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The northern Red Sea coastal ecosystem is one of the most diverse coastal ecosystems in the world. Fortunately, it has shown extraordinary resilience against climate change and is predicted to survive global warming during the coming decades. However, with warming waters, increased sediment and pollutants, and other human impacts, the ecosystem and consequently thriving reef tourism which forms a pillar of the ongoing economic diversification policies of the northern Red Sea region are under threat. A variety of evidence indicates significant damage has already been done to terrestrial and ocean ecosystems on both sides of the northern Red Sea. Expenditures on ecosystem protection and research lag behind Egypt's billions in USD revenue from tourism. Unfortunately, the economic drive to generate profit has resulted in sprawling touristic, industrial, and mixed development without careful planning or assessment of the fragility and sustainability of the natural ecosystem. As a result, the future of coastal urban growth is murky. Given its natural, social, and touristic value, the northern Red Sea system requires a special ecological security system with detailed analysis, inclusive development, and proactive governance across coastal cities and their adjacent inland secondary cities. This study identifies the geological research gaps, human-ecological interactions, inclusive urban development challenges, and related literature pertaining to the northern Red Sea. We propose immediate, targeted, multidisciplinary research trajectories and provide policy recommendations to ensure that the region's existing and future developmental pursuits are undertaken in an environmentally sustainable and inclusive approach.

Volcanic islands export clastic material to their surrounding oceans by explosive eruptions, lava emissions, biogenic production on their shelves, and failure of their slopes, amongst other processes. This raises the question of whether geological events (in particular, eruptions and landslides) can be detected offshore and dated, and whether any relationships (for example, with climate changes) can be revealed using sediment cores. The volcanically active central Azorean islands (Faial, Pico, São Jorge, and Terceira), with their neighboring submarine basins, are potentially good candidates for such an analysis. Here, chronostratigraphies of four gravity cores collected amongst the islands are constructed based on twelve radiocarbon dates and two dates derived by geochemically correlating primary volcaniclastic turbidites with ignimbrites on Faial and Terceira Islands. Age-depth models are built from the hemipelagic intervals to estimate individual turbidite dates. Volumes of turbidites are modeled by multiplying basin areas with bed thickness, allowing for various turbidite thinning rates and directions. The volumes of landslide-generated turbidites are only comparable with the largest volumes of their adjacent upper-slope submarine landslide valleys; therefore, such turbidites in the cores likely derive from these largest landslides. Emplacement intervals between turbidites originating from both landslides and pyroclastic density currents are found to be mostly a few thousand years. Frequencies of landslide-generated turbidites and hemipelagic sedimentation rates were both highest in the past 8 k.y. compared to preceding periods up to 50 k.y. High hemipelagic sedimentation rates are interpreted to be related to sea-level rise, allowing more shelf bioproduction and release of particles by coastal erosion. The coincident increased frequencies of submarine landslides may also be associated with the increased sediment supply from the islands, resulting in a more rapid

Geological histories of volcanic ocean islands can be revealed by the sediments shed by them. Hence there is an interest in studying cores of volcaniclastic sediments that are particularly preserved in the many flat-floored basins lying close to the Azores islands. We analyse four gravity cores collected around the central group of the islands. Three sedimentary facies (F1-F2a, F2b) are recognized based on visual core logging, particle morphometric and geochemical analyses. F1 is clay-rich hemipelagite comprising homogeneous mud with mottled structures from bioturbation. F2a and F2b are both clay-poor volcaniclastic deposits, which are carbonate-rich and carbonate-poor, respectively. More biogenic carbonate in F2a reflects the incorporation of unconsolidated calcareous material from island shelves or bioturbation. Within F2a and F2b we identify deposits emplaced by pyroclastic fallout, primary or secondary turbidity currents by combining multiple information from lithological composition, sedimentary structures, chemical composition of volcanic glass shards and morphometric characteristics of volcanic particles. Primary volcaniclastic sediments were found in all four cores, echoing activity known to have occurred up to historical times on the adjacent islands. These preliminary results suggest that greater details of geological events could be inferred for other volcanic islands by adopting a similar approach to core analysis.

Volcanic islands export clastic material to their surrounding oceans by explosive eruptions, lava emissions, biogenic production on their shelves, and failure of their slopes, amongst other processes. This raises the question of whether geological events (in particular, eruptions and landslides) can be detected offshore and dated, and whether any relationships (for example, with climate changes) can be revealed using sediment cores. The volcanically active central Azorean islands (Faial, Pico, São Jorge, and Terceira), with their neighboring submarine basins, are potentially good candidates for such an analysis. Here, chronostratigraphies of four gravity cores collected amongst the islands are constructed based on twelve radiocarbon dates and two dates derived by geochemically correlating primary volcaniclastic turbidites with ignimbrites on Faial and Terceira Islands. Age-depth models are built from the hemipelagic intervals to estimate individual turbidite dates. Volumes of turbidites are modeled by multiplying basin areas with bed thickness, allowing for various turbidite thinning rates and directions. The volumes of landslide-generated turbidites are only comparable with the largest volumes of their adjacent upper-slope submarine landslide valleys; therefore, such turbidites in the cores likely derive from these largest landslides. Emplacement intervals between turbidites originating from both landslides and pyroclastic density currents are found to be mostly a few thousand years. Frequencies of landslide-generated turbidites and hemipelagic sedimentation rates were both highest in the past 8 k.y. compared to preceding periods up to 50 k.y. High hemipelagic sedimentation rates are interpreted to be related to sea-level rise, allowing more shelf bioproduction and release of particles by coastal erosion. The coincident increased frequencies of submarine landslides may also be associated with the increased sediment supply from the islands, resulting in a more rapid

The Red Sea is an important example of a continental rift transitioning slowly to an oceanic basin. However, structures that can inform us of how that transition occurred have been poorly reported because deep seismic reflection data capable of imaging basement under the rift sediments are generally lacking publicly. Three lines of multichannel seismic reflection data have recently been published revealing structures on the Nubian side of the central part of the basin. In this study, we reassess these data in the light of recent studies of the central Red Sea. Over continental crust, the data reveal reflection sequences likely due to strata at or near the base of the evaporites, in two cases with varied dips suggesting the presence of syn-rift growth stratigraphy. Almost all of those reflections dip downwards towards the rift axis, not away as would be expected from tilted fault blocks of bookshelf faulting types. That observation, and low relief of basement, confirm inferences made earlier based on gravity anomalies that this part of the Red Sea lacks large-relief fault escarpments and is most likely a syn-rift sag basin. In the transition to oceanic crust, an abnormally broad magnetic anomaly of estimated Chron 5 age is found not to be associated with structures such as sills, so it likely arises from deeper sources. One of the seismic lines traverses a ridge in Bouguer gravity anomalies that runs across the axis. This feature has previously been interpreted as a volcanic ridge similar to those observed at other ultra-slow spreading ridges. The seismic data reveal diffuse basement reflections and confirm that the record immediately above basement lacks reflections typical of sedimentary strata. Both observations are consistent with the presence of oceanic crust. Modelling of gravity anomalies suggests the ridge is likely underlain by igneous intrusive rocks displacing mantle rocks, as expected for a volcanic ridge. The seismic data, combined with recently updated

The Red Sea is an important example of a continental rift transitioning slowly to an oceanic basin. However, structures that can inform us of how that transition occurred have been poorly reported because deep seismic reflection data capable of imaging basement under the rift sediments are generally lacking publicly. Three lines of multichannel seismic reflection data have recently been published revealing structures on the Nubian side of the central part of the basin. In this study, we reassess these data in the light of recent studies of the central Red Sea. Over continental crust, the data reveal reflection sequences likely due to strata at or near the base of the evaporites, in two cases with varied dips suggesting the presence of syn-rift growth stratigraphy. Almost all of those reflections dip downwards towards the rift axis, not away as would be expected from tilted fault blocks of bookshelf faulting types. That observation, and low relief of basement, confirm inferences made earlier based on gravity anomalies that this part of the Red Sea lacks large-relief fault escarpments and is most likely a syn-rift sag basin. In the transition to oceanic crust, an abnormally broad magnetic anomaly of estimated Chron 5 age is found not to be associated with structures such as sills, so it likely arises from deeper sources. One of the seismic lines traverses a ridge in Bouguer gravity anomalies that runs across the axis. This feature has previously been interpreted as a volcanic ridge similar to those observed at other ultra-slow spreading ridges. The seismic data reveal diffuse basement reflections and confirm that the record immediately above basement lacks reflections typical of sedimentary strata. Both observations are consistent with the presence of oceanic crust. Modelling of gravity anomalies suggests the ridge is likely underlain by igneous intrusive rocks displacing mantle rocks, as expected for a volcanic ridge. The seismic data, combined with recently updated

Distributed ledger technologies, also known as blockchains for enterprises, promise to significantly reduce the high cost of automating multi-party business workflows. We argue that a programming language for writing such on-ledger logic should satisfy three desiderata: (1) Provide concepts to capture the legal rules that govern real-world business workflows. (2) Include simple means for specifying policies for access and authorization. (3) Support the composition of simple workflows into complex ones, even when the simple workflows have already been deployed. We present the open-source smart contract language Daml based on Haskell with strict evaluation. Daml achieves these desiderata by offering novel primitives for representing, accessing, and modifying data on the ledger, which are mimicking the primitives of today's legal systems. Robust access and authorization policies are specified as part of these primitives, and Daml's built-in authorization rules enable delegation, which is key for workflow composability. These properties make Daml well-suited for orchestrating business workflows across multiple, otherwise heterogeneous parties. Daml contracts run (1) on centralized ledgers backed by a database, (2) on distributed deployments with Byzantine fault tolerant consensus, and (3) on top of conventional blockchains, as a second layer via an atomic commit protocol.

Volcanic islands export clastic material to their surrounding oceans by explosive eruptions, lava emissions, biogenic production on their shelves, and failure of their slopes, amongst other processes. This raises the question of whether geological events (in particular, eruptions and landslides) can be detected offshore and dated, and whether any relationships (for example, with climate changes) can be revealed using sediment cores. The volcanically active central Azorean islands (Faial, Pico, São Jorge, and Terceira), with their neighboring submarine basins, are potentially good candidates for such an analysis. Here, chronostratigraphies of four gravity cores collected amongst the islands are constructed based on twelve radiocarbon dates and two dates derived by geochemically correlating primary volcaniclastic turbidites with ignimbrites on Faial and Terceira Islands. Age-depth models are built from the hemipelagic intervals to estimate individual turbidite dates. Volumes of turbidites are modeled by multiplying basin areas with bed thickness, allowing for various turbidite thinning rates and directions. The volumes of landslide-generated turbidites are only comparable with the largest volumes of their adjacent upper-slope submarine landslide valleys; therefore, such turbidites in the cores likely derive from these largest landslides. Emplacement intervals between turbidites originating from both landslides and pyroclastic density currents are found to be mostly a few thousand years. Frequencies of landslide-generated turbidites and hemipelagic sedimentation rates were both highest in the past 8 k.y. compared to preceding periods up to 50 k.y. High hemipelagic sedimentation rates are interpreted to be related to sea-level rise, allowing more shelf bioproduction and release of particles by coastal erosion. The coincident increased frequencies of submarine landslides may also be associated with the increased sediment supply from the islands, resulting in a more rapid

Volcanic islands export clastic material to their surrounding oceans by explosive eruptions, lava emissions, biogenic production on their shelves, and failure of their slopes, amongst other processes. This raises the question of whether geological events (in particular, eruptions and landslides) can be detected offshore and dated, and whether any relationships (for example, with climate changes) can be revealed using sediment cores. The volcanically active central Azorean islands (Faial, Pico, São Jorge, and Terceira), with their neighboring submarine basins, are potentially good candidates for such an analysis. Here, chronostratigraphies of four gravity cores collected amongst the islands are constructed based on twelve radiocarbon dates and two dates derived by geochemically correlating primary volcaniclastic turbidites with ignimbrites on Faial and Terceira Islands. Age-depth models are built from the hemipelagic intervals to estimate individual turbidite dates. Volumes of turbidites are modeled by multiplying basin areas with bed thickness, allowing for various turbidite thinning rates and directions. The volumes of landslide-generated turbidites are only comparable with the largest volumes of their adjacent upper-slope submarine landslide valleys; therefore, such turbidites in the cores likely derive from these largest landslides. Emplacement intervals between turbidites originating from both landslides and pyroclastic density currents are found to be mostly a few thousand years. Frequencies of landslide-generated turbidites and hemipelagic sedimentation rates were both highest in the past 8 k.y. compared to preceding periods up to 50 k.y. High hemipelagic sedimentation rates are interpreted to be related to sea-level rise, allowing more shelf bioproduction and release of particles by coastal erosion. The coincident increased frequencies of submarine landslides may also be associated with the increased sediment supply from the islands, resulting in a more rapid

Volcanic islands export clastic material to their surrounding oceans by explosive eruptions, lava emissions, biogenic production on their shelves, and failure of their slopes, amongst other processes. This raises the question of whether geological events (in particular, eruptions and landslides) can be detected offshore and dated, and whether any relationships (for example, with climate changes) can be revealed using sediment cores. The volcanically active central Azorean islands (Faial, Pico, São Jorge, and Terceira), with their neighboring submarine basins, are potentially good candidates for such an analysis. Here, chronostratigraphies of four gravity cores collected amongst the islands are constructed based on twelve radiocarbon dates and two dates derived by geochemically correlating primary volcaniclastic turbidites with ignimbrites on Faial and Terceira Islands. Age-depth models are built from the hemipelagic intervals to estimate individual turbidite dates. Volumes of turbidites are modeled by multiplying basin areas with bed thickness, allowing for various turbidite thinning rates and directions. The volumes of landslide-generated turbidites are only comparable with the largest volumes of their adjacent upper-slope submarine landslide valleys; therefore, such turbidites in the cores likely derive from these largest landslides. Emplacement intervals between turbidites originating from both landslides and pyroclastic density currents are found to be mostly a few thousand years. Frequencies of landslide-generated turbidites and hemipelagic sedimentation rates were both highest in the past 8 k.y. compared to preceding periods up to 50 k.y. High hemipelagic sedimentation rates are interpreted to be related to sea-level rise, allowing more shelf bioproduction and release of particles by coastal erosion. The coincident increased frequencies of submarine landslides may also be associated with the increased sediment supply from the islands, resulting in a more rapid

Geological histories of volcanic ocean islands can be revealed by the sediments shed by them. Hence there is an interest in studying cores of volcaniclastic sediments that are particularly preserved in the many flat-floored basins lying close to the Azores islands. We analyse four gravity cores collected around the central group of the islands. Three sedimentary facies (F1-F2a, F2b) are recognized based on visual core logging, particle morphometric and geochemical analyses. F1 is clay-rich hemipelagite comprising homogeneous mud with mottled structures from bioturbation. F2a and F2b are both clay-poor volcaniclastic deposits, which are carbonate-rich and carbonate-poor, respectively. More biogenic carbonate in F2a reflects the incorporation of unconsolidated calcareous material from island shelves or bioturbation. Within F2a and F2b we identify deposits emplaced by pyroclastic fallout, primary or secondary turbidity currents by combining multiple information from lithological composition, sedimentary structures, chemical composition of volcanic glass shards and morphometric characteristics of volcanic particles. Primary volcaniclastic sediments were found in all four cores, echoing activity known to have occurred up to historical times on the adjacent islands. These preliminary results suggest that greater details of geological events could be inferred for other volcanic islands by adopting a similar approach to core analysis.

Geological histories of volcanic ocean islands can be revealed by the sediments shed by them. Hence there is an interest in studying cores of volcaniclastic sediments that are particularly preserved in the many flat-floored basins lying close to the Azores islands. We analyse four gravity cores collected around the central group of the islands. Three sedimentary facies (F1-F2a, F2b) are recognized based on visual core logging, particle morphometric and geochemical analyses. F1 is clay-rich hemipelagite comprising homogeneous mud with mottled structures from bioturbation. F2a and F2b are both clay-poor volcaniclastic deposits, which are carbonate-rich and carbonate-poor, respectively. More biogenic carbonate in F2a reflects the incorporation of unconsolidated calcareous material from island shelves or bioturbation. Within F2a and F2b we identify deposits emplaced by pyroclastic fallout, primary or secondary turbidity currents by combining multiple information from lithological composition, sedimentary structures, chemical composition of volcanic glass shards and morphometric characteristics of volcanic particles. Primary volcaniclastic sediments were found in all four cores, echoing activity known to have occurred up to historical times on the adjacent islands. These preliminary results suggest that greater details of geological events could be inferred for other volcanic islands by adopting a similar approach to core analysis.

International 'naming and shaming' campaigns rely on domestic civil society organizations (CSOs) for information on local human rights conditions. To stop this flow of information, some governments restrict CSOs, for example by limiting their access to funding. Do such restrictions reduce international naming and shaming campaigns that rely on information from domestic CSOs? This article argues that on the one hand, restrictions may reduce CSOs' ability and motives to monitor local abuses. On the other hand, these organizations may mobilize against restrictions and find new ways of delivering information on human rights violations to international publics. Using a cross-national dataset and in-depth evidence from Egypt, the study finds that low numbers of restrictions trigger shaming by international non-governmental organizations. Yet once governments impose multiple types of restrictions, it becomes harder for CSOs to adapt, resulting in fewer international shaming campaigns.

Highlights • Red Sea salt deposits are loaded by only 200–300 m hemipelagics in deep water • Internal growth stratigraphy shows that they were deforming while being deposited • Power spectra of their surface shows they are inverse power-law over 1–13 km scale • Variograms suggest that their surface is stochastic with average lengthscale of ~3 km • Their stochastic character rules out Rayleigh-Taylor models of diapirism here Rayleigh-Taylor models for diapirism predict that diapirs should develop with characteristic spacings, whereas other models predict varied spacings. The deep-water Miocene evaporites in the Red Sea provide a useful opportunity to quantify length scales of diapirism to compare with model predictions. We first review the stratigraphy of the uppermost evaporites in high-resolution seismic data, revealing tectonic growth stratigraphy indicating that halokinetic movements occurred while the evaporites were being deposited. In some places, movements continued after the Miocene evaporite phase. The S-reflection marking the top of the evaporites is an erosional surface, in places, truncating anticlines of layered evaporites. In others, reflections within the uppermost evaporites are conformable, suggesting a lack of erosion. The top of the evaporites therefore had relief at the end of the Miocene. We select for numerical analysis 14 long profiles of topography of the S-reflection. Variograms derived from them after detrending reveal minor periodicity, though with varied wavelength, and varied roughness of the surface. However, an average variogram computed from these profiles is nearly exponential, indicating that the evaporite surface is mostly stochastic with no uniform scale of diapirism. An exponential model fitted to that average variogram suggests a spatial range over which the S-reflection topography becomes decorrelated of 3 km, which is comparable with the mean vertical thickness of the evaporite body. Power spectra of the evaporite surface are

Pro-government militias are a prominent feature of civil wars. Governments in Ukraine, Russia, Syria, and Sudan recruit irregular forces in their armed struggle against insurgents. The United States collaborated with Awakening groups to counter the insurgency in Iraq, just as colonizers used local armed groups to fight rebellions in their colonies. A now quite wide and established cross-disciplinary literature on pro-government nonstate armed groups has generated a variety of research questions for scholars interested in conflict, political violence, and political stability: Does the presence of such groups indicate a new type of conflict? What are the dynamics that drive governments to align with informal armed groups and that make armed groups choose to side with the government? Given the risks entailed in surrendering a monopoly of violence, is there a turning point in a conflict when governments enlist these groups? How successful are these groups? Why do governments use these nonstate armed actors to shape foreign conflicts, whether as insurgents or counterinsurgents abroad? Are these nonstate armed actors always useful to governments or perhaps even an indicator of state failure? How do pro-government militias affect the safety and security of civilians? The enduring pattern of collaboration between governments and pro-government armed groups challenges conventional theory and the idea of an evolutionary process of the modern state consolidating the means of violence. Research on these groups and their consequences began with case studies, and these continue to yield valuable insights. More recently, survey work and cross-national quantitative research have contributed to our knowledge. This mix of methods is opening new lines of inquiry for research on insurgencies and the delivery of the core public good of effective security.

Build systems are a fundamental part of software construction, but their correctness has received comparatively little attention, relative to more prominent parts of the toolchain. In this paper, we address the correctness of \emph{forward build systems}, which automatically determine the dependency structure of the build, rather than having it specified by the programmer. We first define what it means for a forward build system to be correct -- it must behave identically to simply executing the programmer-specified commands in order. Of course, realistic build systems avoid repeated work, stop early when possible, and run commands in parallel, and we prove that these optimizations, as embodied in the recent forward build system \textsc{Rattle}, preserve our definition of correctness. Along the way, we show that other forward build systems, such as \textsc{Fabricate} and \textsc{Memoize}, are also correct. We carry out all of our work in \Agda, and describe in detail the assumptions underlying both \textsc{Rattle} itself and our modeling of it., Comment: CPP 2022: Proceedings of the 11th ACM SIGPLAN International Conference on Certified Programs and Proofs

Highlights • Red Sea salt deposits are loaded by only 200–300 m hemipelagics in deep water • Internal growth stratigraphy shows that they were deforming while being deposited • Power spectra of their surface shows they are inverse power-law over 1–13 km scale • Variograms suggest that their surface is stochastic with average lengthscale of ~3 km • Their stochastic character rules out Rayleigh-Taylor models of diapirism here Rayleigh-Taylor models for diapirism predict that diapirs should develop with characteristic spacings, whereas other models predict varied spacings. The deep-water Miocene evaporites in the Red Sea provide a useful opportunity to quantify length scales of diapirism to compare with model predictions. We first review the stratigraphy of the uppermost evaporites in high-resolution seismic data, revealing tectonic growth stratigraphy indicating that halokinetic movements occurred while the evaporites were being deposited. In some places, movements continued after the Miocene evaporite phase. The S-reflection marking the top of the evaporites is an erosional surface, in places, truncating anticlines of layered evaporites. In others, reflections within the uppermost evaporites are conformable, suggesting a lack of erosion. The top of the evaporites therefore had relief at the end of the Miocene. We select for numerical analysis 14 long profiles of topography of the S-reflection. Variograms derived from them after detrending reveal minor periodicity, though with varied wavelength, and varied roughness of the surface. However, an average variogram computed from these profiles is nearly exponential, indicating that the evaporite surface is mostly stochastic with no uniform scale of diapirism. An exponential model fitted to that average variogram suggests a spatial range over which the S-reflection topography becomes decorrelated of 3 km, which is comparable with the mean vertical thickness of the evaporite body. Power spectra of the evaporite surface are

Geological histories of volcanic ocean islands can be revealed by the sediments shed by them. Hence there is an interest in studying cores of volcaniclastic sediments that are particularly preserved in the many flat-floored basins lying close to the Azores islands. We analyse four gravity cores collected around the central group of the islands. Three sedimentary facies (F1-F2a, F2b) are recognized based on visual core logging, particle morphometric and geochemical analyses. F1 is clay-rich hemipelagite comprising homogeneous mud with mottled structures from bioturbation. F2a and F2b are both clay-poor volcaniclastic deposits, which are carbonate-rich and carbonate-poor, respectively. More biogenic carbonate in F2a reflects the incorporation of unconsolidated calcareous material from island shelves or bioturbation. Within F2a and F2b we identify deposits emplaced by pyroclastic fallout, primary or secondary turbidity currents by combining multiple information from lithological composition, sedimentary structures, chemical composition of volcanic glass shards and morphometric characteristics of volcanic particles. Primary volcaniclastic sediments were found in all four cores, echoing activity known to have occurred up to historical times on the adjacent islands. These preliminary results suggest that greater details of geological events could be inferred for other volcanic islands by adopting a similar approach to core analysis.

With the first tokamak designed for full nuclear operation now well into final assembly (ITER), and a major new research tokamak starting commissioning (JT60SA), nuclear fusion is becoming a mainstream potential energy source for the future. A critical part of the viability of magnetic confinement for fusion is superconductor technology. The experience gained and lessons learned in the application of this technology to ITER and JT60SA, together with new and improved superconducting materials, is opening multiple routes to commercial fusion reactors. The objective of this roadmap is, through a series of short articles, to outline some of these routes and the materials/technologies that go with them.

With the first tokamak designed for full nuclear operation now well into final assembly (ITER), and a major new research tokamak starting commissioning (JT60SA), nuclear fusion is becoming a mainstream potential energy source for the future. A critical part of the viability of magnetic confinement for fusion is superconductor technology. The experience gained and lessons learned in the application of this technology to ITER and JT60SA, together with new and improved superconducting materials, is opening multiple routes to commercial fusion reactors. The objective of this roadmap is, through a series of short articles, to outline some of these routes and the materials/technologies that go with them.

International ‘naming and shaming’ campaigns rely on domestic civil society organizations (CSOs) for information on local human rights conditions. To stop this flow of information, some governments restrict CSOs, for example by limiting their access to funding. Do such restrictions reduce international naming and shaming campaigns that rely on information from domestic CSOs? This article argues that on the one hand, restrictions may reduce CSOs’ ability and motives to monitor local abuses. On the other hand, these organizations may mobilize against restrictions and find new ways of delivering information on human rights violations to international publics. Using a cross-national dataset and in-depth evidence from Egypt, the study finds that low numbers of restrictions trigger shaming by international non-governmental organizations. Yet once governments impose multiple types of restrictions, it becomes harder for CSOs to adapt, resulting in fewer international shaming campaigns.

Build scripts for most build systems describe the actions to run, and the dependencies between those actions---but often build scripts get those dependencies wrong. Most build scripts have both too few dependencies (leading to incorrect build outputs) and too many dependencies (leading to excessive rebuilds and reduced parallelism). Any programmer who has wondered why a small change led to excess compilation, or who resorted to a "clean" step, has suffered the ill effects of incorrect dependency specification. We outline a build system where dependencies are not specified, but instead captured by tracing execution. The consequence is that dependencies are always correct by construction and build scripts are easier to write. The simplest implementation of our approach would lose parallelism, but we are able to recover parallelism using speculation.

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors

Erosion of volcanic islands ultimately creates shallow banks and guyots, but the ways in which erosion proceeds to create them over time and how the coastline retreat rate relates to wave conditions, rock mass strength and other factors are unclear. The Capelinhos volcano was formed in 1957/58 during a Surtseyan and partly effusive eruption that added an ~2.5 km2 tephra and lava promontory to the western end of Faial Island (Azores, central North Atlantic). Subsequent coastal and submarine erosion has reduced the subaerial area of the promontory and created a submarine platform. This study uses historical information, photos and marine geophysical data collected around the promontory to characterize how the submarine platform developed following the eruption. Historical coastline positions are supplemented with coastlines interpreted from 2004 and 2014 Google Earth images in order to work out the progression of coastline retreat rate and retreat distance for lava‐ and tephra‐dominated cliffs. Data from swath mapping sonars are used to characterize the submarine geometry of the resulting platform (position of the platform edge, gradient and morphology of the platform surface). Photographs collected during SCUBA and ROV dives on the submarine platform reveal a rugged surface now covered with boulders. The results show that coastal retreat rates decreased rapidly with time after the eruption and approximately follow an inverse power‐law relationship with coastal retreat distance. We develop a finite‐difference model for wave attenuation over dipping surfaces to predict how increasing wave attenuation contributed to this trend. The model is verified by reproducing the wave height variation over dipping rock platforms in the UK (platform gradient 1.2° to 1.8°) and Ireland (1.8°). Applying the model to the dipping platform around Capelinhos, using a diversity of cliff resistance predicted from known lithologies, we are able to predict erosion rate trends for some sectors

Highlights • Deep seismic data reveal oceanic-like axial ridge beneath central Red Sea. • Axial high is similar to those of hotspot-affected spreading centres. • Bouguer anomalies predict low average density beneath axis. • This low density implies thickened crust and/or low mantle density. • Normal thickness predicted from Na8.0 implies recent transition from thinner crust. Abstract The Red Sea is an important example of a rifted continental shield proceeding to seafloor spreading. However, whether the crust in the central Red Sea is continental or oceanic has been controversial. Contributing to this debate, we assess the basement geometry using seismic reflection and potential field data. We find that the basement topography from seismically derived structure corrected for evaporite and other sediment loading has an axial high with a width of 70–100 km and a height of 0.8–1.6 km. Basement axial highs are commonly found at mid-ocean ridges affected by hotspots, where enhanced mantle melting results in thickened crust. We therefore interpret this axial high as oceanic-like, potentially produced by recently enhanced melting associated with the broader Afar mantle anomaly. We also find the Bouguer gravity anomalies are strongly correlated with basement reflection depths. The apparent density contrast necessary to explain the Bouguer anomaly varies from 220 kg m−3 to 580 kg m−3 with no trend with latitude. These values are too small to be caused primarily by the density contrast between evaporites and mantle across a crust of uniform thickness and density structure, further supporting a thickened crustal origin for the axial high. Complicating interpretation, only a normal to modestly thickened axial crust is predicted from fractionation-corrected sodium contents (Na8.0), and the basement reflection is rugged, more typical of ultra-slow spreading ridges that are not close to hotspots. We try to reconcile these observations with recent results from seismic tomography, w

Highlights • Deep seismic data reveal oceanic-like axial ridge beneath central Red Sea. • Axial high is similar to those of hotspot-affected spreading centres. • Bouguer anomalies predict low average density beneath axis. • This low density implies thickened crust and/or low mantle density. • Normal thickness predicted from Na8.0 implies recent transition from thinner crust. Abstract The Red Sea is an important example of a rifted continental shield proceeding to seafloor spreading. However, whether the crust in the central Red Sea is continental or oceanic has been controversial. Contributing to this debate, we assess the basement geometry using seismic reflection and potential field data. We find that the basement topography from seismically derived structure corrected for evaporite and other sediment loading has an axial high with a width of 70–100 km and a height of 0.8–1.6 km. Basement axial highs are commonly found at mid-ocean ridges affected by hotspots, where enhanced mantle melting results in thickened crust. We therefore interpret this axial high as oceanic-like, potentially produced by recently enhanced melting associated with the broader Afar mantle anomaly. We also find the Bouguer gravity anomalies are strongly correlated with basement reflection depths. The apparent density contrast necessary to explain the Bouguer anomaly varies from 220 kg m−3 to 580 kg m−3 with no trend with latitude. These values are too small to be caused primarily by the density contrast between evaporites and mantle across a crust of uniform thickness and density structure, further supporting a thickened crustal origin for the axial high. Complicating interpretation, only a normal to modestly thickened axial crust is predicted from fractionation-corrected sodium contents (Na8.0), and the basement reflection is rugged, more typical of ultra-slow spreading ridges that are not close to hotspots. We try to reconcile these observations with recent results from seismic tomography, w

Highlights • Features in GLORIA images match those in multibeam sonar data. • Salt walls suggested by lineaments in northern Red Sea. Abstract The Red Sea is an unusual example of a rift basin that transitioned from its evaporitic stage to fully open-ocean conditions at the end of the Miocene (∼5.3 Ma), much more recently than older Mesozoic margins around the Atlantic and Gulf of Mexico. The patterns of halokinetic deformation occurring in the Red Sea are potentially of interest for understanding more generally how evaporite deposits deform during this early stage. Relevant to this issue, a line of reconnaissance sidescan sonar data (GLORIA) collected along the Red Sea in 1979 is re-evaluated here. We first interpret the data with the aid of newly compiled bathymetry from multibeam sonars in the central and southern Red Sea. Features in the acoustic backscatter data are associated with ridges, valleys and rounded flow fronts produced by halokinetic deformation. Some areas of higher acoustic backscattering from the evaporites are suggested to relate to roughness produced by deformation of the evaporite surface. Within the volcanic (oceanic) axial valleys, areas of differing high and low backscattering suggest varied sediment cover and/or carbonate encrustations. With the benefit of the above experience, we then interpreted data from the northern Red Sea, where there are fewer multibeam data available. Rounded fronts of halokinetic deformation are present in the Zabargad Fracture Zone, a broad, shallow valley crossing the Red Sea obliquely. The presence of halokinetic deformation here is evidence that subsidence has occurred along the fracture zone. Elsewhere in the northern Red Sea, the GLORIA data reveal folds in the evaporite surface, suggesting local areas of convergence, like those implied by multibeam data from inter-trough zones further south. Some linear features are observed, many of which are likely to be ridges overlying salt walls. Interestingly, several

Highlights • Features in GLORIA images match those in multibeam sonar data. • Salt walls suggested by lineaments in northern Red Sea. Abstract The Red Sea is an unusual example of a rift basin that transitioned from its evaporitic stage to fully open-ocean conditions at the end of the Miocene (∼5.3 Ma), much more recently than older Mesozoic margins around the Atlantic and Gulf of Mexico. The patterns of halokinetic deformation occurring in the Red Sea are potentially of interest for understanding more generally how evaporite deposits deform during this early stage. Relevant to this issue, a line of reconnaissance sidescan sonar data (GLORIA) collected along the Red Sea in 1979 is re-evaluated here. We first interpret the data with the aid of newly compiled bathymetry from multibeam sonars in the central and southern Red Sea. Features in the acoustic backscatter data are associated with ridges, valleys and rounded flow fronts produced by halokinetic deformation. Some areas of higher acoustic backscattering from the evaporites are suggested to relate to roughness produced by deformation of the evaporite surface. Within the volcanic (oceanic) axial valleys, areas of differing high and low backscattering suggest varied sediment cover and/or carbonate encrustations. With the benefit of the above experience, we then interpreted data from the northern Red Sea, where there are fewer multibeam data available. Rounded fronts of halokinetic deformation are present in the Zabargad Fracture Zone, a broad, shallow valley crossing the Red Sea obliquely. The presence of halokinetic deformation here is evidence that subsidence has occurred along the fracture zone. Elsewhere in the northern Red Sea, the GLORIA data reveal folds in the evaporite surface, suggesting local areas of convergence, like those implied by multibeam data from inter-trough zones further south. Some linear features are observed, many of which are likely to be ridges overlying salt walls. Interestingly, several

Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Marine Geophysical Research 35 (2014): 1-20, doi:10.1007/s11001-013-9196-2., If equatorial sediments form characteristic deposits around the equator, they may help to resolve the amount of northwards drift of the Pacific tectonic plate. Relevant to this issue, it has been shown that 230Th has been accumulating on the equatorial seabed faster than its production from radioactive decay in the overlying water column during the Holocene (Marcantonio et al. in Paleoceanography 16:260–267, 2001). Some researchers have argued that this reflects the deposition of particles with adsorbed 230Th carried by bottom currents towards the equator (“focusing”). If correct, this effect may combine with high pelagic productivity, which is also centered on the equator, to yield a characteristic signature of high accumulation rates marking the paleoequator in older deposits. Here we evaluate potential evidence that such an equatorial feature existed in the geological past. Seismic reflection data from seven meridional transects suggest that a band of equatorially enhanced accumulation of restricted latitude was variably developed, both spatially and temporally. It is absent in the interval 14.25–20.1 Ma but is well developed for the interval 8.55–14.25 Ma. We also examined eolian dust accumulation rate histories generated from scientific drilling data. A dust accumulation rate anomaly near the modern equator, which is not obviously related to the inter-tropical convergence zone, is interpreted as caused by focusing. Accumulation rates of Ba and P2O5 (proxies of export production) reveal a static equatorial signature, which suggests that the movement of the Pacific plate over the period 10–25 Ma was modest. The general transition from missing to well-developed focusing signatures around 14.25 Ma in the seismic data coincides with the mid-Miocene development of the western boundary current off New Zealand. This current supplies the Pacific with deep water from Antarctica, and could therefore imply a potential paleoceanographic or paleoclimatic origin. At 10.05–14., This research was supported by NERC grants NE/C508985/2, NE/I017895/1 and NE/J005282/1, and by the University of Manchester. Data acquisition was also supported by NSF grant OCE-9634141 to Lyle., 2014-09-21

If equatorial sediments form characteristic deposits around the equator, they may help to resolve the amount of northwards drift of the Pacific tectonic plate. Relevant to this issue, it has been shown that 230Th has been accumulating on the equatorial seabed faster than its production from radioactive decay in the overlying water column during the Holocene (Marcantonio et al. in Paleoceanography 16:260–267, 2001). Some researchers have argued that this reflects the deposition of particles with adsorbed 230Th carried by bottom currents towards the equator (“focusing”). If correct, this effect may combine with high pelagic productivity, which is also centered on the equator, to yield a characteristic signature of high accumulation rates marking the paleoequator in older deposits. Here we evaluate potential evidence that such an equatorial feature existed in the geological past. Seismic reflection data from seven meridional transects suggest that a band of equatorially enhanced accumulation of restricted latitude was variably developed, both spatially and temporally. It is absent in the interval 14.25–20.1 Ma but is well developed for the interval 8.55–14.25 Ma. We also examined eolian dust accumulation rate histories generated from scientific drilling data. A dust accumulation rate anomaly near the modern equator, which is not obviously related to the inter-tropical convergence zone, is interpreted as caused by focusing. Accumulation rates of Ba and P2O5 (proxies of export production) reveal a static equatorial signature, which suggests that the movement of the Pacific plate over the period 10–25 Ma was modest. The general transition from missing to well-developed focusing signatures around 14.25 Ma in the seismic data coincides with the mid-Miocene development of the western boundary current off New Zealand. This current supplies the Pacific with deep water from Antarctica, and could therefore imply a potential paleoceanographic or paleoclimatic origin. At 10.05–14.

Shallow broad elongated sediment depressions and ridges are revealed in multibeam echo-sounder data collected over the carbonate ooze in the central equatorial Pacific. These features, otherwise called “furrows”, have orientations that appear locally distorted by seabed topography as expected of contour-trending currents but at regional scale typically cross contours at high angles. In places, complex patterns suggest that formative currents have a strong time-varying component. From direction indicators, the movement of bottom waters is north to south on average, though with some movement locally south to north. There is a modest 18° average change in orientation crossing from north to south of the equator, with features to the south oriented clockwise of those to the north. This is as expected for a partly developed bottom Ekman layer, with currents in the layer deflected by the Coriolis effect with opposing senses either side of the equator. The features are less prominent on and immediately south of the equator. We evaluated these observations along with reported 230Th accumulation rates in sediment cores, which are curiously enhanced along the equator, an observation that has been previously interpreted as suggesting transport of 230Th bound to particles to the equator. Limited current meter and other data and physical oceanographic models help to explain these observations. Data from current meters 1° north of the equator show a highly asymmetric mesoscale eddy motion here, aligned with the furrows. Phase relationships between near-bed and upper ocean currents suggest an indirect coupling of upper-ocean eddies with the lower ocean. The bottom Ekman layer is predicted theoretically to thicken towards the equator. The resulting reduced bed shear stress may explain the 230Th deposition and more weakly developed furrows at the equator. Given evidence that equatorial accumulation rates of 230Th and extraterrestrial 3He both fluctuated over the Late Pleistocene, we

Since sea level stabilized 7000 yr bp, shelf seas experiencing semi-diurnal tides will have been affected by streaming four times per day. If tidal erosion of bedrock were even only marginally efficient, the ~10 million streamings since then should have left geomorphological imprints. We examine high-resolution multibeam sonar data from three areas with extreme tidal currents. The Minas Passage (Bay of Fundy) experiencing 8-knot surface tidal currents was surveyed in 2007 with a multibeam sonar. In an area near to transverse dunes, which are evidence for bedload transport, the data show local overhanging surfaces near to the sediment-rock contact, potentially created by abrasion by saltating particles. However, they are uncommon. In the Straits of Messina, where surface currents reach 10 knots, surveying revealed ridges lying oblique to the flow that are not obviously broken into separate outcrops by erosion. In the Bristol Channel, UK, sonar data collected where currents reach 3·4 knots at 1·5 m above the bed reveal outcrops of limestone with superimposed sand dunes, but only minor rounding of blocks. Holocene tidal currents have apparently been generally ineffective at eroding bedrock. We examine this issue further by compiling extreme tidal streams around the UK and from them estimate shear stresses, representing a macro-tidal environment where peak surface currents reach 9·7 knots. Those data are compared with shear stresses in mountainous rivers where long-term rates of erosion are comparable with tectonic uplift rates and are thus geomorphologically significant. Whereas river stresses reach 102–103 Pa, the largest tidal stresses are generally 101 and only rarely approach 102 Pa, too small for quarrying to operate generally. However, the vertical faces in the Minas Passage may represent the onset of abrasion. Given this limited evidence for abrasion, we explore conditions in the geological past for tides that may have locally eroded bedrock

Five quantitatively distinct gully types are identified on the Antarctic continental margin from swath bathymetric data of over 1100 individual features. The gullies differ in terms of length, width, depth, width/depth ratio, cross-sectional shape, branching order, sinuosity and spatial density. Quantitative analysis suggests that Antarctic gully morphology varies with local slope character (i.e. slope geometry, gradient), regional factors (i.e. location of cross-shelf troughs, trough mouth fans, subglacial meltwater production rates, drainage basin size), sediment yield and ice-sheet history. In keeping with interpretations of previous researchers, most gullies are probably formed by hyperpycnal flows of sediment-laden subglacial meltwater released from beneath ice-sheets grounded at the continental shelf edge during glacial maxima. The limited down-slope extent of gullies on the western Antarctic Peninsula is explained by the steep gradient and slope geometry at the mouth of Marguerite Trough, which cause flows to accelerate and entrain seawater more quickly, resulting in a reduction of the negative buoyancy effect of the sediment load. Due to pressure gradients at the ice-sheet bed caused by variations in ice thickness inside and outside palaeo-ice stream troughs, subglacial meltwater flow was generally focussed towards trough margins. This has resulted in gullies with larger cross-sectional areas and higher sinuosities at the trough margins. A unique style of gullying is observed off one part of the western Antarctic Peninsula, corresponding to an area in which the ice-sheet grounding line is not thought to have reached the shelf edge during the Last Glacial Maximum. We interpret the features in this area as the cumulative result of slope processes that operated over a long period of time in the absence of hyperpycnal meltwater flows.

The growth and decay of oceanic hotspot volcanoes are intrinsically related to a competition between volcanic construction and erosive destruction, and coastlines are at the forefront of such confrontation. In this paper, we review the several mechanisms that interact and contribute to the development of coastlines on oceanic island volcanoes, and how these processes evolve throughout the islands' lifetime. Volcanic constructional processes dominate during the emergent island and subaerial shield-building stages. During the emergent island stage, surtseyan activity prevails and hydroclastic and pyroclastic structures form; these structures are generally ephemeral because they can be rapidly obliterated by marine erosion. With the onset of the subaerial shield-building stage, coastal evolution is essentially characterized by rapid but intermittent lateral growth through the formation of lava deltas, largely expanding the coastlines until they, typically, reach their maximum extension. With the post-shield quiescence in volcanic activity, destructive processes gradually take over and coastlines retreat, adopting a more prominent profile; mass wasting and marine and fluvial erosion reshape the landscape and, if conditions are favorable, biogenic processes assume a prominent role. Post-erosional volcanic activity may temporarily reverse the balance by renewing coastline expansion, but islands inexorably enter in a long battle for survival above sea level. Reef growth and/or uplift may also prolong the island's lifetime above the waves. The ultimate fate of most islands, however, is to be drowned through subsidence and/or truncation by marine erosion.

Using a mixed-method design, my dissertation examines three interrelated puzzles of state violence during counterinsurgency campaigns. First, why does state repressive violence effectively thwart rebellion is some cases while escalating it in others? Using simultaneous equation modeling on 139 cases, I find that collective (or indiscriminate) state violence is associated with a long-lasting backlash effect against the government, while selective (i.e., individual-level) state targeting is expected to deter rebellion effectively. The second puzzle is why are states so seldom selective and so frequently collective in their use of violence? I argue that the scope of state violence is in, in part, a function of the capacities of the state agencies in the security sector tasked with counterinsurgency. State agents with high coercive capacity (e.g., national militaries) tend to lack sufficient local sources to identify and target insurgents at the individual level. Most local security organizations (e.g., police) that would otherwise have access to local intelligence lack the organizational competence to exploit this knowledge and become an efficient counterinsurgency force. The result is to rely on information about collectives (locations, ethnic groups, etc.) and target accordingly, which is associated with an escalation of the threat. This argument is supported by the first two stages of the Punjab crisis in India, where initial police attempts at thwarting rising extremism were incompetent and the armys heavy-handed approach produced a backlash against the government. Selective targeting requires local intelligence capacity and competent organizational capacity. The third puzzle is how do states (or state agents) effectively overcome these obstacles to carry out selective targeting? Using qualitative process tracing supplemented by elite interviews in India, I explain how the Punjab Police built organizational and intelligence capacity over the ensuing years to identi

Shallow broad elongated sediment depressions and ridges are revealed in multibeam echo-sounder data collected over the carbonate ooze in the central equatorial Pacific. These features, otherwise called “furrows”, have orientations that appear locally distorted by seabed topography as expected of contour-trending currents but at regional scale typically cross contours at high angles. In places, complex patterns suggest that formative currents have a strong time-varying component. From direction indicators, the movement of bottom waters is north to south on average, though with some movement locally south to north. There is a modest 18° average change in orientation crossing from north to south of the equator, with features to the south oriented clockwise of those to the north. This is as expected for a partly developed bottom Ekman layer, with currents in the layer deflected by the Coriolis effect with opposing senses either side of the equator. The features are less prominent on and immediately south of the equator. We evaluated these observations along with reported 230Th accumulation rates in sediment cores, which are curiously enhanced along the equator, an observation that has been previously interpreted as suggesting transport of 230Th bound to particles to the equator. Limited current meter and other data and physical oceanographic models help to explain these observations. Data from current meters 1° north of the equator show a highly asymmetric mesoscale eddy motion here, aligned with the furrows. Phase relationships between near-bed and upper ocean currents suggest an indirect coupling of upper-ocean eddies with the lower ocean. The bottom Ekman layer is predicted theoretically to thicken towards the equator. The resulting reduced bed shear stress may explain the 230Th deposition and more weakly developed furrows at the equator. Given evidence that equatorial accumulation rates of 230Th and extraterrestrial 3He both fluctuated over the Late Pleistocene, we

Since sea level stabilized 7000 yr bp, shelf seas experiencing semi-diurnal tides will have been affected by streaming four times per day. If tidal erosion of bedrock were even only marginally efficient, the ~10 million streamings since then should have left geomorphological imprints. We examine high-resolution multibeam sonar data from three areas with extreme tidal currents. The Minas Passage (Bay of Fundy) experiencing 8-knot surface tidal currents was surveyed in 2007 with a multibeam sonar. In an area near to transverse dunes, which are evidence for bedload transport, the data show local overhanging surfaces near to the sediment-rock contact, potentially created by abrasion by saltating particles. However, they are uncommon. In the Straits of Messina, where surface currents reach 10 knots, surveying revealed ridges lying oblique to the flow that are not obviously broken into separate outcrops by erosion. In the Bristol Channel, UK, sonar data collected where currents reach 3·4 knots at 1·5 m above the bed reveal outcrops of limestone with superimposed sand dunes, but only minor rounding of blocks. Holocene tidal currents have apparently been generally ineffective at eroding bedrock. We examine this issue further by compiling extreme tidal streams around the UK and from them estimate shear stresses, representing a macro-tidal environment where peak surface currents reach 9·7 knots. Those data are compared with shear stresses in mountainous rivers where long-term rates of erosion are comparable with tectonic uplift rates and are thus geomorphologically significant. Whereas river stresses reach 102–103 Pa, the largest tidal stresses are generally 101 and only rarely approach 102 Pa, too small for quarrying to operate generally. However, the vertical faces in the Minas Passage may represent the onset of abrasion. Given this limited evidence for abrasion, we explore conditions in the geological past for tides that may have locally eroded bedrock