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Objective In recent years, with the expansion of the concept of sustainable development in the life cycle of construction projects and the dynamic and eventful nature of these projects, the issue of sustainable risk management has garnered increasing attention from researchers. However, the lack of systematic reviews and bibliometric analyses of published research in this field has obscured the future perspectives and evolution of this area of study. This study aims to evaluate and synthesize the existing body of literature to identify potential research gaps and delineate the boundaries of knowledge in the risk management of sustainable construction projects (SCPs). Methods This study is descriptive-analytical and is classified as a systematic review in terms of implementation method. The PRISMA guidelines were adopted for the systematic review of the literature, including descriptive and content analysis. In this process, 1,630 articles published in the Scopus and Web of Science databases from 2015 to 2023 were retrieved and screened, resulting in 113 eligible articles for analysis. To complete the systematic literature review, a bibliometric analysis encompassing co-authorship and keyword co-occurrence analysis was conducted using VOSviewer software for a more comprehensive evaluation of the field of risk management in sustainable construction projects (SCPs). Results Regarding the descriptive analysis of the retrieved papers based on the year of publication and their frequency in various journals, it was found that research on risk management in sustainable construction projects (SCPs) has increased in recent years. The content analysis of the articles, based on research themes, indicated that the articles were classified into five main themes: general risks of sustainability, sustainable procurement, supply chain, technology adoption, and human resources. A deeper exploration of the papers revealed that SCPs' risks were primarily categorized into eight dimensions: financial and economic; social; executive, managerial, and organizational; knowledge and skills; governmental and legal; stakeholders/employers; environmental; and technology, equipment, and resources. According to the research methods, experimental and applied research contributions in SCPs' risk management were less prevalent compared to descriptive and review research. This highlights opportunities for conducting applied research that addresses various problems and assumptions. In terms of strategy, a significant number of papers employed the survey method, with some based on case studies. Given that the accuracy and generalizability of survey research results are typically higher than those of case studies, there is a noticeable preference for the survey strategy among researchers. Additionally, researchers often used statistical analysis methods to assess SCPs' risks. According to the bibliometric analysis and the keyword co-occurrence results in the field of SCPs' risk management, it is anticipated that future researchers will focus more on concepts, approaches, and fields such as the circular economy, recycling, risk assessment, factor analysis, leadership in energy and environment, developing countries, and questionnaire surveys. Conclusion According to the findings, future articles are expected to focus on completing the puzzle of sustainability risk management systems in sustainable construction projects (SCPs), specifically addressing identification, evaluation, control, and response to risk. This focus should be particularly prominent in developing countries and should be approached through experimental and applied studies utilizing mixed methods and hybrid approaches under uncertainty. Various studies have examined barriers and risks in construction projects from different sustainability perspectives, such as economic, environmental, and social. However, the economic dimension has received more attention from researchers than others, which does not provide a comprehensive assessment of the risks associated with sustainable projects. Such comprehensive studies are crucial for the efficient allocation of resources. The primary contribution of this research to the bibliometric analysis of SCPs' risk management lies in its unique approach to determining the direction of future research. [ABSTRACT FROM AUTHOR]

Small meteoroids that enter Earth's atmosphere often go unnoticed because their detection and characterization rely on human observations, introducing observational biases in space and time. Acoustic shockwaves from meteoroid ablation convert to infrasound and seismic energy, enabling fireball detection using seismoacoustic methods. We analyzed an unreported fireball in 2022 near the Azores, recorded by 26 seismometers and two infrasound arrays. Through polarization analyses, array methods, and 3‐D ray‐tracing, we determined that the terminal blast occurred at 40 km altitude, ∼60 km NE of São Miguel Island. This location matches an unidentified flash captured by a lightning detector aboard the GOES‐16 satellite. The estimated kinetic energy is ∼10−3 kT TNT equivalent, suggesting a 10−1 m object diameter, thousands of which enter the atmosphere annually. Our results demonstrate how geophysical methods, in tandem with satellite data, can significantly improve the observational completeness of meteoroids, advancing our understanding of their sources and entry processes. Plain Language Summary: Every year, hundreds to thousands of small near‐Earth objects, known as meteoroids, enter Earth's atmosphere. Their hypersonic entry speed and break‐up can generate flashes known as fireballs and associated shockwaves that can reach the ground. However, it is only the largest objects breaking up above populated areas that we typically see or hear, or that are captured by dedicated camera systems. Many of the smaller meteoroids go unnoticed. This observational bias limits our understanding of these objects and how they enter Earth's atmosphere. Here, we report on a fireball that broke up over the Northern Atlantic Ocean in June 2022 and was recorded on a network of seismometers that record sensitive ground motion and infrasound sensors that "hear" low‐frequency sound waves. Our analyses of these data show a small (40 cm diameter) meteoroid exploded at around 40 km altitude and 60 km northeast of São Miguel Island. Crucially, a flash recorded by a lightning mapper aboard a weather satellite provides us with the exact time of the explosion. To the best of our knowledge, this event is one of few documented cases of a fireball detected solely by geophysical means without relying on initial reports from human observers or photographic/video evidence. Key Points: We use seismic and infrasound data to characterize a previously unreported fireball over the North Atlantic Ocean in June 2022The fireball was detected by the Geostationary Lightning Mapper onboard the GOES‐16 satellite, giving a precise constraint on blast timeSeismoacoustic data, in tandem with satellite observations, can help to improve our observational completeness of near‐Earth objects [ABSTRACT FROM AUTHOR]

In industry, there are some resources for working with legacy code [[8]] ("legacy code" essentially translates to "other people's code"). Often the main issue with running other people's code is using the correct version of the programming language and the code dependencies. Doing this ensures it will always be possible to move the code back to a previous state, even when mistakes are introduced, leaving you free to modify the code without fear of losing the original version of the code you inherited. [Extracted from the article]

We present a new dataset for the task of toponym resolution in digitized historical newspapers in English. It consists of 343 annotated articles from newspapers based in four different locations in England (Manchester, Ashton-under-Lyne, Poole and Dorchester), published between 1780 and 1870. The articles have been manually annotated with mentions of places, which are linked—whenever possible—to their corresponding entry on Wikipedia. The dataset consists of 3,364 annotated toponyms, of which 2,784 have been provided with a link to Wikipedia. The dataset is published in the British Library shared research repository, and is especially of interest to researchers working on improving semantic access to historical newspaper content. [ABSTRACT FROM AUTHOR]

Distributions of slabs within Earth's mantle are increasingly used to reconstruct past subduction zones, based on first‐order assumptions that slabs sink vertically after slab break‐off, and thus delineate paleo‐trench locations. Non‐vertical slab motions, which occur prior to break‐off, represent a potentially significant source of error for slab‐based plate reconstructions, but are poorly understood. We constrain lateral migration of the Indian slab and overlying India‐Asia collision zone by comparing tomographically imaged mantle structure with plate‐kinematic constraints. Following coupling of the Indian and Australian plates at the onset of collision, ∼1,000 km lateral migration of the Indian slab was driven by vertical subduction of the Australian slab. The sinking behaviors of individual slabs do not evolve in isolation, but instead influence, or are influenced by, other slabs in the same plate network. Hence, lateral slab migrations may be determined by interpreting the sinking behavior of slabs collectively, and with respect to plate kinematics. Plain Language Summary: To understand the links between plate tectonics and mantle processes, researchers must determine how tectonic plates have moved with respect the evolving mantle through geological time. To overcome this problem, recent studies use the locations of subducted slabs in the deep mantle to reconstruct plate motions, based on the hypothesis that slabs sink vertically through the mantle, and therefore mark the surface locations of past subduction zones. Here, we test slab sinking hypotheses, and their use in plate reconstruction modeling, by investigating the sinking kinematics of the subducting Indian and Australian slabs during the India‐Asia collision. Our analysis indicates that since onset of collision at ∼45–40 Ma, the Indian slab migrated laterally, ∼1,000 km northwards through the mantle, driven by subduction of the neighboring Australian slab. We arrive at this new interpretation because we interpret Indian and Australian slab kinematics collectively, and with respect to India‐Australia plate motions. Our study shows that the sinking behavior of one slab can influence that of another slab in the same network. Slab‐based plate reconstructions should therefore interpret slabs of the same network collectively, and with respect to plate motions, in order to constrain non‐vertical slab motions and avoid potentially significant plate reconstruction errors. Key Points: Subduction of Australian oceanic lithosphere drove northward motion of coupled India‐Australia plate since onset of collision at 45–40 MaBuoyant Indian continent stalled subduction of Indian slab whilst Australian slab subduction drove motion of coupled India‐Australia plateApproximately 1,000 km north lateral migration of Indian slab occurred to maintain compatibility with plate kinematics of coupled India‐Australia plate [ABSTRACT FROM AUTHOR]

We analyze mantle structure under South America in the DETOX‐P1 seismic tomography model, a global‐scale, multifrequency inversion of teleseismic P waves. DETOX‐P1 inverts the most extensive data set of broadband, waveform‐based traveltime measurements to date, complemented by analyst‐picked traveltimes from the ISC‐EHB catalog. The mantle under South America is sampled by ∼665,000 cross‐correlation traveltimes measured on 529 South American broadband stations and on 5,389 stations elsewhere. By their locations, depths, and geometries, we distinguish four high‐velocity provinces under South America, interpreted as subducted lithosphere ("slabs"). The deepest (∼1,800–1,200 km depth) and shallowest (<600 km) slab provinces are observed beneath the Andean Cordillera near the continent's northwest coast. At intermediate depths (1,200–900 km, 900–600 km), two slab provinces are observed farther east, under Brazil, Bolivia and Venezuela, with links to the Caribbean. We interpret the slabs relative to South America's paleo‐position over time, exploring the hypothesis that slabs sank essentially vertically after widening by viscous deformation in the mantle transition zone. The shallowest slab province carries the geometric imprint of the continental margin and represents ocean‐beneath‐continent subduction during Cenozoic times. The deepest, farthest west slab complex formed under intra‐oceanic trenches during late Jurassic and Cretaceous times, far west of South America's paleo‐position adjoined to Africa. The two intermediate slab complexes record the Cretaceous transition from westward intra‐oceanic subduction to eastward subduction beneath South America. This geophysical inference matches geologic records of the transition from Jura‐Cretaceous, extensional "intra‐arc" basins to basin inversion and onset of the modern Andean arc ∼85 Ma. Plain Language Summary: Eastward subduction of the Pacific basin lithosphere beneath South America has generated arc magmatism and produced the modern Andes. However, extrapolation of the modern east‐dipping subduction scenario to before the Late Cretaceous does not readily explain the contrasting history of the ancestral Andes. Subducted former seafloor continues to exist in the mantle and remains visible to seismic tomography because P waves travel faster in it than in ambient mantle. We analyze such seismically fast domains, that is, "slabs" of interpreted paleo‐seafloor, at depths of ∼300–1,800 km in our global tomography model DETOX‐P1. Combining these observations with quantitative plate reconstructions and geological observations, we attempt to reconstruct the subduction history under South America. The slab that dips eastward down beneath the present‐day Andes is relatively continuous to ∼900 km depth. Deeper down, slab geometries completely change. Voluminous slabs are unexpectedly imaged thousands of kilometers west of South America's reconstructed paleo‐margin. We argue that in the simplest explanation all slabs sank essentially in place, and a trans‐American, tectonic reconfiguration occurred the time equivalent to 900 km slab depth (∼80–90 Ma). Prior to this time, the "Andean" trench sat offshore (and the margin extended) but the subduction direction must have been oceanward, rather than eastward. Key Points: Global‐scale teleseismic P wave tomography model DETOX‐P1 is analyzed under South AmericaThe shallowest and the deepest slabs are found under (north)west South America, while intermediate‐depth slabs are found farther eastIf slabs sank roughly vertically, they initially formed under intra‐oceanic trenches, up until Late Cretaceous times [ABSTRACT FROM AUTHOR]

Although the Ordnance Survey has itself been the subject of historical research, scholars have not systematically used its maps as primary sources of information. This is partly for disciplinary reasons and partly for the technical reason that high-quality maps have not until recently been available digitally, geo-referenced, and in color. A final, and crucial, addition has been the creation of item-level metadata which allows map collections to become corpora which can for the first time be interrogated en masse as source material. By applying new Computer Vision methods leveraging machine learning, we outline a research pipeline for working with thousands (rather than a handful) of maps at once, which enables new forms of historical inquiry based on spatial analysis. Our 'patchwork method' draws on the longstanding desire to adopt an overall or 'complete' view of a territory, and in so doing highlights certain parallels between the situation faced by today's users of digitized maps, and a similar inflexion point faced by their predecessors in the nineteenth century, as the project to map the nation approached a form of completion. [ABSTRACT FROM AUTHOR]

We present four types of neural language models trained on a large historical dataset of books in English, published between 1760 and 1900, and comprised of ?5.1 billion tokens. The language model architectures include word type embeddings (word2vec and fastText) and contextualized models (BERT and Flair). For each architecture, we trained a model instance using the whole dataset. Additionally, we trained separate instances on text published before 1850 for the type embeddings, and four instances considering different time slices for BERT. Our models have already been used in various downstream tasks where they consistently improved performance. In this paper, we describe how the models have been created and outline their reuse potential. [ABSTRACT FROM AUTHOR]

Plate reconstructions since the breakup of Pangaea are mostly based on the preserved spreading history of ocean basins, within absolute reference frames that are constrained by a combination of age‐progressive hotspot tracks and paleomagnetic data. The evolution of destructive plate margins is difficult to constrain from surface observations as much of the evidence has been subducted. Seismic tomography can directly constrain paleotrench locations by imaging subducted lithosphere in the mantle. This new evidence, combined with the geological surface record of subduction, suggests that several intraoceanic arcs existed between the Farallon Ocean and North America during late Mesozoic times—in contrast to existing quantitative models that typically show long‐lived subduction of the Farallon plate beneath the continental margin. We present a continuously closing plate model for the eastern Pacific basin from 170 Ma to present, constrained using "tomotectonic analysis"—the integration of surface and subsurface data. During the Middle to Late Jurassic, we show simultaneous eastward and westward subduction of oceanic plates under an archipelago composed of Cordilleran arc terranes. As North America drifts westward, it diachronously overrides the archipelago and its arcs, beginning in the latest Jurassic. During and post‐accretion, Cordilleran terranes are translated thousands of kilometers along the continental margin, as constrained by paleomagnetic evidence. Final accretions to North America occur during the Eocene, ending ~100 Myr of archipelago override. This model provides a detailed, quantitative tectonic history for the eastern Pacific domain, paving the way for tomotectonic analysis to be used in other paleo‐oceanic regions. Plain Language Summary: Tectonic plate reconstructions back to the Jurassic period are mostly based on data from preserved ocean crust. However, many oceanic plates have been lost into the Earth's interior by subduction, making their reconstruction a challenge. We combine seismic images of the deep mantle with geological data to locate the vanished plates in the Earth's mantle and restore them to their previous positions at the surface. The trenches where the plates subducted can be paired with extinct arc volcanoes in western North America. Jointly, these lines of evidence suggest that the eastern Pacific basin was broken up into several smaller plates—in contrast to the long‐held view that one or two large plates subducted eastward beneath the west coast of North America for the last 170 Myr. Instead, we model simultaneous eastward and westward subduction of plates under a vast archipelago of volcanic arcs that sat stationary in the northeastern proto‐Pacific. North America was pulled westward into this archipelago and gradually collided with its microcontinents, which today form the North American Cordillera. Our model provides a more detailed and complete tectonic history for the eastern Pacific and highlights how our method can be used to reconstruct vanished oceans. Key Points: We present a plate reconstruction model for western North America and the eastern Pacific for the past 170 MyrThe plate model uses "tomotectonic analysis"—a synthesis of mantle and geological evidenceDetailed terrane motions show the assembly of the North American Cordillera from an intraoceanic arc setting [ABSTRACT FROM AUTHOR]

In global-scale seismic tomography, teleseismic P and PP waves mainly constrain structures in the upper two thirds of the mantle, whereas core-diffracted waves (Pdiff) constrain the lower third. This study is the first to invert a very large data set of Pdiff waves, up to the highest possible frequencies. This results in tomographic resolution matching and exceeding that of global S -wave tomographies, which have long been the models of choice for interpreting lowermost mantle structure. We present three new global tomography models of 3-D isotropic P -wave velocity in the earth's mantle. Multifrequency cross-correlation traveltimes are measured on all phases in passbands from 30 s dominant period to the highest frequencies that produce satisfactory fits (≈3 s). Model DETOX-P1 fits ≈2.5 M traveltimes from teleseismic P waves. DETOX-P2 fits the same data, plus novel measurements of ≈1.4 M traveltimes of Pdiff waves. DETOX-P3 fits the same data as DETOX-P2, plus ≈ 1.2 M PP traveltimes. Synthetics up to 1 s dominant period are computed by full wave propagation in a spherically symmetric earth using the spectral-element method AxiSEM. Traveltimes are linked to 3-D velocity perturbations (d VP / VP) by finite-frequency Fréchet kernels, parametrized on an adaptive tetrahedral grid of ≈400 000 vertices spaced by ≈80 km in the best-sampled regions. To complete spatial coverage, the waveform cross-correlation measurements are augmented by ≈5.7 million analyst-picked, teleseismic P arrival times. P , Pdiff and PP traveltimes are jointly inverted for 3-D isotropic P -velocity anomalies in the mantle and for events corrections, by least squares solution of an explicit matrix–vector equation. Inclusion of Pdiff traveltimes (in DETOX-P2, -P3) improves the spatial sampling of the lowermost mantle 100- to 1000-fold compared to teleseismic P waves (DETOX-P1). Below ≈2400 km depth, seismically slow anomalies are clustered at southern and equatorial latitudes, in a dozen or more intensely slow patches of 600–1400 km diameter. These features had long been classed into two large low shear velocity provinces (LLVP), which now appears questionable. Instead, patches of intensely slow anomalies in the lowermost mantle seem to form a nearly continuous, globe-spanning chain beneath the southern hemisphere, according to our increased resolution of LLVP-internal subdivisions and newly imaged patches beneath South America. Our tomography also supports the existence of whole-mantle plumes beneath Iceland, Ascension, Afar, Kerguelen, Canary, Azores, Easter, Galapagos, Hawaii, French Polynesia and the Marquesas. Seismically fast structure in the lowermost mantle is imaged as narrowly elongated belts under Eastern Asia and the Americas, presumably reflecting the palaeo-trench geometries of subduction zones and arcs that assembled Eastern Asia and the American Cordilleras in Palaeozoic and early Mesozoic times. Mid-mantle structure is primarily constrained by teleseismic P waves, but Pdiff data have a stabilizing effect, for example, sharpening the geometries of subducted slabs under the Americas, Eurasia and the Northern Pacific in the upper 2000 km. PP traveltimes contribute complementary constraints in the upper and mid mantle, but they also introduce low-velocity artefacts beneath the oceans, through downward smearing of lithospheric structure. Our three new global P -wave models can be accessed and interactively visualized through the SubMachine web portal (http://submachine.earth.ox.ac.uk/). [ABSTRACT FROM AUTHOR]

We present a novel numerical method to simulate global seismic wave propagation in realistic aspherical 3-D earth models across the observable frequency band of global seismic data. Our method, named AxiSEM3D, is a hybrid of spectral element method (SEM) and pseudospectral method. It describes the azimuthal dimension of global wavefields with a substantially reduced number of degrees of freedom via a global Fourier series parametrization, of which the number of terms can be locally adapted to the inherent azimuthal complexity of the wavefields. AxiSEM3D allows for material heterogeneities, such as velocity, density, anisotropy and attenuation, as well as for finite undulations on radial discontinuities, both solid–solid and solid–fluid, and thereby a variety of aspherical Earth features such as ellipticity, surface topography, variable crustal thickness, undulating transition zone and core–mantle boundary topography. Undulating discontinuities are honoured by means of the 'particle relabelling transformation', so that the spectral element mesh can be kept spherical. The implementation of the particle relabelling transformation is verified by benchmark solutions against a discretized 3-D SEM, considering ellipticity, topography and bathymetry (with the ocean approximated as a hydrodynamic load) and a tomographic mantle model with an undulating transition zone. For the state-of-the-art global tomographic models with aspherical geometry but without a 3-D crust, efficiency comparisons suggest that AxiSEM3D can be two to three orders of magnitude faster than a discretized 3-D method for a seismic period at 5 s or below, with the speed-up increasing with frequency and decreasing with model complexity. We also verify AxiSEM3D for localized small-scale heterogeneities with strong perturbation strength. With reasonable computing resources, we have achieved a corner frequency of up to 1 Hz for 3-D mantle models. [ABSTRACT FROM AUTHOR]

Abstract: We present SubMachine, a collection of web‐based tools for the interactive visualization, analysis, and quantitative comparison of global‐scale data sets of the Earth's interior. SubMachine focuses on making regional and global‐scale seismic tomography models easily accessible to the wider solid Earth community, in order to facilitate collaborative exploration. We have written software tools to visualize and explore over 30 tomography models—individually, side‐by‐side, or through statistical and averaging tools. SubMachine also serves various nontomographic data sets that are pertinent to the interpretation of mantle structure and complement the tomographies. These include plate reconstruction models, normal mode observations, global crustal structure, shear wave splitting, as well as geoid, marine gravity, vertical gravity gradients, and global topography in adjustable degrees of spherical harmonic resolution. By providing repository infrastructure, SubMachine encourages and supports community contributions via submission of data sets or feedback on the implemented toolkits. [ABSTRACT FROM AUTHOR]

We present obspyDMT, a free, open-source software toolbox for the query, retrieval, processing and management of seismological data sets, including very large, heterogeneous and/or dynamically growing ones. ObspyDMT simplifies and speeds up user interaction with data centers, in more versatile ways than existing tools. The user is shielded from the complexities of interacting with different data centers and data exchange protocols and is provided with powerful diagnostic and plotting tools to check the retrieved data and metadata. While primarily a productivity tool for research seismologists and observatories, easy-to-use syntax and plotting functionality also make obspyDMT an effective teaching aid. Written in the Python programming language, it can be used as a stand-alone command-line tool (requiring no knowledge of Python) or can be integrated as a module with other Python codes. It facilitates data archiving, preprocessing, instrument correction and quality control - routine but nontrivial tasks that can consume much user time. We describe obspyDMT's functionality, design and technical implementation, accompanied by an overview of its use cases. As an example of a typical problem encountered in seismogram preprocessing, we show how to check for inconsistencies in response files of two example stations. We also demonstrate the fully automated request, remote computation and retrieval of synthetic seismograms from the Synthetics Engine (Syngine) web service of the Data Management Center (DMC) at the Incorporated Research Institutions for Seismology (IRIS). [ABSTRACT FROM AUTHOR]

The lower third of the mantle is sampled extensively by body waves that diffract around the earth's core (Pdiff and Sdiff phases), which could deliver highly resolved tomographic images of this poorly understood region. But core-diffracted waves-especially Pdiff waves- are not often used in tomography because they are difficult to model adequately. Our aim is to make core-diffracted body waves usable for global waveform tomography, across their entire frequency range. Here we present the data processing part of this effort. A method is demonstrated that routinely calculates finite-frequency traveltimes of Pdiff waves by crosscorrelating large quantities of waveform data with synthetic seismograms, in frequency passbands ranging from 30.0 to 2.7 s dominant period. Green's functions for 1857 earthquakes, typically comprising thousands of seismograms, are calculated by theoretically exact wave propagation through a spherically symmetric earth model, up to 1 Hz dominant period. Out of 418 226 candidates, 165 651 (39.6 per cent) source-receiver pairs yielded at least one successful passband measurement of a Pdiff traveltime anomaly, for a total of 479 559 traveltimes in the eight passbands considered. Measurements of teleseismic P waves yielded 448 178 usable source-receiver paths from 613 057 candidates (73.1 per cent success rate), for a total of 2 306 755 usable teleseismic dT in eight passbands. Observed and predicted characteristics of Pdiff traveltimes are discussed and compared to teleseismic P for this very large data set. Pdiff measurements are noise-limited due to severe wave attenuation with epicentral distance and frequency. Measurement success drops from 40-60 per cent at 80° distance, to 5-10 per cent at 140°. Frequency has a 2-3 times stronger influence on measurement success for Pdiff than for P. The fewest usable dT measurements are obtained in the microseismic noise band, whereas the fewest usable teleseismic P measurements occur at the highest frequencies. dT anomalies are larger for Pdiff than for P, and frequency dependence of dT due to 3-D heterogeneity (rather than just diffraction) is larger for Pdiff aswell. Projecting the Pdiff traveltime anomalies on their core-grazing segments, we retrieve well-known, large-scale structural heterogeneities of the lowermostmantle, such as the two Large Low Shear Velocity Provinces, an Ultra-Low Velocity Zone west of Hawaii, and subducted slab accumulations under East Asia and Central America. [ABSTRACT FROM AUTHOR]

We present two high-resolution body-wave tomography models of the whole mantle column, beneath the western Indian Ocean, centered on the volcanic hotspot of La Reunion, the presumed location of a deep mantle plume. The P-wave model shows a source in the lowermost mantle for the upwelling beneath La Réunion, rooted in the African LLSVP. The model is consistent with previous studies observing 'fat' plumes in the lower mantle but reveals more detail and considerable complexity in the transition zone and upper mantle beneath the Réunion hotspot. Rather than being near-vertical, the upwelling shows a tilt in the lower mantle (2000-1000 km depth) and splits into branches closer to the surface (upper 600 km).The new S-model consists of three datasets: teleseismic multifrequency waveform measurements from the ocean-bottom and island-based RHUM-RUM experiment around La Réunion (2011-2015, Barruol & Sigloch, 2013); cross-correlation measurements of teleseismic S-waves from S40RTS (Ritsema et al., 2011); and picked S-phases from the ISC/ISC-EHB catalog (Weston et al., 2018). Like the P-model, the S-model reveals a whole-mantle, low-velocity upwelling rooted in the African LLVP. The two models are highly correlated throughout the mantle but additional low-velocity features are imaged by the S-model in the upper mantle. [ABSTRACT FROM AUTHOR]

Benjamin Fernando, Kasra Hosseini and Maria Tsekhmistrenko describe how blind testing is helping to train martian seismologists. [ABSTRACT FROM AUTHOR]

We present SubMachine, a collection of web-based tools for the interactive visualization, analysis, and quantitative comparison of global-scale data sets of the Earth's interior. SubMachine focuses on making regional and global-scale seismic tomography models easily accessible to the wider solid Earth community, in order to facilitate collaborative exploration. We have written software tools to visualize and explore over 30 tomography models-individually, side-by-side, or through statistical and averaging tools. SubMachine also serves various nontomographic data sets that are pertinent to the interpretation of mantle structure and complement the tomographies. These include plate reconstruction models, normal mode observations, global crustal structure, shear wave splitting, as well as geoid, marine gravity, vertical gravity gradients, and global topography in adjustable degrees of spherical harmonic resolution. By providing repository infrastructure, SubMachine encourages and supports community contributions via submission of data sets or feedback on the implemented toolkits.