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Imaging and inversion with seismic data recorded with sources and receivers at the surface are powerful tools to infer knowledge about the subsurface. However, creating an image with seismic data is unfortunately not as easy as taking a picture with a smartphone. The estimated subsurface models in many situations are far from ideal due to the low quality nature of the data. One of the reasons can be weathering of the near-surface geology that generates unconsolidated material characterized by slow velocity with rapidly varying, heterogeneous and season-dependent nature. Acquiring seismic data on such near-surface leads to complex wave propagation, posing challenges to imaging and inversion. In this dissertation, we tackle the weathering effects during seismic data processing, imaging and inversion with low-rank-based methods. One approach to tackle the weathering effects on seismic data is removing them during seismic data processing. To do so for 2D data, we propose a model-independent low-rank-based near-surface estimation and correction in the midpoint-offset-frequency domain. In this domain, ideal data exhibit low rank structures, which get destroyed due to the influence of the weathering layers. Accordingly, the method makes use of the redundant nature of seismic data that allows for accurate approximation by low-rank matrices. To estimate the time shifts that compensate for the weathering effects, we cross-correlate a data set influenced by the near-surface weathering layers with its low-rank approximated version. Since we estimate time shifts (commonly referred to as statics) and no longer the directly low-rank approximated data, we avoid losses of the amplitude information. To improve the estimated statics and to alleviate the need for accurate rank selection for low-rank approximation, we implement the method in an iterative and multi-scale fashion. Since the low-rank approximation deteriorates at high frequencies, we utilize its better performance, ImPhys/Medical Imaging, ImPhys/Verschuur group

Municipal solid waste incineration (MSWI) bottom ash, due to its high mineral content, presents great potential as supplementary cementitious material (SCM). Weathering, also known as aging, is a treatment process commonly employed in waste management to minimize the risk of heavy metal leaching from MSWI bottom ash. Using weathered MSWI bottom ash to produce blended cement pastes is considered as a high-value-added and sustainable waste disposal solution. However, a critical challenge arises from the metallic aluminum (Al) in weathered MSWI bottom ash, which is known to induce detrimental effects such as volume expansion and strength loss of blended cement pastes. While most metallic Al in weathered MSWI bottom ash can be removed with eddy current separators in metal recovery plants, the residual metallic Al, owing to its small particle size, cannot be removed with the same technique. This study is dedicated to addressing this issue. An in-depth analysis was conducted on residual metallic Al embedded in weathered MSWI bottom ash particles, aiming to guide the removal of this metal. This analysis revealed that mechanical removal was the most suitable method for extracting metallic Al. The specific processes and mechanisms underlying this method were elucidated. After reducing metallic Al content in weathered MSWI bottom ash by 77 %, a significant improvement in the quality of blended cement pastes was observed. This work contributes to the broader adoption of mechanical treatments for removing residual metallic Al from weathered MSWI bottom ash and facilitates the application of treated ash as SCM., Materials and Environment

Ectomycorrhizal fungi contribute to weathering and may be used as an alternative to fertilizers. Their usefulness is dependent on how much they can contribute to the weathering that takes place in the same area. This review discusses the current literature on how much ectomycorrhizal fungi contribute to the total chemical weathering rate. There are few studies that document said contribution, with most geomycological weathering studies only reporting weathering numbers for the fungi. The weathering contribution towards apatite and olivine appears to be higher (at 28% and 16% respectively) than the 0.2% and 0.5% attributed to feldspar and 2% attributed to biotite. More research is needed to understand how much fungi can contribute to weathering. It would be preferable to study multiple species of both minerals and fungi at once in the same drainage area.

Microplastics (MPs) are ubiquitous pollutants of increasing concern in aquatic systems. However, little is still known about the impacts of weathered MPs on plankton at the community level after long-term exposure. In this study, we investigated the effects of weathered MPs on the structure and dynamics of a Baltic Sea planktonic community during ca. 5 weeks of exposure using a mesocosm approach (2 m3) mimicking natural conditions. MPs were obtained from micronized commercial materials of polyvinyl chloride, polypropylene, polystyrene, and polyamide (nylon) previously weathered by thermal ageing and sunlight exposure. The planktonic community was exposed to 2 Όg L-1 and 2 mg L-1 of MPs corresponding to measured particle concentrations (10–120 Όm) of 680 MPs L-1 and 680 MPs mL-1, respectively. The abundance and composition of all size classes and groups of plankton and chlorophyll concentrations were periodically analyzed throughout the experiment. The population dynamics of the studied groups showed some variations between treatments, with negative and positive effects of MPs exhibited depending on the group and exposure time. The abundance of heterotrophic bacteria, pico- and nanophytoplankton, cryptophytes, and ciliates was lower in the treatment with the higher MP concentration than in the control at the last weeks of the exposure. The chlorophyll concentration and the abundances of heterotrophic nanoflagellates, Astromoeba, dinoflagellate, diatom, and metazooplankton were not negatively affected by the exposure to MPs and, in some cases, some groups showed even higher abundances in the MP treatments. Despite these tendencies, statistical analyses indicate that in most cases there were no statistically significant differences between treatments over the exposure period, even at very high exposure concentrations. Our results show that weathered MPs of the studied conventional plastic materials have minimal or negligible impact on planktonic communities after l

Identifying wood species of each wood element of a historical wooden building and investigating the changes in wood properties due to exposed outdoors during its service life are important prerequisites for the maintenance and renovation of historical wooden buildings. In the present study, the changes in wood properties occurring during natural aging of two facade elements taken from a traditional house, which has a service life of approximately 100 years, were investigated. Destructive tests were used for the experiments. The wood species, moisture content, wood density, water absorption rate and chemical structure of both facade elements were determined. Microscopic analysis revealed that the molding was made from the wood of Scots pine (Pinus sylvestris) and the window jamb was made from chestnut (Castanea sativa). It was found that the cellulose and lignin on the outer surface of aged woods of both facade elements were degraded according to the FTIR analysis. The moisture and density values of aged wood for both facade elements were smaller than those of recent wood. The water absorption rates of aged woods of both molding and window jamb increased with natural aging, La identificación de las especies de madera de cada elemento de madera de un edificio histórico de madera y la investigación de los cambios en las propiedades de la madera debido a la exposición al aire libre durante su vida útil son requisitos previos importantes para el mantenimiento y la renovación de edificios históricos de madera. En el presente estudio se investigaron los cambios en las propiedades de la madera que ocurren durante el envejecimiento natural de dos elementos de fachada tomados de una casa tradicional, que tiene una vida útil de aproximadamente 100 años. Para los experimentos se utilizaron pruebas destructivas. Se determinaron las especies de madera, el contenido de humedad, la densidad de la madera, la tasa de absorción de agua y la estructura química de ambos elementos de la fachada. El análisis microscópico reveló que la moldura estaba hecha de madera de pino silvestre ( Pinus sylvestris ) y la jamba de la ventana estaba hecha de castaño (Castanea sativa ). Se encontró que la celulosa y la lignina en la superficie exterior de las maderas envejecidas de ambos elementos de la fachada se degradaron según el análisis FTIR. Los valores de humedad y densidad de la madera envejecida para ambos elementos de fachada fueron menores que los de la madera reciente. Las tasas de absorción de agua de las maderas envejecidas tanto de molduras como de jambas de ventanas aumentaron con el envejecimiento natural.

Deep atmospheric convection in the Indo-Pacific Warm Pool (IPWP) represents a major source of heat and moisture, thereby affecting the global climate, but its past changes remain debated. Here, we present sub-millennial clay mineralogy and elemental records spanning the last 40 kyr from within the IPWP. From these data, we infer millennial-scale fluctuations in precipitation, with generally lower precipitation during Heinrich Stadials 1-4, corresponding to El Niño-like conditions. Higher precipitation coincided with the warm interstadials, accompanied by La Niña-like conditions. Moreover, our record indicates the lowest precipitation occurred during the late Holocene, supporting the hypothesis of a stronger-than-modern Walker circulation during the Last Glacial Maximum. In combination with other proxy records and TraCE-21 modelling results, we recognize a distinct spatial heterogeneity of precipitation within the IPWP, resulting from the dominant influences of the ENSO-like system and migration of the Intertropical Convergence Zone in the eastern and western IPWP, respectively. Key Points We present sub-millennial clay mineral and elemental records from the Indo-Pacific Warm Pool spanning the last 40 kyr Our records indicate higher precipitation during La Niña-like conditions and lower precipitation during El Niño-like conditions Different patterns and controls on precipitation variability between the eastern and western Indo-Pacific regions are revealed Plain Language Summary Tropical rainfall systems in the Indo-Pacific Warm Pool (IPWP) play a significant role in transferring energy and moisture. However, their millennial-scale variabilities in precipitation during remains poorly understood. Here, we provide sub-millennial sediment mineralogy and elemental reconstructions spanning the last 40,000 years from a sediment core in the IPWP. We infer that variability in precipitation induced by atmospheric convection in the IPWP is the main factor controlling the variab

The risks of crude oil spills occurring within the Arctic heighten as ongoing impacts of climate change have given rise to ever increasing amounts of ship traffic. The Baffin Island Oil Spill (BIOS) project was designed in 1979 to further the collective understanding regarding the fate and behaviour of crude oil within the Arctic marine environment. A series of experimentally controlled oil releases occurred in Cape Hatt, Baffin Island, NU between 1980-1982 and were left subject to natural weathering processes. The sites of the BIOS project were revisited on numerous occasions to observe the long-term fate of crude oil spilled in an otherwise pristine, remote Arctic setting; most recently during the 2019 CCGS Amundsen expedition. Bulk surface (0-2cm) and subsurface (5-10cm) sediment samples were collected from oiled backshore plots from Crude Oil Point and Bay 106 within the Z-lagoon, and from the intertidal sediments of Bay 11 within the Ragged Channel, where a surface oil slick was left to encroach onto the beach. Collected samples were analyzed for a total of 99 petroleum hydrocarbons including Polycyclic Aromatic Hydrocarbons (PAHs), n-alkanes, branched alkanes, alkylcycloalkanes, hopane and sterane biomarkers, and alkylbenzenes using Gas Chromatography Mass Spectrometry. These hydrocarbon groups were detected in concentrations ranging from 0.0486 – 14.0, 1.15 - 1170, 0.224 – 51.7, 0.0643 – 16.9, 0.213 – 11.7, and 0.0171 – 8.60 mg/kg, respectively. The oiled sediments were generally observed to contain the highest concentrations of each hydrocarbon group at Crude Oil Point, followed by Bay 106, then finally Bay 11; suggesting that tidal and wave action were significant contributors to the removal of petroleum. Fourteen of the 16 US EPA priority PAHs were detected in concentrations exceeding the marine sediment quality guideline limits established by the Canadian Council of Ministers of the Environment, individually ranging from 7.00 – 640 ug/kg. The Toxic Equiva

The Intex laterite deposit in Mindoro, Philippines is derived from the weathering of the ultramafic rocks under a tropical climate. This study investigates the several types of serpentines and the effect of the degree of chemical weathering of ultramafic rocks and laterites on the enrichment of Ni in the deposit. The five types of serpentines are differentiated based on their textural features and Raman spectral data. Type I, type II, type III, and type IV serpentines contain a low amount of NiO (average 0.15 wt%), and their formation is linked to the previous exhumation of the ultramafic body. Conversely, type V serpentines show the highest NiO contents (average 1.42 wt%) and have the composition of serpentine-like garnierites, indicating a supergene origin. In the limonite horizon, goethite is the main ore mineral and shows high NiO contents of up to 1.68 wt%, whereas the Mn-oxyhydroxides (i.e., asbolane and lithiophorite-asbolane intermediate) display substantial amounts of CoO (up to 11.3 wt%) and NiO (up to 15.6 wt%). The Ultramafic Index of Alteration (UMIA) and Index of Lateritization (IOL) are used to characterize the different stages of weathering of rocks and laterites. The calculated index values correspond to a less advanced stage of weathering of the Intex laterites compared with the Berong laterites. The Berong deposit is a Ni-Co laterite deposit in the Philippines, which is formed from the weathering of the serpentinized peridotite. The less extreme degree of weathering of the Intex laterites indicates less advanced leaching, and thereby the re-distribution of Ni, Si, and Mg from the limonite towards the saprolite horizon may have resulted in the poor precipitation of talc-like (kerolite-pimelite) and sepiolite-like (sepiolite-falcondoite) phases in the studied saprolite horizon. Nickel in the Intex deposit has undergone supergene enrichment similar to other humid tropical laterite deposits.

This thesis project revolves around the last days of an abandoned building in decay, facing demolition. It is situated in Värtahamnen, a harbor area in Stockholm. The area is the subject of a major urban planning project in the upcoming decade. In my project my aim is to contemplate this condition of of a building and how to approach and use the ephemerality of architecture and design in the creative process. By extracting different material behaviors caused by decay and exploring them experimentally, a diverse “buffet” of design concepts and methods are presented. The project also orbits around the subject of preservation, a topic commonly debated during interventions in the built heritage. Instead of taking a stand for or against the demolition of the building, the field of experimental preservation is used as a theoretical and methodological background in the design process, as a way to expand the scope on how to navigate and work artistically with preservation. In conclusion, this project tries to revise our perspective on the concept of decay as something destructive and instead suggest the creative potential in understanding it. It also contributes with reflections and speculations on how we can find new creative strategies for taking the whole lifespan of a design project into account already from the beginning.

Bioplastics that possess characteristics like durability and low cost are desired for versatile applications in industries such as automotive manufacturing, marine transport manufacturing, aerospace applications, and the building industry. The automotive industry is an example of an industry that is now shifting towards a more focused approach addressing the issue concerning sustainability and the development of sustainable material. To achieve a lightweight and sustainable construction, one of the methods used by the automotive original equipment manufacturers is by substituting conventional fossil-based, non-renewable composites, and metallic materials with a bio-based alternative. One of the drawbacks with biobased polymers can be the poor interfacial adhesion, leading to poor mechanical properties when compares to conventional material. The aim of this research is to investigate if a low-cost by-product could be used as a component in a composite matrix material in the automotive industry to reduce the final weight and increase the non-petrochemical material usage of composite material without compromising the thermal and mechanicals properties demanded. In this research, lignin was chemically altered by esterification the functional groups to increase the compatibility with polylactic acid. The esterification was performed with the use of acetic acid anhydride and pyridine. To evaluate and determine the esterification, Fourier transform Infrared Spectroscopy was used. By blending the modified lignin with polylactic acid the intention was to improve the thermomechanical properties and the interfacial linkage between the components. The effects of lignin acetylation on the tensile properties, impact strength, and thermal stability and moisture repellence behaviour were investigated. According to the experimental results the modification of lignin, increased the impact strength for all the blends containing acetylated lignin compares to pristine lignin. The larges

A rising sea level threatens historic buildings and towns that tie together the collective identity of a community, but because the disaster is often prolonged and the loss occurs all around us, the current model for memorials will not accommodate the grief the future holds. Memorials are meant to aid in remembering and often point to a specific event or place where a historic event happened. If the loss is ongoing and happening everywhere, the memorial will need to adapt and address more universal concepts to be inclusive. A memorial can no longer simply point to a moment in the past. They must help educate about important issues and experiences that impact daily life. Future memorials need to address diverse narratives and complex histories to remain relevant when cultural values shift. There is an architectural opportunity to reflect on more universal experiences that are on-going and affect everyone, but these memorials need to operate at a local level to make big issues, like climate change, more digestible. By focusing on one symptom, like sea level rise, and using a specific instance of loss as the backdrop, visitors can experience the profound impact of climate change firsthand. The Historic Point Lookout Lighthouse will become the site for a new theoretical tidal park and climate change memorial. It will memorialize what has been lost to rising sea levels and heighten visitors' awareness of their own relationships to water. The design will present the dynamics of water in the short term, mid term, and long term to make the subtle changes of rising sea levels evident. The site will transform over the course of the day with tidal action, over the years with material weathering, and over the decades with sea level rise. Locals will have a place to return to as the surrounding area is swallowed by the bay and they are forced to relocate. The building itself will act as a metaphorical anchor and storytelling device, marking the place that experienced a historica

En aquest treball s'investiga la fragmentació de blocs en despreniments rocosos, procés que influeix significativament en el risc d'aquest tipus de moviments de vessant, però que encara és poc conegut. Es parteix de dos *TFE previs sobre aquest tema. L'objectiu d'aquest treball és analitzar les condicions d'inici de la fragmentació; més concretament: 1) determinar si existeixen llindars d'energia cinètica, força normal o de pressió normal, i 2) analitzar si dits possibles llindars depenen de la geometria de l'impacte (cara, aresta, vèrtex)., En este trabajo se investiga la fragmentación de bloques en desprendimientos rocosos, proceso que influye significativamente en el riesgo de este tipo de movimientos de ladera, pero que aún es poco conocido. Se parte de dos TFE previos sobre este tema. El objetivo de este trabajo es analizar las condiciones de inicio de la fragmentación; más concretamente: 1) determinar si existen umbrales de energía cinética, fuerza normal o de presión normal, y 2) analizar si dichos posibles umbrales dependen de la geometría del impacto (cara, arista, vértice)., This paper investigates the fragmentation of blocks in rockfalls, a process that significantly influences the risk of this type of landslides, but which is still poorly understood. It starts from two previous TFE on this subject. The objective of this work is to analyze the fragmentation initiation conditions; more specifically: 1) determine if there are kinetic energy, normal force or normal pressure thresholds, and 2) analyze if said possible thresholds depend on the geometry of the impact (face, edge, vertex).

Microplastics are an emerging and persistent pollutant due to their threat to global ecological systems and human health. Recent studies showed that microplastics have infiltrated the remote Third Pole - the Tibetan Plateau. Here, we summarize the current evidence for microplastic pollution in the different environments (rivers/lakes, sediment, soil, ice/snow and atmosphere) of the Tibetan Plateau. We assess the spatial distribution, source, fate, and potential ecological effects of microplastics in this broad plateau. The integrated results show that microplastics were pervasive in biotic and abiotic components of the Tibetan Plateau, even at the global highest-altitude, Mt. Everest. Although the concentration of microplastics in the Tibetan Plateau was far below that found in the densely populated lowlands, it showed a higher concentration than that in the ocean system. Tourist populations are identified as a substantial source of anthropogenic plastic input rather than local residents due to the rapid development of the tourism industry. In the sparsely inhabited remote area of the Tibetan Plateau, long-range atmospheric transport facilitates allochthonous microplastic diffusion. Robust solar radiation in the Tibetan Plateau might enhanced production of secondary microplastics by weathering (UV-photooxidation) of abandoned plastic waste. A rough estimation showed that the microplastic export flux from melting glaciers was higher than that measured in most of the world's largest rivers, which affects local and downstream areas. Since the Tibetan Plateau is vital for Asian water supply and numerous endangered wildlife, the potential human and ecological risk of microplastics to these fragile ecosystems needs to be fully evaluated within the context of climate-change impacts.

Primary minerals that enter soils through bedrock weathering and atmospheric deposition can generate poorly crystalline minerals (PCM) that preferentially associate with soil organic carbon (SOC). These associations hinder microbial decomposition and the release of CO2 from soils to the atmosphere, making them a critical geochemical control on terrestrial carbon abundance and persistence. Studies that explore these relationships are typically derived from soil chronosequences that experience negligible erosion and thus do not readily translate to eroding landscapes. Here, we propose a theoretical framework to estimate steady-state PCM density and stocks for hilly and mountainous settings by coupling geochemical and geomorphic mass balance equations that account for soil production from bedrock and dust, soil erosion, PCM formation from weathering, and the transformation of PCMs into crystalline phases. We calculate an optimal erosion rate for maximum PCM abundance that arises because PCMs are limited by insufficient weathering at faster erosion rates and loss via “ripening” into more crystalline forms at slower erosion rates. The optimal erosion rate for modeled hilltop soil is modulated by reaction rate constants that govern the efficiency of primary mineral weathering and PCM ripening. By comparing our analysis with global compilations of erosion and soil production rates derived from cosmogenic nuclides, we show that landscapes with slow-to-moderate erosion rates may be optimal for harboring abundant PCM stocks that can facilitate SOC sequestration and limit turnover. Given the growing array of erosion-topography metrics and the widespread availability of high-resolution topographic data, our framework demonstrates how weathering and critical zone processes can be coupled to inform landscape prioritization for persistent SOC storage potential across a broad range of spatial and temporal scales.

Vegetation plays a key role in the hydrological and biogeochemical cycles. It can influence soil water fluxes and transport, which are critical for chemical weathering and soil development. In this study, we investigated soil water balance and solute fluxes in two soil profiles with different vegetation types (cushion-forming plants vs. tussock grasses) in the high Ecuadorian Andes by measuring soil water content, flux, and solute concentrations and by modeling soil hydrology. We also analyzed the role of soil water balance in soil chemical weathering. The influence of vegetation on soil water balance and solute fluxes is restricted to the A horizon. Evapotranspiration is 1.7 times higher and deep drainage 3 times lower under cushion-forming plants than under tussock grass. Likewise, cushions transmit about 2-fold less water from the A to lower horizons. This is attributed to the higher soil water retention and saturated hydraulic conductivity associated with a shallower and coarser root system. Under cushion-forming plants, dissolved organic carbon (DOC) and metals (Al, Fe) are mobilized in the A horizon. Solute fluxes that can be related to plant nutrient uptake (Mg, Ca, K) decline with depth, as expected from biocycling of plant nutrients. Dissolved silica and bicarbonate are minimally influenced by vegetation and represent the largest contributions of solute fluxes. Soil chemical weathering is higher and constant with depth below tussock grasses but lower and declining with depth under cushion-forming plants. This difference in soil weathering is attributed mainly to the water fluxes. Our findings reveal that vegetation can modify soil properties in the uppermost horizon, altering the water balance, solute fluxes, and chemical weathering throughout the soil profile.

This interdisciplinary dialogue draws on climatology and cultural studies to explore the phenomenon of “Saharan dust” that passes through and beyond the Spanish Mediterranean Basin. The dialogic process seeks to unearth the power relations within which weather stories and the authors are always already entangled, with a view to re-imagining weather writing and climatic storytelling in decolonial terms. Our parallel inquiries trace how origin stories, material mobilities, atmospheres, and environmental regulation work to codify the aeolian dust as an intrusion across borders. Drawing on critical theory, we argue that this weather “from” the Sahara Desert is othered in Eurocentric weather narratives, mapping onto geopolitical logic of “Fortress Europe”. Our research is instructed by postcolonial thought, political ecology, and the speculative feminist position of weathering. Through critical engagement with science in context, we dwell lastly on African air quality and experiences of weathering atmospheric dust further upwind. Our concluding comments speculatively drift with Mediterranean winds to animate a positionality of middleness.

By analyzing the texture, composition and chemical composition of loess soils, the reconstruction ofpast climate regimes is enabled, which can improve our understanding of current and future climatechange. Properties such as grain size and composition, mineralogy, organic matter and chemicalcomposition can provide information about which environmental factors were present during thedeposition of the sediment, which can lead to a detailed picture of the climate history of a site. Researchon loess soils in the polar regions is particularly valuable because its climate is most rapidly affected byglobal warming. The purpose of the study has therefore been to understand and convey new data to thepaleo-climate around the Arctic by examining and analyzing loess soil sequences at a depth between 0and 175 cm from Adventdalen, Svalbard. In this study, the samples are analyzed with XRF (X-rayfluorescence) and LOI (Loss of Ignition). XRF is used to find out the mineral composition of the soils,while LOI is used to find out the percentage of organic content and carbonates.Data from the oldest part of the stratigraphic section indicate a sharp increase in weathering, from acooler period about 3000 years ago to a warming until about 2000 years ago. Weathering intensitiesderived from Na/Al-based indices show relatively frequent oscillations throughout the section, but arestable from about 100-70 cm. The high and stable weathering values during this period can probably beattributed to the Medieval Warm Period, which coincides with the relative dating of the site. Datacollected from the LOI shows a clear trend throughout the section, with a decrease in organic matterfrom 3000 BC to the present.

Los desprendimientos rocosos sobre carreteras son un peligro que debe estudiarse y parametrizarse bien para identificar las zonas más sensibles de las infraestructuras. El objetivo de este trabajo es realizar simulaciones de desprendimientos sobre carreteras que consideren la fragmentación de los bloques. Posteriormente se analizan los resultados y se contrastan con las simulaciones que no consideran la fragmentación. El objetivo final es obtener la tramificación de la carretera en función de la peligrosidad., Rockslides on roads are a hazard that needs to be studied and parameterised in order to identify the most sensitive areas of the infrastructure. The aim of this work is to carry out simulations of landslides on roads that take into account the fragmentation of the blocks. The results are then analysed and contrasted with simulations which do not take fragmentation into account. The results are then analysed and contrasted with simulations that do not take fragmentation into account, obtaining the classification of the road according to the hazard., Els despreniments rocosos sobre carreteres són un perill que cal estudiar i parametritzar bé per identificar les zones més sensibles de les infraestructures. L'objectiu d'aquest treball és fer simulacions de despreniments sobre carreteres que considerin la fragmentació dels blocs. Posteriorment se n'analitzen els resultats i es contrasten amb les simulacions que no consideren la fragmentació. L'objectiu final és obtenir la tramificació de la carretera en funció de la perillositat.

The NSW Government is currently planning the development of a major road corridor in the Milton and Ulladulla region of southern NSW (“the Milton Ulladulla bypass”). There is a need for more information on the geology beneath the proposed road corridor, as this area has seen relatively limited geological studies conducted in the past. The work presented here aims to provide new geological data through the analysis of borehole samples collected along the proposed extent of the Milton- Ulladulla bypass. A total of 45 samples were examined. These were taken from 23 boreholes. Each core sample was cut vertically, with one side crushed and prepared for geochemical analysis through XRF, with the remaining half used as an archive copy and kept for visual analysis. XRF compositions were analysed and placed on differing plots for comparison along with maps made using ArcGIS Pro to investigate spatial trends. The results show that there is an area that has extensive alteration and is located in one zone near the boundary of the Milton Monzonite and Wandrawandian Formation. Remaining samples that demonstrate changes in structure and colour follow a pattern of being brown and crumbly which can be considered to be weathered samples that exist throughout the area. The alteration is visible within hand samples, which show degradation and loss of structure and texture. These altered samples also record geochemical data where elements with outliers are almost exclusively found within altered material. The project results have been summarised in several maps which show refined estimates of the boundaries of the geological units in the region, the ’depth to altered material’ to aid future drilling and foundation plans and regions of high sulphur (which potentially identify areas that are at higher risk of acid sulphate soils, which may impact foundation planning). Future work could build upon the results found within this study by further sampling to identify the true extent of the al

A diversity of factors, led by lithology, weathering, and erosion processes, plays a significant role in the formation and future of badland terrains. Then on previous observations it can be concluded that surface flow processes are the first trigger of erosion and that intense soil erosion combined with rapid and deep weathering are tightly connected to high erosion rates.Since climate change presents a global issue that gains increasing attention and due to the complexity of the interactions and processes that are a part of general badlands origin and evolution, a weathering experiment on badland sediments from China was conducted. Explaining temporal changes, the impact of different precipitation types and its durations of exposure on sediments during weathering processes, as well as its impact on leachate ions behaviour are the aims behind this experiment.Red clayey siltstone and mudstone badland sediments selected for the laboratory experiment were organized in four sets that included three different samples, making a total of 12 treated samples. Based on field climate data, in laboratory conditions samples were exposed to rain, acid rain, snow, and acid snow through fifteen daily cycles. Leachate was collected after each cycle and its volume, pH, electrical conductivity (EC), and ion concentrations were measured and analysed from the leachate. Changes occurring on the surface of the sample were observed through photographs taken at the end of each cycle.Based on obtained results it can be said that the main differences occur when comparing rain and snow treatments generally. Temporal, cyclic changes were, to a certain extent, noticed through sediment decay. More importantly, durations of sediment exposure to precipitation proved to be crucial for weathering processes of tested siltstones and mudstones, having exclusion and ionic forces - ion exchange chromatography as dominant chemical processes.

In the summer of 2020, locked by the confinement, we began the four-handed writing of "Intemperie: políticas de la voluntad, poéticas del cobijo" [Weathering: Politics of Will, Poetics of Shelter]. A year later that text became a call for papers that led to an international seminar with the same name held during June 2021. Now, two years later, we are pleased to publish this dossier. "Intemperie" has traveled in different formats, registers and geographies. The first impulse to write was motivated by a feeling of loss and a desire to share, from two very distant geographies, Chile and Mexico, what was happening to us during the first weeks of confinement., En el verano del 2020, encerrades por el confinamiento, comenzamos la escritura a cuatro manos de "Intemperie: políticas de la voluntad, poéticas del cobijo". Un año después ese texto se convirtió en una convocatoria que derivó en un seminario internacional con el mismo nombre llevado a cabo durante junio del 2021. Ahora, dos años más tarde, tenemos el gusto de publicar este dossier. "Intemperie" ha viajado en formatos, registros y geografías distintas. El primer impulso de la escritura fue motivado por un sentimiento de extravío y un deseo por compartir, desde dos geografías muy distantes, Chile y México, lo que nos estaba pasando durante las primeras semanas de confinamiento.

Voxels are cells on a 3D regular grid. Voxel-based scenes have many applications, including frequent use in simulations or games. Over the years, the field of high-resolution voxel scenes has progressed significantly, allowing for compressing and real-time editing of high-resolution scenes. This possibility of editing high-resolution scenes led to various editing tools. This thesis aims to expand this set of tools with a focus on more complex simulation-based solutions. We explored the field of terrain weathering and decided on a spheroidal weathering tool to perform weathering on voxel-based scenes. One of the existing limitations of this particular method was that it did not account for debris simulation. We ultimately decided to add a granular simulation using a layer-based approach that integrates with the weathering tool but is also able to function in a standalone manner. This thesis presents three highly-customizable editing tools for voxel-based scenes: spheroidal weathering, granular simulation, and a combined tool that enables weathering with debris simulation. These tools are integrated into the HashDAG framework, which is a high-resolution voxel-grid method building upon a directed acyclic graph representation of a sparse voxel octree. Our solutions enable close to real-time editing for changes with a smaller regional support. There is room for improvement in terms of performance at scale, with various potential ideas presented in the future work section., Computer Science

The aim of this work is presenting a group of glasses excavated from the archaeological site Casas del Turuñuelo (Guareña, Badajoz, Spain), whose destruction dates back to the 5th Century BCE. Different types of glasses were found, among them two thick-walled translucent bowls and a very fine blue-coloured bowl. The study and conservation of these pieces has made it possible to characterize the composition of the different types of glass and their specific degradation, and to identify the possible origin where they were manufactured, in the Eastern Mediterranean. In addition, it has managed to recover the original surface and shape of these pieces and has given them the necessary consistency to be well preserved and studied.

Cette maîtrise s’insère dans le projet Trough-Lens-Cones (TLC), qui a lieu à l’Institut Interdisciplinaire d’Innovation Technologique (3IT) en association avec Terra Firma Innovations. La particularité de ces modules vient de leur optique secondaire, qui consiste en un système optimisé TLC qui permet de focaliser la lumière solaire jusqu’à 1500 fois sur les cellules photovoltaïques, soit une irradiation extrême. Ainsi, une quantité réduite de cellules est requise pour un même rendement énergétique et le coût de production pourrait drastiquement diminuer. Des tests de vieillissement accéléré (VA) seront effectués afin de mesurer la longévité de ce système, qui devra soutenir des températures jusqu’à 140°C et une irradiation UV allant jusqu’à 2 W/cm2 . Il faudra toutefois amplifier ces conditions afin de précipiter le processus de vieillissement. Lors de cette maîtrise, l’étude des modes de défaillance du module sera réalisée. La température, l’humidité et l’impact des rayons UV sont les principaux facteurs de dégradation qui seront étudiés. L’utilisation de modèles théoriques, tels que ceux d’Arrhenius ou de Peck, permettra de savoir combien de temps le module doit être mis sous des conditions contrôlées pour simuler des vieillissements de 20 à 50 ans. D’abord, des tests avec un seul facteur de dégradation seront effectués. Ensuite, la mesure du degré de dégradation des modules permettra de valider les hypothèses basées sur les modèles théoriques. Une fois ces informations bien établies, il sera possible de mieux comprendre comment combiner les différents facteurs de dégradation. Finalement, des tests de VA en combinant ces facteurs seront effectués. L’analyse de ces tests et l’utilisation de modèles mathématiques tels que celui d’Eyring généralisé permettront de déterminer la longévité du module TLC.

The Central Andes of northern Chile hosts many of the world’s largest porphyry copper deposits (PCDs). Copper in many of these deposits has been concentrated during near-surface, weathering-driven supergene enrichment, although the hyperarid Atacama Desert, which encompasses much of the region, is currently one of the driest places on Earth. Supergene enrichment is a three-stage process in which copper is liberated from sulphides during weathering, transported downward in solution and reprecipitated as secondary sulphides under reducing conditions beneath the water table. Thus, supergene profiles are typified by an upper zone of weathered rocks, leached of copper, and a subjacent enrichment blanket. The progression of weathering and associated enrichment of PCDs is thought to be controlled by the position of the water table relative to an exhuming orebody because sulphide oxidation, which produces the Fe-oxide minerals characteristic of leached caps and the acidic sulphate solutions necessary for copper leaching, is most efficient in the unsaturated zone. This project presents a geochronological study of alunite (a K-Al-sulphate by-product of acid leaching), and hematite (an Fe-oxide by-product of sulphide oxidation) to constrain the timing of weathering, enrichment and water table movement through the preserved supergene profiles of two Central Andean PCDs; Spence and Cerro Colorado. My results show that whilst enrichment at both deposits ended in the middle Miocene, consistent with strengthening aridity at this time, weathering and hematite formation continued until the Pleistocene – long after the onset of hyperaridity and burial of the deposits by post-exhumation gravel cover. The oxygen isotopic composition of hematite suggests that while meteoric water was present during weathering at Cerro Colorado, hematite at Spence formed in the presence of isotopically heavy formation water. Together with the geochronology results, the isotope data suggest that the ra

Per- and polyfluorinated alkyl substances (PFASs) are a class of man-made chemicals, which consist of a fluorinated carbon back bone and a functional group like a carboxylic acid, sulfonic acid, alcohol, etc. In outdoor wear side-chain fluorinated polymers (SFPs), which consist of polymers such as polyurethanes or acrylates with PFASs as side-chains, are used to obtain the required water and dirt repellence. In outdoor wear PFASs are present as impurities and as unreacted products of the production process of those SFPs. The study described in this thesis focused on PFASs present in textiles of outdoor wear. A method was first developed, optimized and validated for the analyses of perfluoroalkyl carboxylic acids (PFCAs) (C4-C14), and perfluoroalkane sulfonic acids (PFSAs) (C4, C6, C7, C8) in textiles. Extraction solvents, extraction duration and number of sequential extractions were optimized. The use of some PFASs has been restricted, and the regulation of more PFASs compounds is ongoing. The determine whether PFASs concentrations meet the safety standards, there is a need for reliable analytical methods. To avoid that reported concentrations are dependent on the quality of the analysis laboratory, an interlaboratory assessment was organized to assess the overall performance of laboratories worldwide. Participants could report PFAS concentrations in a test solution of the target compounds, and in six matrices (sediment, fish, human milk, human plasma, air extract, and water). The effects of weathering on PFASs from outdoor wear were assessed on thirteen commercial available textile samples with an SFP-based durable water repellent (DWR) coating. The concentrations of perfluoroalkyl acids (PFAAs) and volatile PFASs in the textiles were determined. After weathering (exposure to elevated ultra violet (UV) radiation, humidity and temperature) of the thirteen textile samples in an aging device for 300h, the samples were again analysed for their PFAS concentrations. Weat

Climate variables including temperature, rainfall intensity, rainfall acidity, and lithological properties are among the most important factors affecting rock weathering. However, the relative contribution of these four factors on rock weathering, especially on chemical weathering, is still unclear. In this study, we carried out a series of weathering-leaching rainfall simulations on four types of badland sediments under controlled conditions of two levels of temperature, rainfall intensity, and rainfall acidity based on the real field data from representative weather scenarios. The main objectives are 1) to explore the progressive change of sample surface and leachate characteristics and 2) to reveal the independent effects of temperature, rainfall intensity, rainfall acidity, and lithology and their relative contribution as well, on both mechanical and chemical weathering. Qualitative analysis on crack development and fragmentation of sample surface and quantitative analysis on the leachate volume, pH, electrical conductivity, and total cation and anion releases of sample leachate together demonstrated that for the investigated sediments, under the conditions of temperature, intensity, and acidity of rain that can be achieved in nature, high drying temperature obviously increases mechanical disintegration by promoting the rate and magnitude of moisture variations (wetting–drying alterations), while high rainfall intensity and acid rain have no obvious effect. Impact and importance of the drying process caused by high temperature between wetting events need more attention, rather than high rainfall intensity. Low temperature, high rainfall intensity, and acid rain contributing more hydrogen ions required for cation exchanges, rock type with more soluble minerals, all promote chemical weathering, and the influence of climatic and lithological factors on chemical weathering decreases in the following order: mineral composition＞ rainfall intensity ＞ temperature ＞ rain

Climate change is generally expected to have a positive effect on weathering rates, due to the strong temperature dependence of the weathering process. Important feedback mechanisms such as changes in soil moisture, tree growth and organic matter decomposition can affect the response of weathering rates to climate change. In this study, the dynamic forest ecosystem model ForSAFE, with mechanistic descriptions of tree growth, organic matter decomposition, weathering, hydrology and ion exchange processes, is used to investigate the effects of future climate scenarios on base cation weathering rates. In total, 544 productive coniferous forest sites from the Swedish National Forest Inventory are modelled, and differences in weathering responses to changes in climate from two Global Climate Models are investigated. The study shows that weathering rates at the simulated sites are likely to increase, but not to the extent predicted by a direct response to elevated air temperatures. Besides the result that increases in soil temperatures are less evident than those in air temperature, the study shows that soil moisture availability has a strong potential to limit the expected response to increased temperature. While changes in annual precipitation may not indicate further risk for more severe water deficits, seasonal differences show a clear difference between winters and summers. Taking into account the seasonal variation, the study shows that reduced soil water availability in the summer seasons will strongly limit the expected gain in weathering associated with higher temperatures.

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in James, B., de Vos, A., Aluwihare, L., Youngs, S., Ward, C., Nelson, R., Michel, A., Hahn, M., & Reddy, C. Divergent forms of pyroplastic: lessons learned from the M/V X-Press Pearl ship fire. ACS Environmental Au, 2(5), (2022): 467–479, https://doi.org/10.1021/acsenvironau.2c00020., In late May 2021, the M/V X-Press Pearl container ship caught fire while anchored 18 km off the coast of Colombo, Sri Lanka and spilled upward of 70 billion pieces of plastic or “nurdles” (∼1680 tons), littering the country’s coastline. Exposure to combustion, heat, chemicals, and petroleum products led to an apparent continuum of changes from no obvious effects to pieces consistent with previous reports of melted and burned plastic (pyroplastic) found on beaches. At the middle of this continuum, nurdles were discolored but appeared to retain their prefire morphology, resembling nurdles that had been weathered in the environment. We performed a detailed investigation of the physical and surface properties of discolored nurdles collected on a beach 5 days after the ship caught fire and within 24 h of their arrival onshore. The color was the most striking trait of the plastic: white for nurdles with minimal alteration from the accident, orange for nurdles containing antioxidant degradation products formed by exposure to heat, and gray for partially combusted nurdles. Our color analyses indicate that this fraction of the plastic released from the ship was not a continuum but instead diverged into distinct groups. Fire left the gray nurdles scorched, with entrained particles and pools of melted plastic, and covered in soot, representing partial pyroplastics, a new subtype of pyroplastic. Cross sections showed that the heat- and fire-induced changes were superficial, leaving the surfaces more hydrophilic but the interior relatively untouched. These results provide timely and actionable information to responders to reevaluate cleanup end points, monitor the recurrence of these spilled nurdles, gauge short- and long-term effects of the spilled nurdles to the local ecosystem, and manage the recovery of the spill. These findings underscore partially combusted plastic (pyroplastic) as a type of plastic pollution that has yet to be fully explored despite the frequency at which, This work was supported by the Postdoctoral Scholar Program at the Woods Hole Oceanographic Institution (WHOI), with funding provided by the Weston Howland Jr. Postdoctoral Scholarship. Additional support was provided by the WHOI Marine Microplastics Catalyst Program, the WHOI Marine Microplastics Innovation Accelerator Program, the WHOI Investment in Science Fund, the March Marine Initiative (a program of March Limited, Bermuda), The Seaver Institute, Gerstner Philanthropies, the Wallace Research Foundation, the Richard Saltonstall Charitable Foundation, the Harrison Foundation, Hollis and Ermine Lovell Charitable Foundation, and the Richard Grand Foundation. AdV was supported by funding from the Schmidt Foundation.