the dominant sea-level period preserved is the 1.2-Myr obliquity cycle, with sequence boundaries associated with δ18O increases or maxima. On the New Jersey margin, higher order sequences reflect the quasi-100-kyr eccentricity cycles as modulated by 405-kyr cycles. We suggest that “nesting” of stratigraphic cycles is a function of: 1) pervasive (though changing) Milankovitch forcing of global mean sea-level change; and 2) preservation that depends on sufficient sediment supply and accommodation.

We present new δ13C and δ18O records of surface (Morozovella and Acarinina) and thermocline dwelling (Subbotina) planktonic foraminifera and benthic foraminifera (Gavelinella, Cibicidoides, and Anomalinoides) during the Paleocene-Eocene Thermal Maximum (PETM) from Millville, New Jersey and compare them with three other sites located along a paleoshelf transect from the U.S. mid-Atlantic coastal plain. Our analyses show different isotopic responses during the PETM in surface versus thermocline and benthic species. Whereas all taxa record a 3.6-4.0 ‰ δ13C decrease associated with the carbon isotope excursion (CIE), thermocline dwellers and benthic foraminifera show larger δ18O decreases compared to surface dwellers. We consider two scenarios that can explain the observed isotopic records: 1) a change in the water column structure; and 2) a change in habitat or calcification season of the surface dwellers due to environmental stress (e.g., warming, ocean acidification, surface freshening, and/or eutrophication). In the first scenario, persistent warming during the PETM would have propagated heat into deeper layers and created a more homogenous water column with a thicker warm mixed layer and deeper, more gradual thermocline. We attribute the hydrographic change to decreased meridional thermal gradients, consistent with models that predict polar amplification. The second scenario assumes that environmental change was greater in the mixed layer forcing surface dwellers to descend into thermocline waters as a refuge or restrict their calcification to the colder seasons. Though both scenarios are plausible, similar δ13C responses recorded in surface, thermocline, and benthic foraminifera challenge mixed layer taxa migration.

Over the past decade, nitrogen (N) loads to Narragansett Bay have decreased by more than 50%. These reductions were, in large part, the direct result of multiple wastewater treatment facility upgrades to tertiary treatment, a process which employs N removal. Here we document ecosystem response to the N reductions and assess how the distribution of sewage N in Narragansett Bay has changed from before, during, and shortly after the upgrades. While others have observed clear responses when data were considered annually, our seasonal and regional comparisons of pre- and post-tertiary treatment dissolved inorganic nitrogen (DIN) concentrations and Secchi depth data, from bay-wide surveys conducted periodically from the early 1970s through 2016, resulted in only a few subtle differences. Thus we sought to use stable isotope data to assess how sewage N is incorporated into the ecology of the Bay and how its distribution may have changed after the upgrades. The nitrogen (δ(15)N) and carbon (δ(13)C) stable isotope measurements of particulate matter served as a proxy for phytoplankton, while macroalgae served as short-term integrators of water column bio-available N, and hard clams (Mercenaria mercenaria) as integrators of water column production. In contrast to other estuarine stable isotope studies that have observed an increased influence of isotopically lower marine N when sewage N is reduced, the opposite has occurred in Narragansett Bay. The tertiary treatment upgrades have increased the effluent δ(15)N values by at least 2‰. The plants and animals throughout Narragansett Bay have similarly increased by 1–2‰, on average. In contrast, the δ(13)C values measured in particulate matter and hard clams have declined by about the same amount. The δ(15)N results indicated that, even after the N-reductions, sewage N still plays an important role in supporting primary and secondary production throughout the Bay. However, the δ(13)C suggest that overall net production in Narragansett Bay has decreased. In the five years after the major wastewater treatment facilities came on-line for nutrient removal, oligotrophication has begun but sewage remains the dominant source of N to Narragansett Bay.

International audience; Shorelines are ephemeral features, yet many science problems cross this ever-moving boundary and require sampling on both its dry and wet sides. The logistics of working on land and at sea are distinct, such that funding agencies in many countries divide their research programs at the shoreline. Similarly, scientific drilling is split between the International Ocean Discovery Program (IODP) in the ocean and the International Continental Scientific Drilling Program (ICDP) on land. Here, we discuss three examples of drilling projects that effectively coordinated activities between IODP and ICDP and highlight the need for increasing cooperation and coordination across the shoreline. We end by casting an eye toward the future of scientific drilling, where truly amphibious projects are now possible.