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Accessible seafloor minerals located near mid-ocean ridges are noticed to mitigate the projected metal demands of the net-zero energy transition, promoting growing interest in quantifying the global distributions of seafloor massive sulfides (SMS). Mineral potentials are commonly estimated using geophysical and geological data that lastly rely on additional confirmation studies using sparsely available, locally limited, seafloor imagery, grab samples, and coring data. This raises the challenge of linking in situ confirmation data to geophysical data acquired at disparate spatial scales to obtain quantitative mineral predictions. Although multivariate data sets for marine mineral research are incessantly acquired, robust, integrative data analysis requires cumbersome workflows and experienced interpreters. We introduce an automated two-step machine learning approach that integrates the mound detection through image segmentation with geophysical data. SMS predictors are subsequently clustered into distinct classes to infer marine mineral potentials that help guide future exploration. The automated workflow employs a U-Net convolutional neural network to identify mound structures in bathymetry data and distinguishes different mound classes through the classification of mound architectures and magnetic signatures. Finally, controlled source electromagnetic data are utilized together with in situ sampling data to reassess predictions of potential SMS volumes. Our study focuses on the Trans-Atlantic Geotraverse area, which is among the most explored SMS areas worldwide and includes 15 known SMS sites. The automated workflow classifies 14 of the 15 known mounds as exploration targets of either high or medium priority. This reduces the exploration area to less than 7% of the original survey area from 49 to 3.1 km2.

We present porosity and free gas estimations and their uncertainties at anactive methane venting site in the UK sector of the North Sea. In the Scan-ner Pockmark area in about 150m water depth, we performed a multi-disciplinary experiment to investigate the physical properties of fluid flowstructures within unconsolidated glaciomarine sediments. Here we focus onthe towed controlled source electromagnetic (CSEM) data analysis with con-straints from seismic reflection and core logging data. Inferred backgroundresistivity values vary between 0.6–1 Ωm at the surface and 1.9–2.4 Ωm at150 mbsf. We calibrate Archie’s parameters with measurements on cores, andestimate porosities of about 50±10% at the seafloor decreasing to 25±3% at 150 mbsf which matches variations expected for mechanical compaction ofclay rich sediments. High reflectivity in seismic reflection data is consistentwith the existence of a gas pocket. A synthetic study of varying gas contentin this gas pocket shows that at least 33±8% of free gas are required to causea distinct CSEM data anomaly. Real data inversions with seismic constraintssupport the presence of up to 34±14% free gas in a 30–40 m thick gas pocketunderneath the pockmark within the stratigraphic highs of a till layer abovethe glacial unconformity in the Aberdeen Ground Formation.

Evaluation of seismic reflection data has identified the presence of fluid escape structures cross-cutting overburden stratigraphy within sedimentary basins globally. Seismically-imaged chimneys/pipes are considered to be possible pathways for fluid flow, which may hydraulically connect deeper strata to the seabed. These fluid migration pathways through the overburden must be constrained to enable secure, long-term subsurface carbon dioxide (CO2) storage. We have investigated a site of natural active fluid escape in the North Sea, the Scanner Pockmark Complex, to determine the physical characteristics of focused fluid conduits, and how they control fluid flow. Here we show that a multi-scale, multi disciplinary experimental approach is required for complete characterisation of fluid escape structures. Geophysical techniques are necessary to resolve fracture geometry and subsurface structure (e.g., multifrequency seismics) and physical parameters of sediments (e.g., controlled source electromagnetics) across length scales (m to km). At smaller (mm to cm) scales, sediment cores were sampled directly and their physical and chemical properties assessed using laboratory-based methods. Numerical modelling approaches bridge the resolution gap, though their validity is dependent on calibration and constraint from field and laboratory experimental data. Further, time-lapse seismic and acoustic methods capable of resolving temporal changes are key for determining fluid flux. Future optimisation of experiment resource use may be facilitated by the installation of permanent seabed infrastructure, and replacement of manual data processing with automated workflows. This study can be used to inform measurement, monitoring and verification workflows that will assist policymaking, regulation, and best practice for CO2 subsurface storage operations.

Offshore groundwater systems have been suggested as unconventionalsources of portable water in islands and densely populated coastal regions, where terrestrial groundwater resources are over-extracted or contaminated. In this study, we evaluate how well pore-water salinity can be efficiently estimated from controlled-source electromagnetic (CSEM) resistivity models. Time-domain CSEM methods are an effective tool to explore offshore groundwater bodies since the electrical resistivity of the seafloor is primarily determined by the characteristics of the pore-water within the sub-surface sediments. We integrate offshore TD-CSEM data with borehole data and multichannel seismic reflection to identify an offshore groundwater system in the Canterbury Bight. The Canterbury margin is located off the eastern coast of the South Island of New Zealand and was previously investigated during IODP Expedition 317 in which a pore-fluid salinity anomaly was recorded in borehole U1353. By focusing on the low-salinity zone, we carry out synthetic modelling, implement Bayesian inversion to derive probability density functions for resistivity as a function of depth, and finally transform it to distribution of probability density for pore-fluid salinity using Archie’s equation. Subsequently, we use a trans-dimensional Bayesian inversion to interpret measured CSEM data, and consequently use the derived probability density functions to estimate uncertainty of pore-water salinity. Having done the same procedure for different waypoints in the Canterbury Bight, we extrapolate salinity values on a basin scale and estimate the probability density distribution for pore-water salinity as a function of depth. We show that using the Bayesian sampling algorithm provides us with a more precise estimation of hydrogeological model parameters with their uncertainties by generating an ensemble of models instead of inferring only one model using deterministic inversion approaches.

Since 1945, when the International Military Tribunal conducted the trials of the major Nazi war criminals in Nuremberg effective interpretation has been the essential communication mechanism amongst multilingual courtroom participants: court administration, lawyers and judges, and war crimes perpetrators, victims and witnesses. As such, interpreting has been crucial in domestic trials of WWII criminals, such as the 1961 Eichmann trial; the 1989 Demjanjuk trial (Morris 1989, 1998), the 1986-1993 Australian War Crimes Prosecutions (Fraser 2010; Stern 1995), and also in the more recent war crimes trials by international courts and tribunals, including the UN International Criminal Tribunals for the Former Yugoslavia and Rwanda (ICTY and ICTR respectively), and the permanent International Criminal Court (ICC). These recent war crimes trials have brought together two different legal worlds: that of the western-style, mainly English- and French-speaking courts (domestic courts, ICTY, ICTR and ICC), on the one hand, and on the other that of victims, witnesses and perpetrators who mostly speak the ‘rare’ languages of the countries of conflict, some existing only as vernacular (African tribal languages Lingala, Sango, Acholi) or regional language varieties (Russian/Ukrainian dialects, languages of the former Yugoslavia, French and English African varieties, Swahili in the Congo). In this complex multilingual and multicultural legal environment proceedings rely on accurate provision of evidence about major war crimes. The question I address here is this: what challenges do court interpreters experience when dealing with war crimes related evidence, and how do participants from radically opposed cultural and legal backgrounds achieve mutual understanding?Interestingly, irrespective of interpreting practice and quality, war crimes trials over the years have revealed similarities in the types of interpreting challenges (Stern 1995, 2001, 2004, 2011). Some problems of cross-lingu

Highlights • Joint seismic, CSEM and geochemical estimate of gas and hydrate saturation. • Converted shear wave analyses for gas hydrate distribution. • Wide angle full waveform inversion. • Paleo-BSRs and gas hydrate system in disequilibrium. • Numerical framework for joint inversion of multiple geophysical methods. Abstract Gas hydrates are naturally-occurring solid compounds of gas and water within almost all sediment-rich continental margins. Due to the large amounts of methane stored in submarine gas hydrates, they might serve as future reservoirs for offshore marine gas production. Assessing the reservoir characteristics requires reliable estimates of both the gas and gas hydrate concentration, which can be best addressed using geophysical and geological investigations. Here, we demonstrate the power of joint interpretation of interdisciplinary geophysical techniques and geological laboratory experiments. Regional 2D multichannel seismic data provide the broad overview of a hydrate-bearing area. High-resolution 2D and 3D seismic reflection data provide detailed images of two working areas, the buried S1 channel-levee system at 1500 m water depth (well within the gas hydrate stability zone) and a slope failure location, located at 665 m water depth (top limit of the hydrate formation) next to the S2 channel. Detailed compressional and shear wave (Vs) velocity-depth models were derived from four component ocean-bottom seismic data, the latter from P- to S-conversion upon reflection. Due to their steep reflection angles, shear wave events result in less resolved Vs models. Nevertheless, in case of a change in elasticity of the sediment matrix due to gas hydrate cementation, shear wave events can be used as an indicator. As such, Vs can give insight into the nature of hydrate formation throughout the GHSZ. We present new developments in the application of common reflection surface, normal-incidence-point tomography and full waveform inversion techniques to enhance

Seafloor massive sulfide (SMS) deposits are of increasing economic interest in order to satisfy the relentless growth in worldwide metal demand. The Trans‐Atlantic Geotraverse (TAG) hydrothermal field at 26°N on the Mid‐Atlantic Ridge hosts several such deposits. This study presents new controlled source electromagnetic, bathymetric, and magnetic results from the TAG field. Potential SMS targets were selected based on their surface expressions in high‐resolution bathymetric data. High‐resolution reduced‐to‐the‐pole magnetic data show negative anomalies beneath and surrounding the SMS deposits, revealing large areas of hydrothermal alteration. Controlled source electromagnetic data, sensitive to the electrical conductivity of SMS mineralization, further reveal a maximum thickness of up to 80 m and conductivities of up to 5 S/m. SMS samples have conductivities of up to a few thousand Siemens per meter, suggesting that remotely inferred conductivities represent an average of metal sulfide ores combined with silicified and altered host basalt that likely dominates at greater depths.

This paper applies nonlinear Bayesian inversion to marine controlled source electromagnetic (CSEM) data collected near two sites of the Integrated Ocean Drilling Program (IODP) Expedition 311 on the northern Cascadia Margin to investigate subseafloor resistivity structure related to gas hydrate deposits and cold vents. The Cascadia margin, off the west coast of Vancouver Island, Canada, has a large accretionary prism where sediments are under pressure due to convergent plate boundary tectonics. Gas hydrate deposits and cold vent structures have previously been investigated by various geophysical methods and seabed drilling. Here, we invert time-domain CSEM data collected at Sites U1328 and U1329 of IODP Expedition 311 using Bayesian methods to derive subsurface resistivity model parameters and uncertainties. The Bayesian information criterion is applied to determine the amount of structure (number of layers in a depth-dependent model) that can be resolved by the data. The parameter space is sampled with the Metropolis–Hastings algorithm in principal-component space, utilizing parallel tempering to ensure wider and efficient sampling and convergence. Nonlinear inversion allows analysis of uncertain acquisition parameters such as time delays between receiver and transmitter clocks as well as input electrical current amplitude. Marginalizing over these instrument parameters in the inversion accounts for their contribution to the geophysical model uncertainties. One-dimensional inversion of time-domain CSEM data collected at measurement sites along a survey line allows interpretation of the subsurface resistivity structure. The data sets can be generally explained by models with 1 to 3 layers. Inversion results at U1329, at the landward edge of the gas hydrate stability zone, indicate a sediment unconformity as well as potential cold vents which were previously unknown. The resistivities generally increase upslope due to sediment erosion along the slope. Inversion resul

Zero Dark Thirty (Kathryn Bigelow 2012) has given rise to much critical debate, focused primarily on its questionable historical accuracy, apparent political perspective and the extent to which its narrative condones torture as an instrument of intelligence gathering. These are indisputably important issues, however they have tended to crowd out of the critical agenda alternative approaches to the film, two of which I would like to address in this chapter. From a feminist perspective, one of the most striking features of Zero Dark Thirty is the use of a female lead in such a consistently ‘masculine’ genre as the war film. Critical reaction has inevitably been mixed. Some commentators celebrate Maya as a new feminist icon, some position her as a post-feminist, gender-neutral figure, while others take a more sceptical stance, seeing her presence as providing a form of ideological camouflage for US militarism, ultimately reinforcing a patriarchal status quo. But there has been little by way of sustained analysis of her role in the film. Another striking feature of this film is the extent to which it articulates the relationship between cinema and war proposed by Paul Virilio. The intradiegetic use of surveillance technology exemplifies the ‘logistics of perception’ discussed in The Vision Machine, while the appropriation of the ‘reality effect’ of mediated images for the purposes of a Hollywood film speaks to Virilio’s ‘aesthetics of disappearance’. I would like to address both these perspectives, arguing that there is in fact a close relationship between them. The gender of the protagonist is much more than an incidental detail within the film, having profound implications for the structure and dynamics of the narrative. Without a female protagonist, the central dramatic device of surveillance-as-action and the effective exclusion of the hero from direct engagement in the climatic “battle” (the moment for which the film is named) would be problematic, if not impossibl