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Fossils represented as Cloudina? were reported in the Antarctic Taylor Formation by Yochelson and Stump in 1977. Their assessment presented thin sections of specimens derived from an oolitic limestone breccia. Notably, one thin section contained a single presumed trilobite fragment, leading the authors to attribute the materials to the early Cambrian. The remaining fossil materials were characterized as tubes of varying preservational quality, likely overprinted by recrystallization. The structure of tubular fossils, as viewed in thin section, appeared bilayerd, showing a thicker outer layer surrounding a thinner, darker, inner layer, enveloping the innermost lumen or cavity of the tube. While one specimen was reported to have two layers, it lacked other identifying features, such as the characteristic nested structure typical of Cloudina. The authors acknowledged the dissimilarity of their specimens to those reported from Namibia by G.J.B. Germs but noted similarities to Cloudina borrelloi from the San Juan Province, Argentina described by Yochelson and Herrera in 1974. This led the authors to cautiously identify their Antarctic specimens as Cloudina?, though subsequent reports expressed skepticism about placing the Argentinian materials within the Cloudina genus, suggesting a more plausible association with Salterella or Acuticloudina. Based on this single report, Ediacaran paleontologists have often, but tenuously, expanded the geographic distribution of Cloudina to include Antarctica. As the International Commission on Stratigraphy’s Ediacaran Subcommission has defined the use of Ediacaran tubicolus organisms, including all plausible designations of Cloudina, as the leading index fossil group for placement of the terminal Ediacaran stage, this long-overdue reexamination is both timely and important for gaining a clearer picture of the cosmopolitan nature of this genus. Our initial analysis shows that these tubicolus taxa are single-walled, non-nested, and smooth-walled, gently tapering, conical tubes. Herein, we aim to aim to reevaluate the taxonomy of these fossils using modern microanalysis and high-resolution photography to shed light on their potential phylogeny and evaluate their role in the broader context of late Ediacaran to early Cambrian tubular fossils. 

Abstract Coastal aquifers play an important role in marine ecosystems by providing high fluxes of nutrients and solutes via submarine groundwater discharge pathways. The physical and chemical characterization of these dynamic systems is foundational to understanding the extent and magnitude of hydrogeologic processes and their subsequent contributions to the marine environment. We describe a km‐scale experimental field site located in a glaciofluvial delta entering Kachemak Bay, Alaska. Our characterization applies geophysical (ERT and HVSR), hydrogeologic (grain size analyses, slug tests and tidal response analyses) and geochemical (major ions and stable water isotopes) methods to describe the complexity of coastal aquifers in proglacial environments currently experiencing rapid transformations. The hydrogeologic and geophysical techniques revealed thick (20–84 m) sediments dominated by sands and gravels and delineated zones of freshwater, brackish water and saltwater at both high and low tides within the subterranean estuary. Estimates of hydraulic conductivities via multiple approaches ranged from 2 to 250 m d⁻¹, with means across the four methods within the same order of magnitude. Tidal response analyses highlighted a coastal aquifer in strong connection with the sea as evidenced by clear spring‐ and neap‐tidal signals within a proximal piezometric hydrograph. Geochemical sampling revealed coastal groundwaters as substantially enriched in solutes compared to proximal river samples with limited variability across seasons. A clear connection between the Wosnesenski River and the adjacent aquifer was also observed, with concentrated recharge from the river corridor during the meltwater season. This combination of approaches provides the basis for a conceptual model for coastal aquifer systems within the Gulf of Alaska and an upscaled mean daily yield of freshwater and solutes from the delta subsurface. Our findings are critical for subsequent numerical simulations of groundwater flow, tidal pumping and chemical reactions and transport in these understudied environments. This approach may be applied for low‐cost, large‐scale hydrogeologic investigations in coastal areas and may be particularly useful for remote sites where access and mobility are challenging. 

Abstract High latitude mountain environments are experiencing disproportionately adverse effects from climate change. The Gulf of Alaska (GoA) region is an embodiment of this change, particularly concerning a shifting hydrologic balance. Even so, the magnitude and contribution of fresh submarine groundwater discharge (fresh SGD) remains virtually unexplored within the region, though it has gained increasing attention globally due to its chemical significance and influence on coastal ecosystems. Here we provide the first regional estimates of fresh SGD to the GoA using two established water balance approaches. This is an effective way to distinguish the contribution of terrestrially derived fresh SGD, rather than the more commonly quantified total SGD which includes discharge that is driven by marine forces such as sea‐level oscillations and density gradients. We compare the approaches and assess their capabilities in computing the magnitude of fresh SGD over a large regional scale. Mean annual fresh SGD flux ranges between 26.5 and 86.8 km³ yr⁻¹to the GoA, equivalent to 3.5%–11.4% of the total freshwater discharge. Contributions are highest in the Southeastern panhandle and lowest in the Cook Inlet basin, with the highest area normalized contribution occurring in the Prince William Sound. Fresh SGD exhibits high spatial and temporal variability throughout the region. Although freshwater discharge to the GoA is investigated considerably, the importance of fresh SGD has, thus far, been overlooked. 

Abstract A Large Ion Collider Experiment (ALICE) has been conceived and constructed as a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a wide range of physics results using all collision systems available at the LHC. In order to best exploit new physics opportunities opening up with the upgraded LHC and new detector technologies, the experiment has undergone a major upgrade during the LHC Long Shutdown 2 (2019–2022). This comprises the move to continuous readout, the complete overhaul of core detectors, as well as a new online event processing farm with a redesigned online-offline software framework. These improvements will allow to record Pb-Pb collisions at rates up to 50 kHz, while ensuring sensitivity for signals without a triggerable signature.