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The Walker Lane belt and Eastern California shear zone of California, USA, are active, plate boundary–related dextral systems with transtensional and transpressional deformation, respectively. They are separated by the sinistral Garlock fault, creating a complex system without an overall integrated formation and evolution model. We examine the deformation within the eastern segment of the Garlock fault zone over geologic timescales by determining the slip history of faults. We assess the progression of faulting and associated deformation along the WSW-striking Garlock fault zone and how it applies to the overall NNW-directed dextral system. Previous studies found that large synthetic fault strands take up 30% of the slip of the Garlock fault zone and have proposed multiple mechanisms to explore how to accommodate regional NNW-directed shear across the Garlock fault without cutting its trace. We analyze an unstudied section of faulting in one of the more complex areas of regional deformation via compiled and reinterpreted published geologic data for an analysis of total and incremental slip on the main faults of the eastern Garlock fault zone. We identify geologic offset features to interpret total slip, timing, and deformation evolution. We find that 30% of the total slip of the Garlock zone occurs on strands other than the Garlock fault sensu stricto, with the locus of main slip sidestepping during the evolution of accommodation of throughgoing, regional dextral shear. Our results support ideas of the creation and evolution of the regional dextral system via stress concentration on a sub-Garlock lithospheric anisotropy with a resulting lowering of the plastic yield stress. Our results also show an eastward increase in fault system complexity, which may imply an underappreciated seismic hazard of the eastern Garlock fault zone.

IEDA, the Interdisciplinary Earth Data Alliance, is a unique collaborative data infrastructure that provides and continuously evolves a comprehensive ecosystem of data, tools, and services that support researchers in the Geosciences to share and access sample data following the FAIR data principles and ensure open, reproducible, and transparent science practices.The ‘next generation’ of IEDA - IEDA2 - was funded by the US National Science Foundation in 2022 for 5 years to advance the existing data systems and services of EarthChem (geochemistry data repository, data synthesis, and data access portals), LEPR/TraceDs (synthesis of data from petrological experiments), and SESAR (System for Earth Sample Registration), modernizing system architecture to better support computational and data-driven research, improving usability, and growing a diverse and inclusive user audience through education and engagement.Our target is to enable a common understanding of existing information that is validated through expert data curation to enable transparent and reproducible (re)use and analysis of data, inform peer review, and guide future research directions. Such common understanding cannot develop unless the community can access and assess the same information.This collective vision of the data will improve the ability of the entire community to assess the context and significance of new data and models, allow reviewers to evaluate new models that are calibrated using the data, and facilitate new generations of research.

The StraboSpot data system provides field-based geologists the ability to digitally collect, archive, query, and share data. Recent efforts have expanded this data system with the vocabulary, standards, and workflow utilized by the sedimentary geology community. A standardized vocabulary that honors typical workflows for collecting sedimentologic and stratigraphic field and laboratory data was developed through a series of focused workshops and vetted/refined through subsequent workshops and field trips. This new vocabulary was designed to fit within the underlying structure of StraboSpot and resulted in the expansion of the existing data structure. Although the map-based approach of StraboSpot did not fully conform to the workflow for sedimentary geologists, new functions were developed for the sedimentary community to facilitate descriptions, interpretations, and the plotting of measured sections to document stratigraphic position and relationships between data types. Consequently, a new modality was added to StraboSpot—Strat Mode—which now accommodates sedimentary workflows that enable users to document stratigraphic positions and relationships and automates construction of measured stratigraphic sections. Strat Mode facilitates data collection and co-location of multiple data types (e.g., descriptive observations, images, samples, and measurements) in geographic and stratigraphic coordinates across multiple scales, thus preserving spatial and stratigraphic relationships in the data structure. Incorporating these digital technologies will lead to better research communication in sedimentology through a common vocabulary, shared standards, and open data archiving and sharing.

Background: The etiology of lung cancer among never-smokers is unclear despite 15% of cases in men and 53% in women worldwide are not smoking-related. Metabolomics provides a snapshot of dynamic biochemical activities, including those found to be driving tumor formation and progression. This study used untargeted metabolomics with network analysis to agnostically identify network modules and independent metabolites in pre-diagnostic blood samples among never-smokers to further understand the pathogenesis of lung cancer. Methods: Within the prospective Shanghai Women’s Health Study, we conducted a nested case-control study of 395 never-smoking incident lung cancer cases and 395 never-smoking controls matched on age. We performed liquid chromatography high-resolution mass spectrometry to quantify 20,348 unique metabolic features in plasma. Because metabolic features are expected to be highly correlated and more likely to be involved in biological processes as a network of intertwined features than individually, we agnostically constructed 28 network modules using a weighted correlation network analysis approach. The associations between metabolite network modules and individual metabolites with lung cancer were assessed using conditional logistic regression models, adjusting for age, body mass index, and exposure to environmental tobacco smoke. We accounted for multiple testing using a false discovery rate (FDR) < 0.20. Results: We identified a network module of 122 metabolic features enriched in lysophosphatidylethanolamines that was associated with all lung cancer combined (p = 0.001, FDR = 0.028) and lung adenocarcinoma (p = 0.002, FDR = 0.056) and another network module of 440 metabolic features that was associated with lung adenocarcinoma (p = 0.014, FDR = 0.196). Metabolic features were enriched in pathways associated with cell growth and proliferation, including oxidative stress, bile acid biosynthesis, and metabolism of nucleic acids, carbohydrates, and amino acids, including 1-carbon compounds. Conclusions: Our prospective study suggests that untargeted plasma metabolomics in pre-diagnostic samples could provide new insights into the etiology of lung cancer in never-smokers. Replication and further characterization of these associations are warranted. Citation Format: Mohammad L. Rahman, Xiao-Ou Shu, Douglas Walker, Dean P. Jones, Wei Hu, Bu-tian Ji, Batel Blechter, Jason YY Wong, Qiuyin Cai, Gong Yang, Tu-Tang Gao, Wei Zheng, Nathaniel Rothman, Qing Lan. A nested case-control study of untargeted plasma metabolomics and lung cancer risk among never-smoking women in the prospective Shanghai Women’s Health Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6056.

Stable isotopes of mammoths and mastodons have the potential to illuminate ecological changes in late Pleistocene landscapes and megafaunal populations as these species approached extinction. The ecological factors at play in this extinction remain unresolved, but isotopes of bone collagen (δ13C, δ15N) and tooth enamel (δ13C, δ18O, 87Sr/86Sr) from midwestern North America are leveraged to examine ecological and behavioral changes that occurred during the last interglacial-glacial cycle. Both species had significant C3 contributions to their diets and experienced increasing levels of niche overlap as they approached extinction. A subset of mastodons after the last glacial maximum exhibit low δ15N values that may represent expansion into a novel ecological niche, perhaps densely occupied by other herbivores. Stable isotopes from serial and microsampled enamel show increasing seasonality and decreasing temperatures as mammoths transitioned from Marine Isotope Stage (MIS) 5e to glacial conditions (MIS 4, MIS 3, MIS 2). Isotopic variability in enamel suggests mobility patterns and life histories have potentially large impacts on the interpretation of their stable isotope ecology. This study further refines the ecology of midwestern mammoths and mastodons demonstrating increasing seasonality and niche overlap as they responded to landscape changes in the final millennia before extinction.

Exposed Pliocene–Pleistocene terrestrial strata provide an archive of the spatial and temporal development of a basin astride the sinistral Garlock fault in California. In the southern Slate Range and Pilot Knob Valley, an ∼2000-m-thick package of Late Cenozoic strata has been uplifted and tilted to the northeast. We name this succession the formation of Pilot Knob Valley and provide new chronologic, stratigraphic, and provenance data for these rocks. The unit is divided into five members that record different source areas and depositional patterns: (1) the lowest exposed strata are conglomeratic rocks derived from Miocene Eagle Crags volcanic field to the south and east across the Garlock fault; (2) the second member consists mostly of fine-grained rocks with coarser material derived from both southern and northern sources; and (3) the upper three members are primarily coarse-grained conglomerates and sandstones derived from the adjacent Slate Range to the north. Tephrochronologic data from four ash samples bracket deposition of the second member to 3.6–3.3 Ma and the fourth member to between 1.1 and 0.6 Ma. A fifth tephrochronologic sample from rocks south of the Garlock fault near Christmas Canyon brackets deposition of a possible equivalent to the second member of the formation of Pilot Knob Valley at ca. 3.1 Ma. Although the age of the base of the lowest member is not directly dated, regional stratigraphic and tectonic associations suggest that the basin started forming ca. 4–5 Ma. By ca. 3.6 Ma, the northward progradation fanglomerate sourced in the Eagle Crags region waned, and subsequent deposition occurred in shallow lacustrine systems. At ca. 3.3 Ma, southward progradation of conglomerates derived from the Slate Range began. Circa 1.1 Ma, continued southward progradation of fanglomerate with Slate Range sources is characterized by a shift to coarser grain sizes, interpreted to reflect uplift of the Slate Range. Overall, basin architecture and the temporal evolution of different source regions were controlled by activity on three regionally important faults—the Garlock, the Marine Gate, and the Searles Valley faults. The timing and style of motions on these faults appear to be directly linked to patterns of basin development.

Adolescence is a developmental period that encompasses, but is not limited to, puberty and continues into early adulthood. During this period, maturation and refinement are observed across brain regions such as the prefrontal cortex (PFC), which is critical for cognitive function. Adolescence is also a time when excessive alcohol consumption in the form of binge drinking peaks, increasing the risk of long-term cognitive deficits and the risk of developing an alcohol use disorder later in life. Animal models have revealed that adolescent ethanol (EtOH) exposure results in protracted disruption of neuronal function and performance on PFC-dependent tasks that require higher-order decision-making. However, the role of astrocytes in EtOH-induced disruption of prefrontal cortex-dependent function has yet to be elucidated. Astrocytes have complex morphologies with an extensive network of peripheral astrocyte processes (PAPs) that ensheathe pre- and postsynaptic terminals to form the ‘tripartite synapse.’ At the tripartite synapse, astrocytes play several critical roles, including synaptic maintenance, dendritic spine maturation, and neurotransmitter clearance through proximity-dependent interactions. Here, we investigate the effects of adolescent binge EtOH exposure on astrocyte morphology, PAP-synaptic proximity, synaptic stabilization proteins, and dendritic spine morphology in subregions of the PFC that are important in the emergence of higher cognitive function. We found that adolescent binge EtOH exposure resulted in subregion specific changes in astrocyte morphology and astrocyte-neuronal interactions. While this did not correspond to a loss of astrocytes, synapses, or dendritic spines, there was a corresponding region-specific and EtOH-dependent shift in dendritic spine phenotype. Lastly, we found that changes in astrocyte-neuronal interactions were not a consequence of changes in the expression of key synaptic structural proteins neurexin, neuroligin 1, or neuroligin 3. These data demonstrate that adolescent EtOH exposure results in enduring effects on neuron-glia interactions that persist into adulthood in a subregion-specific PFC manner, suggesting selective vulnerability. Further work is necessary to understand the functional and behavioral implications.

StraboSpot is a geologic data system that allows researchers to digitally collect, store, and share both field and laboratory data. StraboSpot is based on how geologists actually work to collect field data; although initially developed for the structural geology research community, the approach is easily extensible to other disciplines. The data system uses two main concepts to organize data: spots and tags. A spot is any observation that characterizes a specific area, a concept applicable at any spatial scale from regional to microscopic. Spots are related in a purely spatial manner, and consequently, one spot can enclose multiple other spots that themselves contain other spots. In contrast, tags provide conceptual grouping of spots, allowing linkages between spots that are independent of their spatial position. The StraboSpot data system uses a graph database, rather than a relational database approach, to increase flexibility and to track geologically complex relationships. StraboSpot operates on two different platform types: (1) a field-based application that runs on iOS and Android mobile devices, which can function in either Internet-connected or disconnected environments; and (2) a web application that runs only in Internet-connected settings. We are presently engaged in incorporating microstructural data into StraboSpot, as well as expanding to include additional field-based (sedimentology, petrology) and lab-based (experimental rock deformation) data. The StraboSpot database will be linked to other existing and future databases in order to provide integration with other digital efforts in the geological sciences and allow researchers to do types of science that were not possible without easy access to digital data.

Management of geochemical data needs to consider the sequence of phases in the lifecycle of these data from field to lab to publication to archive. It also needs to address the large variety of chemical properties measured; the wide range of materials that are analyzed; the different ways, in which these materials may be prepared for analysis; the diversity of analytical techniques and instrumentation used to obtain analytical results; and the many ways used to calibrate and correct raw data, normalize them to standard reference materials, and otherwise treat them to obtain meaningful and comparable results. In order to extract knowledge from the data, they are then integrated and compared with other measurements, formatted for visualization, statistical analysis, or model generation, and finally cleaned and organized for publication and deposition in a data repository. Each phase in the geochemical data lifecycle has its specific workflows and metadata that need to be recorded to fully document the provenance of the data so that others can reproduce the results. An increasing number of software tools are developed to support the different phases of the geochemical data lifecycle. These include electronic field notebooks, digital lab books, and Jupyter notebooks for data analysis, as well as data submission forms and templates. These tools are mostly disconnected and often require manual transcription or copying and pasting of data and metadata from one tool to the other. In an ideal world, these tools would be connected so that field observations gathered in a digital field notebook, such as sample locations and sampling dates, can be seamlessly send to an IGSN Allocating Agent to obtain a unique sample identifier with a QR code with a single click. The sample metadata would be readily accessible for the lab data management system that allows the researchers to capture information about the sample preparation, and that connects to the instrumentation to capture instrument settings and the raw data. The data would then be seamlessly accessed by data reduction software, visualized, and further compared to data from global databases that can be directly accessed. Ultimately, a few clicks will allow the user to format the data for publication and archiving. Several data systems that support different stages in the lifecycle of samples and sample-based geochemical data have now come together to explore the development of standardized interfaces and APIs and consistent data and metadata schemas to link their systems into an efficient pipeline for geochemical data from the field to the archive. These systems include StraboSpot (www.strabospot.org; data system for digital collection, storage, and sharing of both field and lab data), SESAR (www.geosamples.org; sample registry and allocating agent for IGSN), EarthChem (www.earthchem.org; publishers and repository for geochemical data), Sparrow (sparrow-data.org; data system to organize analytical data and track project- and sample-level metadata), IsoBank (isobank.org; repository for stable isotope data), and MacroStrat (macrostrat.org; collaborative platform for geological data exploration and integration).

StraboSpot (StraboSpot.org) is a digital data system for collection, management and sharing of geologic data from the macro- to the microscale. Due to the pandemic, it was not possible to organize field-based workshops and fieldtrips in Summer 2020 for demonstrating and eliciting community feedback on the StraboSpot data system. Rather, we decided to run a series of week-long virtual workshops to familiarize practioners with the StraboSpot data system. Workshops were organized by discipline (sedimentology, structural geology, and petrology), each with approximately 100 participants, including U.S.-based and foreign scientists. The daily structure of the workshop was a 2-3 hour block with presentations from several StraboSpot team members, followed by an afternoon help desk. We reassigned participant support costs (originally intended for field-based meetings) to provide a small ($200-250) stipend to U.S.-based participants if they agreed to fully input a data set into StraboSpot and make it publicly available. This approach to increasing engagement – which was not part of original dissemination plan – was extremely successful. Workshop participants who signed up for the stipend were generally very engaged in the data system, provided important feedback on the design and vocabulary, and are highly likely to use StraboSpot in the future. Further, it helped to populate the database. People who received the stipend also presented their StraboSpot projects to the larger group on the last day of the workshop, often with an impressive data set. Because of Covid restrictions on fieldwork in summer 2021, we intend to continue providing stipends for young professionals (graduate students, post-doctoral fellows) to use the StraboSpot system for their thesis or project-based fieldwork. In addition to getting detailed feedback, we hope these testers will become a cohort of motivated users that will teach and encourage others to use the StraboSpot data system.

The StraboSpot database allows users to permanently store and query geologic field data directly from a mobile application or through a web application at strabospot.org. The first version of the mobile application, StraboSpot, has many of the features needed to collect data in the field, including offline basemaps, a developed vocabulary, and a built-in compass. However, it was intended for use on small smartphones, and users found the form-style user interface inefficient and cumbersome to use. The newly developed StraboSpot2 packages the same core functionality of the original Strabospot into an intuitive, simple design that greatly increases data collection efficiency. Because the target device in an iPad (of any size), we were able to take a map-based approach that fits multiple different types of field workflows and expands the ability for the user to view and explore datasets. New core features include: 1) Color-coding of points and polygons by customizable geological unit tags or conceptual tags; 2) Viewing all data collected at a spot in a “notebook view”; 3) Making sketches or annotate photographs; 4) Filtering spots, images, or tags by map extent; and 5) Facilitating the back up of datasets using integration with the iPadOS file system. StraboSpot2 is developed in React Native, a cross-platform development environment. This development environment will allow future versions to possibly support iPhone (iOS) and Android devices.

The StraboSpot digital data system is designed to allow researchers to digitally collect, store, and share both field and laboratory data. Originally designed for structural geology field data, StraboSpot has been extended to field-based petrology and sedimentology. Current efforts will integrate micrographs and data related to microscale and experimental rock deformation. The StraboSpot data system uses a graph database, rather than a relational database approach. This approach increases its flexibility and allows the system to track geologically complex relationships. StraboSpot currently operates on two different platform types: (1) a field-based application that functions with or without internet access; and (2) a web interface (Internet-connected settings only). The data system uses two main concepts - spots and tags - to organize data. A spot consists of a specific area at any spatial scale of observation. Spots are related in a purely spatial manner, and consequently, one spot can enclose multiple other spots that themselves contain spots. Spatial data can thus be tracked from regional to microscopic scale. Tags provide conceptual grouping of spots, allowing linkages between spots that are independent of their spatial position. A simple example of a tag is a geologic unit or formation. Multiple tags can be assigned to any spot, and tags can be assigned throughout a field study. The advantage of tags is their flexibility, in that they can be completely defined by individual scientists. Critically, tags are independent of the spatial scale of the observation. Tags may also be used to accommodate complex and complete descriptions. The strength of the StraboSpot platform is its flexibility, and that it can be linked to other existing and future databases in order to integrate with digital efforts across the geological sciences. The StraboSpot data system – in coordination with other digital data efforts – will allow researchers to conduct types of science that were previously not possible and allows geologists to join big data initiatives.

Stable isotopes of mammoths and mastodons have the potential to illuminate ecological changes in late Pleistocene landscapes and megafaunal populations as these species approached extinction. The ecological factors at play in this extinction remain unresolved, but isotopes of bone collagen (δ13C, δ15N) and tooth enamel (δ13C, δ18O, 87Sr/86Sr) from the Midwest, USA are leveraged to examine ecological and behavioral changes that occurred during the last interglacial-glacial cycle. Both species had significant C3 contributions to their diets and experienced increasing levels of niche overlap as they approached extinction. A subset of mastodons after the last glacial maximum (LGM) exhibit low δ15N values that may represent expansion into a novel ecological niche, perhaps densely occupied by other herbivores. Stable isotopes from serial and micro-sampled enamel show increasing seasonality and decreasing temperatures as mammoths transitioned from Marine Isotope Stage (MIS) 5e to glacial conditions (MIS 4, MIS 3, MIS 2). Isotopic variability in enamel suggests mobility patterns and life histories have potentially large impacts on the interpretation of their stable isotope ecology. This study further refines the ecology of midwestern mammoths and mastodons demonstrating increasing seasonality and niche overlap as they responded to landscape changes in the final millennia before extinction.