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The Norian–Rhaetian boundary (Late Triassic) represents an important precursor extinction event to the end- Triassic mass extinction, but the biotic and geochemical shifts are not well-understood due to poor stratigraphic constraints. Here we examine the microfossil record for metazoans and protists on a Panthalassan carbonate ramp (Gabbs Formation, Nevada, U.S.A.) during the late Norian to mid-Rhaetian, and correlate changes in these assemblages with macrofossil shifts and geochemical data (strontium and carbon isotopes). In the latest Norian, demosponge spicules represent a small proportion of shallow marine biosediments. Demosponges are joined in the earliest Rhaetian by increasingly abundant hypersilicified sponge spicules and silica-limited hexactinellid sponge spicules synchronous with a negative strontium isotope excursion indicating increased hydrothermal or volcanic activity. Common carbonate microfossils such as echinoderm ossicles and ostracods are typically silicified in these deposits as well, suggesting increased silicic porewater. The source for increased dissolved silica in shallow marine systems is suggested to be hydrothermal vent degassing, likely associated with increased tectonic rifting activity. Mid-Rhaetian microfossil assemblages exhibit evidence for intermitted anoxia in reducing conditions, supporting a scenario in which environmental stress was a prolonged feature of much of the Rhaetian Stage, rather than a short-term event in the terminal Rhaetian. While there is no marine sedimentary record of volcanism recognized for this interval, biosedimentary assemblages may serve as proxies for geochemical conditions associated with rifting. 

In the South Island of Aotearoa (New Zealand), the preservation of biogenic carbonate in Late Triassic sedimentary rocks is rare to non-existent; however, differential preservation modes between common phyla are commonly observed and serve to elucidate the stratigraphic and diagenetic history of these often poorly- exposed immature sandstone units. The Taringatura Group sandstones from Southland and Otago range from sandy siltstones to silty arkosic sandstones that commonly host molluscan and brachiopod macrofossils as well as rare echinoderms, bryozoans, and foraminifera. Additionally, there is a hypothesized unconformity between the lower Oretian and Otamitan age (227.7–217.0 Ma) and the overlying Warepan age (217–208.5 Ma) deposits indicated by an abrupt change in composition, grain size, and fossil assemblage. Molluscs from the Oretian and Otamitan deposits exhibit fine-detail preservation on external and internal molds. Thin-shelled taxa, such as Halobia, exhibit some shell replacement by clay minerals, likely from the dissolution of feldspars in the surrounding rock. Conversely, larger and thicker-shelled brachiopods and bivalves such as Manticula and Hokonuia do not present as casts. When preserved, foraminifera and rare bryozoans are typically silicified. The overlying Warepan sandstone beds frequently contain fossils of the bivalve Monotis which exhibit a similar preservation style to older molluscs, though lacking clay minerals. Presently, the fossiliferous Taringatura sandstones exhibit low porosity and low permeability, as is expected from the subsequent compaction of sandstones after burial. However, the dissolution of biogenic carbonate implies a past permeability. The presence of clay minerals in Oretian and Otamitan fossils may indicate a period of subaerial exposure and infiltration of meteoric water prior to the deposition of Warepan units. Notably, clay replacement occurs more frequently in the thinnest fossils. Original carbonate material may have persisted for longer in the more robust taxa, allowing them to resist most deformation from compaction prior to the final loss of carbonate. Differential diagenesis of biogenic carbonates supports the existence of a significant unconformity between Otamitan and Warepan units in the Taringatura sandstones. 

Late Triassic marine macrofaunal assemblages of Aotearoa (New Zealand) exhibit remarkably low diversity, high endemism, and synchronous faunal turnover, and present a complicated array of bottom-water oxygenation indicators. Here we present the results of three bulk sampling campaigns representing marine communities across both the North and South Islands. Four biofacies are present, beginning with Halobia biofacies in the Oretian (lower Norian). The Otamitan (middle Norian) deposits are characterized by two successive biofacies, the Manticula/Hokonuia biofacies and the high diversity brachiopod biofacies of the upper Otamitan. The Warepan (upper Norian) deposits are recognized by the Monotis biofacies. The four biofacies persist across different regions, displaying nearly identical turnover events despite sedimentological variations. However, the bivalve and brachiopod genera exhibit differential shell bed-forming capabilities in different regions. Only the bivalve Monotis was observed in dense shell beds in all three regions sampled. In the northernmost region sampled (including Kiritehere Beach), shell beds are the primary presentation for fossils irrespective of the taxa. We present a comparison of the sedimentological characteristics between shell bed and non-shell bed deposits. Large and/or inflated bivalves are not uncommon, but essentially no burrowing organisms are present. These findings provide crucial insights into the dynamic nature of Triassic marine ecosystems, shedding light on the paleontological diversity patterns and ecological structure of high-latitude systems during hot-house intervals. The persistence of the same biofacies over a broad spatial extent emphasizes the strong influence of regional environmental conditions on the establishment and maintenance of marine communities. 

Two recently discovered vertebrae collections from the Gabbs Formation in New York Canyon, Nevada, USA are among the first Late Triassic pistosauroid fossils reported from North America. Pistosauroidea were a group of long-necked secondarily aquatic reptiles that belong to the clade sauropterygia. Pistosauroids first evolved in the Triassic Period but later became an integral part of the Mesozoic marine ecosystem as the iconic plesiosaurs during the Jurassic and Cretaceous Periods. Our findings include a single small centrum from near the Triassic/Jurassic boundary and a block of similarly sized associated vertebrae from the early Rhaetian. The vertebrae exhibit a uniquely pistosauroid external morphology. The centrum is antero-posteriorly narrow but dorso-ventrally tall with gently amphicoelous faces. The histology revealed through micro-CT scanning, is also diagnostically pistosauroid. In sagittal cross-section, a denser layer of bone is visible along the faces of the centrum, while a unique V-shaped texture extending from the base of the neural canal is visible in transverse cross-section. The New York Canyon locality has long been renowned as a reference section for the Late Triassic and Triassic/Jurassic boundary but has only recently become a focus for vertebrate research. The Gabbs Formation at this locality is a relatively shallow marine environment and ranges from mid ramp to inner ramp. Vertebrate material has been noted throughout New York Canyon, nearly all of which has been identified as ichthyosaur, but these discoveries have shown the potential for the area as an important site for Late Triassic sauropterygians which have a poor record globally and were previously unknown from North America. Despite the limited nature of this new material, it is significant in providing evidence of the presence of pistosauroids in the Late Triassic of Eastern Panthalassa and helps fill in the exceptionally sparse history of sauropterygians in the Triassic of cordilleran North America. 

Sections of the Gabbs Formation exposed near New York Canyon, Nevada, have long been recognized as important sites for Late Triassic and Early Jurassic stratigraphy, and the Norian-Rhaetian parts of these sections continue to be important for defining this boundary (NRB). The two candidate sections for the base of the Rhaetian are in Tethys; both sections utilize the first occurrence of the conodont species Misikella posthernsteini as a proxy for the boundary. Although not a candidate section, data from New York Canyon will help to determine the most suitable position for the NRB, especially in Panthalassa. Previous reports of conodonts from New York Canyon recognized a fauna with Mockina englandi, Mo. bidentata and morphotypes of Mo. mosheri in the Nun Mine Member, below isolated occurrences of Zieglericonus rhaeticum and Mi. posthernsteini in the Mount Hyatt and Muller Canyon members. The first occurrence of Mi. posthernsteini in the section occurs well above the first occurrence of Rhaetian ammonoids (Paracochloceras amoenum) and together with late Rhaetian radiolarians. It is also above excursions in Sr- and C-isotopes, both of which correlate with Tethyan NRB excursions. Therefore, the NRB has previously been placed much lower in North America than Tethys, at the first occurrences of the radiolarian Proparvicingula moniliformis and the conodont Mo. mosheri morphotype C. To help reconcile the biochronological and geochemical data from New York Canyon, new conodont samples have been collected from the Nun Mine and Mt Hyatt members at the New York Canyon Road and Luning Draw sections. These samples contain: Mo. englandi, Mo. bidentata, and Mo. mosheri morphotypes B and C, all previously reported from New York Canyon, although this is the first record of Mo. mosheri morphotype C from the Nun Mine Member; Parvigondolella spp. B and C, from much lower in the Nun Mine Member than previously reported; and Pa. andrusovi, which has not previously been recorded from North America. Overall, this fauna represents the Mo. bidentata and Mo. mosheri zones of North America, equivalent to the Sevatian Mo. bidentata and Pa. andrusovi zones of Tethys. This would be consistent with a higher placement of the NRB at New York Canyon; however, if the NRB is to be recognized at the first occurrence of Mo. mosheri morphotype C, then the boundary must be lower than previously thought, within the Nun Mine Member. 

turnovers culminating in the so-called End-Triassic Extinction. We attribute onset of this interval of declining diversity to unusually high volcanic activity at the Norian/Rhaetian boundary (NRB) that may have initiated the stepwise extinctions of the Late Triassic [1]. We correlate the initiation of a rapid decline in 87Sr/86Sr and 187Os/188Os seawater values [2, 3] to a negative organic carbon isotope shift, which we attribute to volcanogenic CO2 outgassing to the ocean-atmosphere system by the Angayucham large igneous province (LIP). By studying the geochemical and isotope composition of bulk rocks from different sections located at different latitudes, sides of the Pangea continent and Hemispheres, we documented an accelerated chemical weathering due to global warming by elevated CO2, which enhanced nutrient discharge to the oceans and thus greatly increased biological productivity; higher export production and oxidation of organic matter led to oceanic dysoxia to anoxia at the NRB. Biotic consequences of these climatic and environmental changes include severe extinctions of several fossil groups, such as ammonoids, bivalves and radiolarians, as has been documented worldwide [1]. 

The Late Triassic was a time of major evolutionary transition for marine vertebrates, with the emergence of important new clades and the expansion of durophagy. The diversity record of shallow marine vertebrates has been limited by poor preservation, and palaeogeographic ranges of common marine vertebrates is poorly constrained. Isolated ichthyoliths are an important resource for documenting taxonomic and ecological diversity in shallow marine environments and have a relatively high preservation potential. Here, we report the first Upper Triassic elasmobranchs, neopterygians and chondrosteans from Nevada, and contribute 14 new generic occurrences. The vertebrates represented in this survey include teeth of specialised durophages and piscivores, and a tentative reconstruction of the shallow marine ecosystem trophic niches based on dietary interpretations and known shelly macrofossils from this locality. The ichthyolith assemblage exhibited greater similarity to low-latitude Europe than high-latitude Canada localities, and the results of this study suggest that several taxa previously considered to be endemic to Europe may be cosmopolitan. The present study highlights the need for additional research in early Mesozoic ichthyoliths in order to establish diversity patterns, paleobiogeographic ranges, and timing of adaptive radiations among key groups of marine vertebrates in the Triassic Period in suboptimal preservation conditions. 

Recent studies have found that for students entering college, altruism is a desired aspect of a future career. Problematically, few students perceived geoscience careers as altruistic or even expressed an understanding of the potential career paths in geoscience. This dissonance in incoming student perceptions of geoscience may be linked to declining major enrollment. Classically, geoscientists have often cited job benefits such as high income, working outdoors, and travel as reasons to pursue a career in geoscience, but these may not be as appealing to the next generation of scientists. This research seeks to test if alternative forms of outreach and recruitment that highlight geoscientists’ roles in renewable energy, remediation and environmental fields, and studying climate change alter students’ perceptions of geoscientists. To accomplish this, a co-operative game was developed, originally based on SERC activity 49774, a carbon cycle dice game by Callan Bentley. The activity was first modified by Ryan Hollister for the 2018 Earth Educators’ Rendezvous, where card sheets for reservoirs were introduced and edited to have students more explicitly calculate relative reservoir sizes, fluxes between reservoirs, and the duration carbon may spend in each reservoir. The game was further altered at North Dakota State University to make carbon reservoir cards more specific to the North Dakota-Minnesota region. The most recent iteration adds co-operative gameplay where students actively intervene in the carbon cycle through roles, including geoscientist, that can actively impact the climate. Our goal is to demonstrate the influence geoscience careers can have on modern challenges, such as climate change, in an engaging format. This most recent version of the game will be used as an alternative outreach tool. This research is currently underway, and data will be collected at middle school, high school, early college, and community events through 2022.