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Ghost-dune hollows on the eastern Snake River Plain (ESRP), Idaho, USA, are topographically inverted, crescent-shaped depressions that record the partial encasement of sand dunes by ca. 61 ka basalt lava flows. Deflation of these “ghost” sand dunes produced approximately two dozen, 5–10-m-deep ghost-dune hollows now incompletely filled with pedogenically altered eolian and colluvial sediment. Optically stimulated luminescence (OSL) and 40Ar/39Ar ages constrain a ghost-dune hollow model that illuminates the late Pleistocene to Holocene environmental and climate history of the ESRP. Detrital zircon analyses indicate sand-dune supply routes changed following the burial of Pleistocene Henrys Fork (tributary of the Snake River) alluvium by ca. 70 ka basalt flows. Removal of Henrys Fork alluvium from the eolian supply system made Lake Terreton sediment the primary source for later ESRP sand dunes. Such sediment supply changes highlight the potential impacts of effusive volcanism on sand-dune histories and landscapes. Our results support stratigraphic and sedimentary modeling of comparable ghost-dune 舠pit舡 deposits older than ca. 2 Ga on Mars that may have served as refugia for early life on that planet. Analogous ancient ghost-dune hollow deposits on Earth may also have served as early life refugia.

Proteins are critical in catalyzing chemical reactions, forming key cellular structures, and in regulating cellular processes. Investigation of marine microbial proteins by metaproteomics methods enables the discovery of numerous aspects of microbial biogeochemistry processes. However, these datasets present big-data challenges as they often involve many samples collected across broad geospatial and temporal scales, resulting in thousands of protein identifications, abundances, and corresponding annotation information. The Ocean Protein Portal (OPP) was created to enable data sharing and discovery among multiple scientific domains and serve both research and education functions. The portal focuses on three use case questions: “Where is my protein of interest?”, “Who makes it?”, and “How much is there?”, and provides profile and section visualizations, real-time taxonomic analysis, and links to metadata, sequence analysis, and other external resources to enabling connections to be made between biogeochemical and proteomics datasets.

We present METATRYP version 2 software that identifies shared peptides across the predicted proteomes of organisms within environmental metaproteomics studies to enable accurate taxonomic attribution of peptides during protein inference. Improvements include ingestion of complex sequence assembly data categories (metagenomic and metatranscriptomic assemblies, single cell amplified genomes, and metagenome assembled genomes), prediction of the least common ancestor (LCA) for a peptide shared across multiple organisms, increased performance through updates to the backend architecture, and development of a web portal (https://metatryp.whoi.edu). Major expansion of the marine METATRYP database with predicted proteomes from environmental sequencing confirms a low occurrence of shared tryptic peptides among disparate marine microorganisms, implying tractability for targeted metaproteomics. METATRYP was designed to facilitate ocean metaproteomics and has been integrated into the Ocean Protein Portal (https://oceanproteinportal.org); however, it can be readily applied to other domains. We describe the rapid deployment of a coronavirus-specific web portal (https://metatryp-coronavirus.whoi.edu/) to aid in use of proteomics on coronavirus research during the ongoing pandemic. A coronavirus-focused METATRYP database identified potential SARS-CoV-2 peptide biomarkers and indicated very few shared tryptic peptides between SARS-CoV-2 and other disparate taxa analyzed, sharing

We present METATRYP version-2 software that identifies shared peptides across organisms within environmental metaproteomics studies to enable accurate taxonomic attribution of peptides during protein inference. Improvements include: ingestion of complex sequence assembly data categories (metagenomic and metatranscriptomic assemblies, single cell amplified genomes, and metagenome assembled genomes), prediction of the Least Common Ancestor (LCA) for a peptide shared across multiple organisms, increased performance through updates to the backend architecture, and development of a web portal (https://metatryp.whoi.edu). Major expansion of the marine database confirms low occurrence of shared tryptic peptides among disparate marine microorganisms, implying tractability for targeted metaproteomics. METATRYP was designed for ocean metaproteomics and has been integrated into the Ocean Protein Portal (https://oceanproteinportal.org); however, it can be readily applied to other domains. We describe the rapid deployment of a coronavirus-specific web portal (https://metatryp-coronavirus.whoi.edu/) to aid in use of proteomics on coronavirus research during the ongoing pandemic. A Coronavirus-focused METATRYP database identified potential SARS-CoV-2 peptide biomarkers and indicated very few shared tryptic peptides between SARS-CoV-2 and other disparate taxa, sharing 0.1% peptides or less (1 peptide) with the Influenza A & B pan-proteomes, establishing that taxonomic specificity is achievable using tryptic peptide-based proteomic diagnostic approaches.Statement of significanceWhen assigning taxonomic attribution in bottom-up metaproteomics, the potential for shared tryptic peptides among organisms in mixed communities should be considered. The software program METATRYP v 2 and associated interactive web portals enables users to identify the frequency of shared tryptic peptides among taxonomic groups and evaluate the occurrence of specific tryptic peptides within complex communities. METATRYP facilitates phyloproteomic studies of taxonomic groups and supports the identification and evaluation of potential metaproteomic biomarkers.

Ocean metaproteomics is an emerging field enabling discoveries about marine microbial communities and their impact on global biogeochemical processes. Recent ocean metaproteomic studies have provided insight into microbial nutrient transport, colimitation of carbon fixation, the metabolism of microbial biofilms, and dynamics of carbon flux in marine ecosystems. Future methodological developments could provide new capabilities such as characterizing long-term ecosystem changes, biogeochemical reaction rates, and in situ stoichiometries. Yet challenges remain for ocean metaproteomics due to the great biological diversity that produces highly complex mass spectra, as well as the difficulty in obtaining and working with environmental samples. This review summarizes the progress and challenges facing ocean metaproteomic scientists and proposes best practices for data sharing of ocean metaproteomic data sets, including the data types and metadata needed to enable intercomparisons of protein distributions and annotations that could foster global ocean metaproteomic capabilities.

The St. Anthony Dune Field (SADF) is a ~300 km2 expanse of active to stabilized transverse, barchan, barchanoid, and parabolic sand dunes located in a semi-arid climate in southeastern Idaho. The northeastern portion of the SADF, ~16 km2, was investigated to examine meteorological influences on dune mobility. Understanding meteorological predictors of sand-dune migration for the SADF informs landscape evolution and impacts assessment of eolian activity on sensitive agricultural lands in the western United States, with implications for semi-arid environments globally. Archival aerial photos from 1954 to 2011 were used to calculate dune migration rates which were subsequently compared to regional meteorological data, including temperature, precipitation and wind speed. Observational analyses based on aerial photo imagery and meteorological data indicate that dune migration is influenced by weather for up to 5–10 years and therefore decadal weather patterns should be taken into account when using dune migration rates as proxies from climate fluctuation. Statistical examination of meteorological variables in this study indicates that 24% of the variation of sand dune migration rates is attributed to temperature, precipitation and wind speed, which is increased to 45% when incorporating lag time.

The Kulshan caldera formed at ∼1.15 Ma on the present-day site of Mt. Baker, Washington State, northwest USA and erupted a compositionally zoned (dacite-rhyolite) magma and a correlative eruptive, the Lake Tapps tephra. This tephra has previously been described, but only from the Puget Lowland of NW Washington. Here an occurrence of a Kulshan caldera correlative tephra is described from the Quaternary Palouse loess at the Washtucna site (WA-3). Site WA-3 is located in east-central Washington, ∼340 km southeast of the Kulshan caldera and ∼300 km east-southeast of the Lake Tapps occurrence in the Puget Lowland. Major- and trace element chemistry and location of the deposit at Washtucna within reversed polarity sediments indicates that it is not correlative with the Mesa Falls, Rockland, Bishop Ash, Lava Creek B or Huckleberry Ridge tephras. Instead the Washtucna deposit is related to the Lake Tapps tephra by fractional crystallisation, but is chemically distinct, a consequence of its eruption from a compositionally zoned magma chamber. The correlation of the Washtucna occurrence to the Kulshan caldera-forming eruption indicates that it had an eruptive volume exceeding 100 km3, and that its tephra could provide a valuable early-Pleistocene chronostratigraphic marker in the Pacific Northwest.

The middle Eocene White Lake and Skaha formations in the White Lake Basin, British Columbia record the sedimentary and volcanic infilling of a supradetachment basin that developed during the latter stages of Shuswap metamorphic core complex exhumation. The 1.1-km-thick White Lake Formation is characterized by volcanogenic sediment gravity flow, fluvial, and sheetflood facies interbedded with volcanic deposits. Facies relations suggest White Lake strata accumulated on coalesced, west-sloping alluvial fans that drained an active volcanic center. The overlying 0.3-km-thick Skaha Formation records increased tectonism and mass-wasting. Pervasively shattered Skaha avalanche, slide, and sheetflood deposits accumulated on alluvial fans, shed from hanging-wall and footwall sources exposed along the Okanagan Valley fault. Clast compositions of the White Lake and Skaha formations record alluvial and tectonic stripping that locally eliminated hanging-wall blocks. Mylonite clasts in upper Skaha beds imply significant Okanagan Valley fault footwall uplift during the middle Eocene and syntectonic erosion of the Shuswap metamorphic core complex. The syntectonic sedimentary record preserved within the White Lake Basin elucidates the relations and timing between core complex exhumation and extensional tectonism in this region. The White Lake and Skaha formations are the apparent age equivalent of the Klondike Mountain Formation of northern Washington (USA.). White Lake Basin strata, however, are more complexly interstratified, post-depositionally disrupted, and contain a more complete record of core complex unroofing. Variations in the spatial distributions and textural and compositional character of middle Eocene strata in this area underscore the need to exercise care when developing regional-scale sedimentary–tectonic–volcanic models.

A facies-based approach was used to delineate both geochemical and physical aquifer property heterogeneity. Specifically, the parameters considered were the sorption coefficient (Kd) for a model organic contaminant and hydraulic conductivity (K) inferred from the particle size distribution. Subfacies-sized samples were analyzed for both tetrachloroethene Kd and K in a vertical core of the Borden aquifer. Both parameters were correlated with the six sedimentary facies identified within the vertical core. As a consequence of their relations to sedimentary facies, significant positive correlations between ln K and ln Kd which were different from the core-scale correlation and different from each other were identified for some facies. Fades-specific correlations generally resulted in improved statistics (i.e., higher correlation coefficients and reduced confidence intervals) compared to the core-scale correlation. The results suggest that a facies-based approach can be useful in characterizing the heterogeneity of the transport properties of sedimentary aquifers.

A regional climate model (RCM) developed for the Hanford Site, Washington illustrates a potentially useful method for assessing eolian responses to regional climate change. The RCM is based on long-term relations between fundamental climatic variables of precipitation, temperature, and wind speed. Modelled data are integrated into eolian-climatic scenarios through maps of eolian susceptibility, plots of sand dune mobility, and calculated trends of unvegetated dune sand volumes. Results demonstrate the sensitivity of eolian-climatic interactions to small changes in precipitation. Analyses suggest that continuation of the 1977–1987 trend toward a cooler (−0.16°C) and wetter (+1.8 cm yr −1 ) climate over the next 10–15 years will result in a decrease of ∼18% in the volume of unvegetated dune sand. Further temperature reductions totaling 0.7°C would promote precipitation increases of 30% leading to an additional reduction of 98% in the volume of unvegetated dune sand. Modelling scenarios for a possible global warming of +4°C indicate that annual precipitation at Hanford would be negligible and vegetation would be eliminated from dune surfaces. Sand dune mobility would increase by over 400%.

[1] We determined the descriptive statistical and spatial geostatistical properties of the perchloroethene ln Kd and the ln k of a 1.5 m thick by 10 m horizontal transect of the Borden aquifer near the location of the Stanford-Waterloo (SW) tracer experiment. The ln Kd distribution is not normal and is right skewed because of a few high values that occur localized in two regions of the transect. In contrast, the ln k data can be characterized by a normal distribution. A linear regression of ln Kd on ln k yields a statistically significant positive correlation, also shown at small lags in the cross correlogram. No significant vertical or horizontal trend in the ln Kd data was detected. The semivariogram ranges of ln k and ln Kd differ from one another in the vertical direction (0.33 ± 0.06 m and 0.20 ± 0.04 m, respectively) and are much less than the horizontal ranges (a few meters). Despite significant effort the horizontal range of ln Kd remains poorly characterized because of limitations of the sample locations. Many of the characteristics described above do not match those assumed in prior theoretical studies that examined the importance of various aquifer characteristics on SW tracer transport. We suggest that there is knowledge to be gained by revisiting the conclusions of these prior studies in light of the new information presented here.

A highly crevassed region near a grounded ice rise on the Ross Ice Shelf, Antarctica was investigated and found to contain poorly sorted sediments. Preliminary analysis of a 27 g sample of sediments was undertaken using megascopic, microscopic, and X-ray diffraction methods. Igneous and meta-morphic rock fragments, their constituent minerals, and micro-fossils were noted in the sample. Insufficient data have been collected at this time to denote a particular source area for the sediments.

The integration of atmospheric soundings from a fully instrumented aircraft with detailed sedimentary and geomorphic analyses of eolian features in the Ferris dune field of south-central Wyoming lends insight into the manner in which topography interacts with airflow to modify eolian activity. Topographically modified airflow results in zones of airflow deceleration, acceleration, and enhanced atmospheric turbulence, all of which influence the surface morphology and sedimentology. Extreme lateral confluence of prevailing airflow produces accelerated, unidirectional winds. These winds correlate with unusually continuous and elongate parabolic dunes that extend into a mountain gap (Windy Gap). Persistently heightened winds produced at the entrance to Windy Gap have resulted in a concentration of active sand dunes that lack slipfaces. Common development of a strongly amplified atmospheric wave analogous to a hydraulic jump in the gap contributes to the formation of a variety of eolian features that mantle the surface of Windy Gap and the Ferris dune field tail. Heightened, unidirectional winds in this zone promote grain-size segregation, the formation of elongated and aligned sand drifts, climbing and falling dunes, elongate scour streaks, and parabolic dunes that have low-angle (< 20/sup 0/) cross-stratification. Deflation of bedrock and loose sediment has been enhanced in the zonemore » of maximum turbulence beneath the hydraulic jump.« less