Newark Basin Research Articles

Constraining Geogenic Sources of Boron Impacting Groundwater and Wells in the Newark Basin, USA

The Newark Basin comprises Late Triassic and Early Jurassic fluvio-lacustrine rocks (Stockton, Lockatong, Passaic, Feltville, Towaco, and Boonton Formations) and Early Jurassic diabase intrusions and basalt lava flows. Boron concentrations in private well water samples range up to 18,000 μg/L, exceeding the U.S. Environmental Protection Agency Health Advisory of 2000 μg/L for children and 5000 μg/L for adults. Boron was analyzed in minerals, rocks, and water samples using FUS-ICPMS, LA-ICP-MS, and MC ICP-MS, respectively. Boron concentrations reach up to 121 ppm in sandstone of the Passaic Formation, 42 ppm in black shale of the Lockatong Formation, 31.2 ppm in sandstone of the Stockton Formation, and 36 ppm in diabase. The δ11B isotopic values of groundwater range from 16.7 to 32.7‰, which fall within those of the diabase intrusion (25 to 31‰). Geostatistical analysis using Principal Component Analysis (PCA) reveals that boron is associated with clay minerals in black shales and with Na-bearing minerals (possibly feldspar and evaporite minerals) in sandstones. The PCA also shows that boron is not associated with any major phases in diabase intrusion, and is likely remobilized from the surrounding rocks by the intrusion-related late hydrothermal fluids and subsequently incorporated into diabase. Calcite veins found within the Triassic rock formations exhibit relatively elevated concentrations ranging from 6.3 to 97.3 ppm and may contain micro-inclusions rich in boron. Based on the available data, it is suggested that the primary sources of boron contaminating groundwater in the area are clay minerals in black shales, Na-bearing minerals in sandstone, diabase intrusion-related hydrothermal fluids, and a contribution from calcite veins.

Characterization and Origin of Basalt-Derived Carnelian in the Mesozoic Newark Basin, New Jersey, USA

Carnelian occurs locally in New Jersey in the Newark basin as medium- to coarse-size pebbles in fluvial gravel and alluvium and colluvium formed from erosion of Lower Jurassic Preakness Basalt. Vesicles and molds of glauberite are preserved on lower surfaces and botryoidal textures on the upper surfaces of some pieces. The microstructure consists of length-fast chalcedony characterized by parallel fibrous bundles overlain by repetitive, wavy extinction bands. Only peaks of ɑ-quartz and minor moganite are recognized in X-ray diffraction patterns. Carnelian contains 97–98 wt.% SiO2, ~1.0 wt.% Fe2O3, and 1.0–1.4 wt.% LOI; other major elements are <0.1 wt.%. Trace element abundances are low except for Y, Nb, Ta, W, Th, and U. Rare earth element (REE) patterns display heavy REE enrichment and large negative Eu anomalies. Most trace elements were mobilized from Proterozoic sources, whereas Si was likely derived from the alteration of basaltic glass in the Preakness. Carnelian δ18OVSMOW values are high and range from +18.3 to +31.2‰, comparable to global occurrences of volcanic rock-derived chalcedony. We propose that carnelian precipitated in the first Preakness flow from the mixing of hydrothermal fluid with meteoric water under conditions of low temperature (20–80 °C) and neutral to slightly alkaline pH.

Detrital zircon and apatite U-Pb provenance and drainage evolution of the Newark Basin during progressive rifting and continental breakup along the Eastern North American Margin, USA

Abstract Mesozoic rift basins of the Eastern North American Margin (ENAM) span from Florida in the United States to the Grand Banks of Canada and formed during progressive extension prior to continental breakup and the opening of the north-central Atlantic. The syn-rift strata from all the individual basins, lumped along the entire margin into the Newark Supergroup, are dominated by fluvial conglomerate and sandstone, lacustrine siltstone, mudstone, and abundant alluvial conglomerate and sandstone lithofacies. Deposition of these syn-rift sedimentary rocks was accommodated in a series of half grabens and subsidiary full grabens situated within the Permo-Carboniferous Appalachian orogen. The Mesozoic ENAM is commonly depicted as a magma-rich continental rift margin, with magmatism (Central Atlantic magmatic province [CAMP]) driving continental breakup. However, the southern portion of the ENAM shows evidence of magmatic breakup (e.g., seaward-dipping reflectors), and rifting and crustal thinning appeared to start ~30 m.y. prior to CAMP emplacement in the Jurassic. This study provides extensive new detrital zircon and apatite U-Pb provenance data to determine the provenance and reconstruct the paleodrainages of the Newark Basin during progressive rifting and magmatic breakup and the implications for the overall rift configuration and asymmetry during progressive rifting along the ENAM rift margin. Detailed new detrital zircon (N = 21; n = 3093) and apatite (N = 4; n = 559) U-Pb results from sandstone outcrop and core samples from the Newark Basin indicate a distinct provenance shift, with relatively older Carnian syn-rift strata predominately sourced from the hanging wall of the basin bounding fault in the east while relatively younger Norian strata were regionally sourced from both the hanging wall and footwall. The syn-rift strata at the Triassic-Jurassic boundary were sourced from the hanging wall before a transition to local footwall terranes. These results suggest two major provenance changes during progressive rifting—the first occurring during Carnian crustal necking and rift flank uplift as predicted by recent numerical models and the second occurring at the onset of the Jurassic due to regional and local thermal uplift during CAMP magmatism as seen along other magma-rich margins, such as the North Atlantic and the southern portion of the South Atlantic margin.

Late Triassic sedimentary records reveal the hydrological response to climate forcing and the history of the chaotic Solar System

The hydrological change plays a vital role in regulating Earth's surface systems. However, understanding past hydrological variations on land is hindered by difficulties in dating and correlating continental strata, and the perceived incompleteness of terrestrial sedimentary successions. Here, we calibrate the astronomical time scale of an Upper Triassic lake sediment succession at St. Audrie's Bay (UK) using recently proposed statistical tuning approaches. A novel statistical completeness evaluation confirms that an optimal correlation of the astronomically calibrated Upper Triassic magnetostratigraphy can be determined between St. Audrie's Bay and well-studied reference sections in the Newark Basin (USA) and Jameson Land Basin (Greenland). Reconstructed lake level changes at St. Audrie's Bay were in-phase with those in the Newark Basin (deposited at a similar tropical paleolatitude), but in anti-phase with those in the high-latitude Jameson Land Basin – a pattern also supported by paleoclimate modeling. A ∼1.8 million-year cyclicity paced hydrological changes in these basins, and represents the fingerprint of chaotic behavior of the Solar System.

Unravelling the fluid flow evolution and precipitation mechanisms recorded in calcite veins in relation to Pangea rifting–Newark Basin, USA

Calcite veins hosted in the Triassic Stockton, Lockatong and Passaic formations of the Newark Basin are investigated to reconstruct the fluid evolution. To constrain the parameters of calcite precipitation, a microthermometry study was carried, which reveals precipitation of calcite from a low to moderate saline H2O-NaCl fluid (0.4 to 13.2 wt% NaCl equiv.) under low to moderate hydrothermal (137 °C to 232 °C) conditions. This fluid composition is interpreted to reflect mixing between a deep basement-derived heated diluted fluid and relatively low to moderate saline diagenetic formation waters hosted in the different Triassic formations. Carbon and strontium isotope analysis on the vein calcites suggests that these elements are derived from the pre-Triassic basement and the sedimentary cover through fluid-rock interactions. The aforementioned geochemical findings are supported by Rare Earth Elements and Yttrium (REY) systematics and oxygen isotope data.The Late Triassic extensional activity and gravity-driven fluid flow mechanism facilitated the infiltration of meteoric waters to deeper lithostratigraphic units (i.e., Precambrian-Paleozoic basement-Triassic Stockton Formation) where they became heated. In response to the extensional tectonics, the deep-seated hydrothermal basement-derived diluted fluids migrated upward along the tectonic-related fractures and the major faults to upper shallow crustal levels. Here, the heated, diluted meteoric waters were mixed with low, moderately saline, and relatively cooler formation waters, leading to calcite precipitation. The pH increase is suggested to be a contributing factor in the precipitation of calcite.

Microstructural Evidence for the Fluid Dynamical Behaviour in Vertically and Laterally Propagated Dykes of the British and Irish Paleogene Igneous Province

AbstractA detailed study of dykes from the British and Irish Paleogene Igneous Province, with the Birdsboro dyke of the Newark Basin, USA, as a comparison, shows that microstructures vary systematically as a function of distance from the parent igneous complex. Proximal dykes (both those that propagated vertically and the proximal exposures of laterally propagated dykes) have invariant plagioclase grain shape and a generally coarse grain size, consistent with sustained convection during solidification. In contrast, distal exposures of laterally propagated dykes are generally finer grained and have a systematic spatial variation of plagioclase grain shape indicative of in situ nucleation and growth on inwards-propagating solidification fronts. These differences are argued to be a consequence of a systematic progression in the level of exposure along the dyke swarm, due to differential uplift and erosion associated with underplating of the NW parts of the British Isles. Convection in vertically propagated dykes is likely to occur throughout the full height of the intrusion, but is confined to the wider regions of laterally propagating dykes, with little or no convection in their narrower upper regions. There are generally no marginal reversals in the variation of plagioclase shape in dykes, indicative of relatively rapid emplacement of vertical intrusions compared to sills of comparable thickness. Comparison of plagioclase grain shape in dykes with invariant grain shape with that in bodies for which solidification is inferred to have occurred in marginal solidification fronts may be used to constrain the average width of the convective system. The Birdsboro dyke is anomalously fine grained compared to other dykes with invariant plagioclase grain shape, indicating that a coarse grain size is not a universal characteristic of convecting dykes: the relatively fine grain size is suggestive of a high crystal load, perhaps due to it forming part of an extensive sill complex.

Planetary chaos and inverted climate phasing in the Late Triassic of Greenland

Sedimentological records provide the only accessible archive for unraveling Earth’s orbital variations in the remote geological past. These variations modulate Earth’s climate system and provide essential constraints on gravitational parameters used in solar system modeling. However, geologic documentation of midlatitude response to orbital climate forcing remains poorly resolved compared to that of the low-latitude tropics, especially before 50 Mya, the limit of reliable extrapolation from the present. Here, we compare the climate response to orbital variations in a Late Triassic midlatitude temperate setting in Jameson Land, East Greenland (∼43°N paleolatitude) and the tropical low paleolatitude setting of the Newark Basin, with independent time horizons provided by common magnetostratigraphic boundaries whose timing has been corroborated by uranium-lead (U-Pb) zircon dating in correlative strata on the Colorado Plateau. An integrated cyclostratigraphic and magnetostratigraphic age model revealed long-term climate cycles with periods of 850,000 and 1,700,000 y ascribed to the Mars–Earth grand orbital cycles. This indicates a 2:1 resonance between modulation of orbital obliquity and eccentricity variations more than 200 Mya and whose periodicities are inconsistent with astronomical solutions and indicate chaotic diffusion of the solar system. Our findings also demonstrate antiphasing in climate response between low and midlatitudes that has implications for precise global correlation of geological records.

A Borehole Test for Chlorinated Solvent Diffusion and Degradation Rates in Sedimentary Rock

AbstractWe present a new field measurement and numerical interpretation method (combined termed “test”) to parameterize the diffusion of trichloroethene (TCE) and its biodegradation products (DPs) from the matrix of sedimentary rock. The method uses a dual‐packer system to interrogate a low‐permeability section of the rock matrix adjacent to a previously contaminated borehole and uses the borehole monitoring history to establish the pretest condition. TCE and its DPs are removed from the groundwater between the packers at the onset of the testing. The parameters estimated by fitting a radial diffusion model to the concentration history and borehole concentration data, also termed back diffusion, are the tortuosity factor and sorption coefficients of TCE and DPs in the rock matrix and the TCE and DP biodegradation rate coefficients in the borehole. We demonstrate the equipment design and the interpretive method using a borehole accessing the gray mudstone at a TCE contaminated site in the Newark Basin. In this test, both nonreactive (bromide) and reactive (trichlorofluoroethene) tracers are used to constrain the estimated parameters; however, the bromide tracer was not needed to estimate the parameters in this test. The parameters estimated from the field test are consistent with values measured independently in laboratory experiments using field samples of similar lithology. From the interpretation, we compute the TCE and DP concentration distributions in the rock matrix prior to the test to illustrate how the results can be used to enhance understanding of contaminant distribution in the rock matrix.

Sedimentary noise modeling of lake-level change in the Late Triassic Newark Basin of North America

Two different hypotheses, glacioeustasy and groundwater aquifer eustasy, have been proposed to explain short-term, high-amplitude sea-level oscillations during past greenhouse-dominated intervals. However, the veracity of aquifer eustasy on long-term, high amplitude sea level has never been rigorously tested. We evaluate these competing hypotheses using the objective approach of sedimentary noise modeling for lake-level reconstruction. Statistical tuning and astronomical calibration of paleoclimate and paleoenvironment proxies (depth rank, rock color, gamma ray, and sonic velocity) from the lacustrine Newark Basin enable the construction of a 31.55-Myr long astronomical time scale (ATS) for the Late Triassic that is comparable to the classic Newark ATS previously presented. Using this timescale, sedimentary noise modeling in the lacustrine Newark Basin is carried out through the Late Triassic. Lake level fluctuations reconstructed by sedimentary noise modeling and principal component analysis reveal that million-year scale lake-level variations were linked to astronomical forcing with periods of ~3.3 Myr, ~1.8 Myr, and ~1.2 Myr. Our results demonstrate that astronomical forcing, as a driver of groundwater dynamics, may have had an impact on global sea-level changes during the Late Triassic. This study thus emphasizes the importance of high-resolution, objective reconstruction of sea- and lake-levels for further testing the hypotheses of glacioeustasy and aquifer eustasy under warm conditions. • We reconstruct high-resolution lake-level changes in the Late Triassic. • Long-period astronomical forcing drove lake-level and sea-level variations. • Continental groundwater could have an impact on global sea-level fluctuations. • High-resolution, objective reconstruction of lake- and sea-levels is key to test aquifer eustasy versus glacioeustasy.

Widespread elevated iridium in Upper Triassic\u2013Lower Jurassic strata of the Newark Supergroup: implications for use as an extinction marker

Anomalous levels of iridium in sedimentary strata are associated with mass extinction events caused by impact events. In the case of the end-Triassic extinction event, the anomalies as well as the extinctions are linked to the eruption of the Central Atlantic Magmatic Province (CAMP) flood basalts. We report new data on concentrations of iridium in continental strata of the Fundy, Deerfield, Hartford and Newark basins, both above and below the oldest CAMP flows in these basins, that demonstrate that these anomalies are more common than previously known. We conclude that the enrichments were at least in some instances likely derived locally by concentration due to leaching directly from the lavas into sediments proximal to the CAMP flows due to post-eruptive hydrothermal activity. In other instances, the enrichments likely record the global fallout of aerosols and/or ash particles during the eruptions of the CAMP basalts. The common association of the highest levels of enrichment with organic matter suggests either redox control or stabilization by formation of organometallic complexes following post-eruptive redistribution. These findings demonstrate the importance of considering the distribution and magnitude of iridium anomalies in considering the source of the iridium and possible extinction mechanisms.

"Short" or "long" Rhaetian ? Astronomical calibration of Austrian key sections

The establishment of the Late Triassic time scale has given rise to considerable controversy, particularly regarding the Rhaetian duration and the inferred absolute age models. In this respect the astronomical polarity time scale (APTS) established from the continental successions of the Newark Basin (eastern North America) is considered as a reference record, although its completeness is questioned. Numerous magnetostratigraphic correlation schemes have been proposed between the APTS and biostratigraphically well-constrained Tethyan marine sections. This has led to two main contrasting options: a “short” Rhaetian duration (about 4–5 myr), and a “long” one (about 8–9 myr). Astronomical calibration of the Tethyan Rhaetian and estimate of its duration is necessary to help advance this debate. We have undertaken a cyclostratigraphic analysis of a Rhaetian composite record built from four overlapping Austrian reference sections. Magnetic susceptibility variations of the 131.5 m thick record are astronomically paced by the precession and 405-kyr orbital eccentricity cycles. 405-kyr orbital tuning allows to establish a floating time scale, and thus to suggest a minimum duration of 6.69 myr of the Rhaetian stage. Given the well-established radioisotopic age of the Rhaetian-Hettangian boundary of 201.36 Ma, an age no younger than 208.05 Ma for the Norian-Rhaetian boundary can be proposed. This result will contribute to the refinement of the Late Triassic time scale, but it does not solve the long-standing debate on bio-magnetostratigraphic correlations between the continental Newark APTS and the Tethyan marine sections, nor the question of the completeness of the Rhaetian Newark Basin. (Less)

Rhaetian (Late Triassic) Milankovitch Cycles in the Tethyan Dachstein Limestone and Laurentian Passaic Formation Linked by the g2-g5 Astronomical Metronome

Milankovitch cycles have long been suspected of having been recorded in the shallow marine Lofer cyclothems of the Rhaetian Dachstein Limestone of the European Northern and Southern Calcareous Alps. However, sufficient evidence has not yet been forthcoming to make a compelling case for Milankovitch control on the cyclothems. At the same time, there is overwhelmingly strong evidence that Milankovitch cycles were influencing the paleoclimates of Rhaetian Laurentia and the wet-dry playa lake deposits of the Passaic Formation (Newark Basin, USA). The strongest cycles in these deposits, the McLaughlin cycles, have been linked to the metronomic g2-g5, or 405 kyr orbital eccentricity cycle. Thus, Milankovitch cycles were operating throughout the Rhaetian, and being global in nature, likely played a role in the genesis of the coeval Lofer cyclothems. The Dachstein Limestone in the Julian Alps, relatively undisturbed by tectonics, exhibits strong Milankovitch-like cyclicity, including evidence for g2-g5 cycling. The shallow marine Dachstein and continental Passaic formations provide evidence for complementary forcing mechanisms and active aquifer-limno-eustasy: low sea level in Lofer exposure facies is reflected in wet Passaic playa lake deposits, and high sea level in Lofer subtidal facies in dry Passaic playa lake deposits. The Dachstein and Passaic formations are further linked by the g2-g5 metronome; a provisional correlation is proposed, subject to future validation by additional, as yet undeveloped chronostratigraphic constraints.

Trace fossils in fluvial deposits of the uppermost Stockton Formation (Late Triassic), Newark Basin, New Jersey

Fluvial deposits of the uppermost Stockton Formation (Late Triassic), Newark Basin, west-central New Jersey have yielded an assemblage of trace fossils. Dominated by burrows, specimens include Cochlichnus anguineus, Helminthoidichnites tenuis, Planolites beverleyensis, Scoyenia gracilis, Spongeliomorpha carlsbergi, Treptichnus bifurcus, Treptichnus pollardi, plant remains, and an undetermined vertebrate trace fossil. The assemblage belongs to the Scoyenia ichnofacies. On the basis of stratification and primary sedimentary structures, the beds are interpreted as deposits in a meandering stream environment. Larval insects, wormlike forms, and arthropods are probably responsible for most of the animal traces in wet or moist channel, floodplain, and point bar sediments subject to subaerial exposure.

Reservoir and sealing properties of the Newark rift basin formations: Implications for carbon sequestration

The Newark Basin is one of the major Mesozoic rift basins along the U.S. Atlantic coast evaluated for carbon dioxide (CO2) storage potential. Its geologic setting offers an opportunity to assess both the traditional reservoir targets, e.g., fluvial sandstones, and less traditional options for CO2 storage, e.g., mafic intrusions and lavas. Select samples from the basal, predominantly fluvial, Stockton Formation are characterized by relatively high porosity (8%–18%) and air permeability (0.1–50 mD), but borehole hydraulic tests suggest negligible transmissivity even in the high-porosity intervals, emphasizing the importance of scale in evaluating reservoir properties of heterogeneous formations. A stratigraphic hole drilled by TriCarb Consortium for Carbon Sequestration in the northern basin also intersected numerous sandstone layers in the predominantly lacustrine Passaic Formation, characterized by core porosity and permeability up to 18% and 2000 mD. However, those layers are shallow (predominantly above 1 km in this part of the basin) and lack prominent caprock layers above. The mudstones in all three of the major sedimentary formations (Stockton, Lockatong, and Passaic) are characterized by a high CO2 sealing capacity — evaluated critical CO2 column heights exceed several kilometers. The igneous options are represented by basalt lavas, with porous flow tops and massive flow interiors, and a crystalline but often densely fractured Palisade Sill. The Newark Basin basalts may be too shallow for sequestration over most of the basin's area, but many other basalt flows exist in similar rift basins. Abundant fractures in sedimentary and igneous rocks are predominantly closed and/or sealed by mineralization, but stress indicators suggest high horizontal compressional stresses and strong potential for reactivation. Overall, the basin potential for CO2 storage appears low, but select formation properties are promising and could be investigated in the Newark Basin or other Mesozoic rift basins with similar fill but a different structural architecture.

Hydraulic Tomography: 3D Hydraulic Conductivity, Fracture Network, and Connectivity in Mudstone.

We present the first demonstration of hydraulic tomography (HT) to estimate the three-dimensional (3D) hydraulic conductivity (K) distribution of a fractured aquifer at high-resolution field scale (HRFS), including the fracture network and connectivity through it. We invert drawdown data collected from packer-isolated borehole intervals during 42 pumping tests in a wellfield at the former Naval Air Warfare Center, West Trenton, New Jersey, in the Newark Basin. Five additional tests were reserved for a quality check of HT results. We used an equivalent porous medium forward model and geostatistical inversion to estimate 3D K at high resolution (K blocks <1 m3 ), using no strict assumptions about K variability or fracture statistics. The resulting 3D K estimate ranges from approximately 0.1 (highest-K fractures) to approximately 10-13 m/s (unfractured mudstone). Important estimated features include: (1) a highly fractured zone (HFZ) consisting of a sequence of high-K bedding-plane fractures; (2) a low-K zone that disrupts the HFZ; (3) several secondary fractures of limited extent; and (4) regions of very low-K rock matrix. The 3D K estimate explains complex drawdown behavior observed in the field. Drawdown tracing and particle tracking simulations reveal a 3D fracture network within the estimated K distribution, and connectivity routes through the network. Model fit is best in the shallower part of the wellfield, with high density of observations and tests. The capabilities of HT demonstrated for 3D fractured aquifer characterization at HRFS may support improved in situ remediation for contaminant source zones, and applications in mining, repository assessment, or geotechnical engineering.

Effects of pH on redox proxies in a Jurassic rift lake: Implications for interpreting environmental records in deep time

Abstract It is widely agreed that the Earth’s atmosphere and oceans have undergone major redox changes over the last 2.5 billion years. However, the magnitude of these shifts remains a point of debate because it is difficult to reconstruct concentrations of dissolved O2 from indirect proxies in sedimentary archives. In this study, we show that an additional complicating factor that is rarely considered may be the pH of the water column. We analyzed rock samples from the early Jurassic Towaco Formation in the Newark basin (eastern USA), comprising deposits of a rift lake that became temporarily redox stratified. New biomarker evidence points to increasingly saline aquatic conditions during the second half of the lake’s history. Salinity stratification likely induced redox stratification, consistent with the disappearance of macrofauna at this time. Distinctive lipid biomarker assemblages and stable nitrogen isotope data support previous mineralogical indications that the lake was alkaline (pH ≥ 9) during its saline episode. Despite the biomarker and macrofaunal evidence for anoxia, ratios of Fe/Al and FeHR/FeT show only small to no enrichments in the anoxic horizon compared to oxic facies in the same section – counter to what is commonly observed in anoxic marine settings. Molybdenum, As, V, U and to some degree Cd show enrichments in the anoxic interval, whereas Co, Ni, Cu, Zn and Cr do not. These patterns are most parsimoniously explained by differential pH effects on the solubility of these elements. Extrapolating from these observations in lacustrine strata, we speculate that a secular increase in seawater pH over Earth’s history as recently proposed may have helped modulate the magnitude of trace metal enrichments in marine shales, although other factors such as atmospheric and oceanic redox likely dominated the observed enrichment patterns. Further, a decrease in the solubility of ferrous iron, a major O2 sink, with increasing pH may have contributed to ocean oxygenation. In summary, our results highlight the potential importance of pH in influencing global biogeochemical cycles for multiple elements, including the ancient nitrogen isotope record.

Profile of Paul E. Olsen

Geologist Paul E. Olsen follows a simple guiding principle: obtain information from the geological record that is not available from other sources. Doing so has enabled Olsen, a professor of earth and environmental sciences at the Lamont–Doherty Earth Observatory of Columbia University (LDEO), to illuminate the history of the Solar System and evolution of continental ecosystems. Olsen, who was elected to the National Academy of Sciences in 2008, recovered a climate cyclicity record spanning 30 million years and discovered the largest North American vertebrate fossil assemblage at the Triassic–Jurassic boundary. His latest project is The Geological Orrery, a network of early Mesozoic geological records of orbitally paced climate that could lead to fundamental insights into physical processes of the Solar System. Paul E. Olsen. Image courtesy of Kevin Krajick (Columbia University, New York). Olsen was born in New York City in 1953, but after a series of moves he and his family settled in Livingston, New Jersey. Olsen says, “I was one of those awkward kids who knew all the names of the dinosaurs described in children’s and young readers’ books of the 1950s and was happy to tell anyone all about them.” When he learned that another Livingston resident, Silvio Crespo, Jr., found dinosaur footprints in the summer of 1968 at nearby Riker Hill on what was then the Roseland Quarry, he and friend Anthony Lessa hiked 1.5 miles to the site. There, they met amateur paleontologist Robert Salkin, who introduced them to vertebrate paleontologist Donald Baird, then at Princeton University, and Bobb Schaeffer, a curator and Triassic fish expert at the American Museum of Natural History. Baird facilitated a meeting with Princeton sedimentologist Franklyn Van Houten, who had interpreted the alternating gray and red layers of older strata in the Newark Basin as being paced by variations in …

Hydrocarbon Potential of the Triassic Lacustrine Source Rocks in the Newark Basin, USA

This study investigates the hydrocarbon potential of the organic matter-rich Triassic rocks of the Newark basin in the USA. The development of anoxic conditions during the Late Triassic led to the accumulation and preservation of the organic matter during the deposition of the Lockatong formation in a lacustrine setting. The total organic carbon (TOC) values of the black shale samples from the Nursery and Titusville cores of this formation range from 0.50 to 2.72% (avg.=1.2%), indicating a fair to good source rock. On the Hydrogen Index (HI) vs the Oxygen Index (OI) diagram, the studied samples plot at the end of the evolutionary paths of kerogen types I, II, and III. This indicates that the organic matter is overmature and is in the dry gas window. This degree of maturity is also consistent with the Tmax values ranging from 506°C to 547°C and is confirmed by published vitrinite reflectance values (%Ro) which vary between 1.95 and 2.69%. This overmaturity is the result of an active subsidence during the Late Triassic-early Jurassic in relation with the reactivation with the deep-seated regional NE-SW-trending faults. Although the overmaturity of the organic matter renders the identification of the type of organic matter difficult, the organic matter is likely kerogen II-III type. On the basis of the available data, it is concluded that this formation has no generative liquid hydrocarbon potential.

Colorado Plateau Coring Project, Phase I (CPCP-I): a continuously cored, globally exportable chronology of Triassic continental environmental change from western North America

Abstract. Phase 1 of the Colorado Plateau Coring Project (CPCP-I) recovered a total of over 850 m of stratigraphically overlapping core from three coreholes at two sites in the Early to Middle and Late Triassic age largely fluvial Moenkopi and Chinle formations in Petrified Forest National Park (PFNP), northeastern Arizona, USA. Coring took place during November and December of 2013 and the project is now in its post-drilling science phase. The CPCP cores have abundant detrital zircon-producing layers (with survey LA-ICP-MS dates selectively resampled for CA-ID-TIMS U-Pb ages ranging in age from at least 210 to 241 Ma), which together with their magnetic polarity stratigraphy demonstrate that a globally exportable timescale can be produced from these continental sequences and in the process show that a prominent gap in the calibrated Phanerozoic record can be filled. The portion of core CPCP-PFNP13-1A for which the polarity stratigraphy has been completed thus far spans ∼215 to 209 Ma of the Late Triassic age, and strongly validates the longer Newark-Hartford Astrochronostratigraphic-calibrated magnetic Polarity Time-Scale (APTS) based on cores recovered in the 1990s during the Newark Basin Coring Project (NBCP). Core recovery was ∼100 % in all holes (Table 1). The coreholes were inclined ∼60–75∘ approximately to the south to ensure azimuthal orientation in the nearly flat-lying bedding, critical to the interpretation of paleomagentic polarity stratigraphy. The two longest of the cores (CPCP-PFNP13-1A and 2B) were CT-scanned in their entirety at the University of Texas High Resolution X-ray CT Facility in Austin, TX, and subsequently along with 2A, all cores were split and processed at the CSDCO/LacCore Facility, in Minneapolis, MN, where they were scanned for physical property logs and imaging. While remaining the property of the Federal Government, the archive half of each core is curated at the NSF-sponsored LacCore Core Repository and the working half is stored at the Rutgers University Core Repository in Piscataway, NJ, where the initial sampling party was held in 2015 with several additional sampling events following. Additional planned study will recover the rest of the polarity stratigraphy of the cores as additional zircon ages, sedimentary structure and paleosol facies analysis, stable isotope geochemistry, and calibrated XRF core scanning are accomplished. Together with strategic outcrop studies in Petrified Forest National Park and environs, these cores will allow the vast amount of surface paleontological and paleoenvironmental information recorded in the continental Triassic of western North America to be confidently placed in a secure context along with important events such as the giant Manicouagan impact at ∼215.5 Ma (Ramezani et al., 2005) and long wavelength astronomical cycles pacing global environmental change and trends in atmospheric gas composition during the dawn of the dinosaurs.

Pore structure, gas storage and matrix transport characteristics of lacustrine Newark shale

Abstract Shale gas production in the U.S. fuelled research activities in unconventional reservoir rock characterization. Most studies focused on organic-rich shales of marine origin, while disregarding lacustrine sequences. In this study, thirteen lacustrine shale samples from the Newark Basin, NJ, USA are comprehensively characterised in terms of pore structure, gas storage and matrix transport characteristics. These thermally overmature (VRr 1.4–2.7%) shales have a Na-rich, heterogeneous mineralogy with TOC contents of up to 3.6%. Methane sorption capacity and pore structure parameters as identified with low-pressure N2 physisorption (microporosity, BET surface area) are neither interrelated with each other nor with any shale components (e.g. clay content, TOC). In contrast, porosity shows a positive correlation with TOC content, which is also typical for many thermally overmature marine shale sequences. Correspondingly, porosity and TOC positively correlate to bedding parallel matrix permeability coefficients (between 2 and 80 nD at 40 MPa effective stress). In contrast, permeability coefficients perpendicular to bedding are two to three orders of magnitude lower. Compared to previous studies on marine lithotypes, Newark shales have rather poor gas storage properties with average He-porosities of 2.3% and average methane sorption capacities of 0.047 mmol g−1.