Geneva Basin Research Articles

Supersymmetry at a 28 TeV hadron collider: HE-LHC

The discovery of the Higgs boson at $\sim 125$ GeV indicates that the scale of weak scale supersymmetry is higher than what was perceived in the pre-Higgs boson discovery era and lies in the several TeV region. This makes the discovery of supersymmetry more challenging and argues for hadron colliders beyond LHC at $\sqrt s=14$ TeV. The Future Circular Collider (FCC) study at CERN is considering a 100 TeV collider to be installed in a 100 km tunnel in the Lake Geneva basin. Another 100 km collider being considered in China is the Super proton-proton Collider (SppC). A third possibility recently proposed is the High-Energy LHC (HE-LHC) which would use the existing CERN tunnel but achieve a center-of-mass energy of 28 TeV by using FCC magnet technology at significantly higher luminosity than at the High Luminosity LHC (HL-LHC). In this work we investigate the potential of HE-LHC for the discovery of supersymmetry. We study a class of supergravity unified models under the Higgs boson mass and the dark matter relic density constraints and compare the analysis with the potential reach of the HL-LHC. A set of benchmarks are presented which are beyond the discovery potential of HL-LHC but are discoverable at HE-LHC. For comparison, we study model points at HE-LHC which are also discoverable at HL-LHC. For these model points, it is found that their discovery would require a HL-LHC run between 5-8 years while the same parameter points can be discovered in a period of few weeks to $\sim 1.5$ yr at HE-LHC running at its optimal luminosity of $2.5\times 10^{35}$ cm$^{-2}$ s$^{-1}$. The analysis indicates that the HE-LHC possibility should be seriously pursued as it would significantly increase the discovery reach for supersymmetry beyond that of HL-LHC and decrease the run period for discovery.

Dolomitization of the Upper Jurassic carbonate rocks in the Geneva Basin, Switzerland and France

The Upper Jurassic carbonates represent important potential targeted reservoirs for geothermal energy in the Geneva Basin (Switzerland and France). Horizons affected by dolomitization, the focus of the present study, are of particular interest because they proved to be productive in time-equivalent deposits currently exploited in Southern Germany. The study is based on sub-surface samples and outcrops in the Geneva Basin. Petrographic analyses allowed to constrain the paragenesis of the Upper Jurassic units prior to discussing the cause(s) and effect(s) of dolomitization. Data reveal that the facies are affected by early and late diagenesis. All samples show at least two stages of burial blocky calcite cementation with the exception of those from the sub-surface, which display an incomplete burial blocky cementation preserving primary intercrystalline porosity. Dolomitization affected all units. The results point to an early dolomitization event, under the form of replacement dolomite. Dedolomitization, through calcitization and/or dissolution, is an important process, creating secondary pore space. Results of the present study favor a reflux model for dolomitization rather than the mixing-zone model suggested in earlier work. However, considering the geodynamic context, other dolomitization models cannot be excluded for the subsurface. The presence of secondary pore space might contribute to the connectivity of the porous network providing enhanced reservoir properties. These results are a first step towards a better understanding of the diagenetic history of the Upper Jurassic in the Geneva Basin. Moreover, it provides a reasonable framework for further geochemical analyses to constrain the nature and timing of fluid migration. The paragenesis and the dolomitization model hold the potential to help in ongoing exploration for geothermal energy beyond the Geneva Basin.

Origin and paleoenvironmental significance of Fe Mn nodules in the Holocene perialpine sediments of Geneva Basin, western Switzerland

Abstract Perialpine areas of central Europe have undergone significant changes following the last Alpine glaciation and especially through the Holocene time. This study relies on geochronological, mineralogical and geochemical clues to explain the formation and paleoenvironmental significance of Fe Mn nodules reported from the young soils (~4.5 ka BCE) of Geneva Basin in western Switzerland. Having on average 2 mm in diameter, the nodules usually possess an onion-like and quasi-layered internal architecture defined by selective enrichments in Fe and Mn. Fe-rich mica is largely present in soil matrix and has served as a main source of Fe and Mn. Susceptible to favourable Eh-pH conditions several steps in mica weathering were recognised leading to the formation of nodules – vermiculitization, microcracking, Fe Mn segregation and re-precipitation. Mineral alterations were boosted by long periods of summer warm climate during Boreal and Atlantic times as suggested by the increasing illite-smectite content and a disappearance of hydroxyl-interlayered clays from analysed colluvium. Moreover, archaeological ages and radiocarbon dating of charcoal yielded coherent Fe Mn encrustation ages (4.8–4.3 ka BCE and 4.5–4.4 ka BCE, respectively) that coincide with the Holocene temperature maximum (~4 ka BCE) in Central Europe. Terrain morphology that led to better water retention formed earlier than ~8 ka BCE ago, during undefined Late Glacial time, promoting seasonal changes in redox conditions, thus facilitating the mobilization, distribution and re-precipitation of Fe and Mn. Established conditions lasted until Late Neolithic (3.4–2.2 ka BCE) when different agricultural practices changed favourable hydromorphic environment effectively putting an end to further nodule formation.

Evaluation de la fonctionnalité des corridors de déplacement du cerf dans le bassin genevois

Assessment of the functionality of wildlife corridors used by red deer in the Geneva basin The red deer population located west of the Jura Mountains is expanding its range. For the past fifteen years this expansion has also affected the lowlands of the Geneva basin. When entering the Plateau area, the red deer face a landscape highly fragmented by urbanisation. In addition their natural habitats are broken up and are often reduced to small patches. In this context it is hard to imagine how a red deer population manages to find all the resources required for survival, and how the animals manage to connect the scattered habitats in their area. A study was initiated in 2009 in order to assess this population's use of the space available. Sixteen individuals were fitted with GPS collars in order to monitor their movements. The results show that these individuals manage to connect a set of habitats, forests and agricultural areas, thanks to the presence of transit corridors, the whole system forming a network superposed on the urban network. It was however observed that the functionality of these corridors is often threatened and that their size has been reduced in the last decade. However, even though the landscape matrix is dominated by agricultural environments and is strongly fragmented, the animals are, at present, able to find enough resources by moving between habitat patches using the network which remains. The area thus used to satisfy their essential needs is surprisingly small.

Landscape effects on wild boar home range size under contrasting harvest regimes in a human-dominated agro-ecosystem

Agro-ecosystems can experience elevated human-wildlife conflicts, especially crop damage. While game management often aims at reducing number to mitigate conflicts, there is on-going debate about the role of hunting disturbance in promoting game to range over wider areas, thereby potentially exacerbating conflicts. Herein, we hypothesised that landscape configuration and non-lethal disturbance modulate the response to harvest disturbance. We used an information theoretic approach to test the effects of landscape and anthropogenic variables on wild boar ranging patterns across contrasting harvest regimes. We used 164 seasonal home ranges from 95 wild boar (Sus scrofa) radio-tracked over 6 years in the Geneva Basin where two main harvest regimes coexist (day hunt and night cull). Mean seasonal 95% kernel home range size was 4.01 ± 0.20 km2 (SE) and 50% core range size 0.79 ± 0.04 km2, among the smallest recorded in Europe. Range sizes were larger in the day hunt area than in the night cull area, with no seasonal effect. However, when accounting for landscape variables, we demonstrate that these patterns were likely confounded by the underlying landscape configuration, and that landscape variables remain the primary drivers of wild boar ranging patterns in this human-dominated agro-ecosystem with range size best explained by a model including landscape variables only. Therefore, we recommend accounting for landscape configuration and sources of non-lethal disturbance in the design of harvest strategies when the aim is to limit wide-ranging behaviour of wild boar in order to mitigate conflicts.

Beyond the Large Hadron Collider: A First Look at Cryogenics for CERN Future Circular Colliders

Following the first experimental discoveries at the Large Hadron Collider (LHC) and the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. The study, conducted with the collaborative participation of interested institutes world-wide, considers several options for very high energy hadron-hadron, electron-positron and hadron-electron colliders to be installed in a quasi-circular underground tunnel in the Geneva basin, with a circumference of 80 km to 100 km. All these machines would make intensive use of advanced superconducting devices, i.e. high-field bending and focusing magnets and/or accelerating RF cavities, thus requiring large helium cryogenic systems operating at 4.5 K or below. Based on preliminary sets of parameters and layouts for the particle colliders under study, we discuss the main challenges of their cryogenic systems and present first estimates of the cryogenic refrigeration capacities required, with emphasis on the qualitative and quantitative steps to be accomplished with respect to the present state-of-the-art.

Predator–prey spatial game as a tool to understand the effects of protected areas on harvester–wildlife interactions

No-take reserves are sometimes implemented for sustainable population harvesting because they offer opportunities for animals to spatially avoid harvesters, whereas harvesters can benefit in return from the reserve spillover. Here, we used the framework of predator-prey spatial games to understand how protected areas shape spatial interactions between harvesters and target species and determine animal mortality. In these spatial games, the "predator" searches for "prey" and matches their habitat use, unless it meets spatial constraints offering the opportunity for prey to avoid the mortality source. However, such prey refuges could attract predators in the surroundings, which questions the potential benefits for prey. We located, in the Geneva Basin (France), hunting dogs and wild boar Sus scrofa L. during hunting seasons with global positioning systems and very-high-frequency collars. We quantified how the proximity of the reserve shaped the matching between both habitat uses using multivariate analyses and linked these patterns to animals' mortality with a Cox regression analysis. Results showed that habitat uses by both protagonists disassociated only when hunters were spatially constrained by the reserve. In response, hunters increased hunting efforts near the reserve boundary, which induced a higher risk exposure for animals settled over the reserve. The mortality of adult wild boar decreased near the reserve as the mismatch between both habitat uses increased. However the opposite pattern was determined for younger individuals that suffered from the high level of hunting close to the reserve. The predator-prey analogy was an accurate prediction of how the protected area modified spatial relationships between harvesters and target species. Prey-searching strategies adopted by hunters around reserves strongly impacted animal mortality and the efficiency of the protected area for this harvested species. Increasing reserve sizes and/or implementing buffer areas with harvesting limitations can dampen this edge effect and helps harvesters to benefit durably from source populations of reserves. Predator-prey spatial games therefore provide a powerful theoretical background for understanding wildlife-harvester spatial interactions and developing substantial application for sustainable harvesting.

Analytical Electron-Microscopy Fractionation of Fine and Colloidal Particulate-Phosphorus in Riverbed and Suspended Sediments

The impact particulate-phosphorus (particulate-P) has on eutrophication of aquatic systems that greatly depends on its composition. As a result, analysis methods for evaluating particulate-P speciation must be capable of identifying and/or quantifying the wide range of forms particulate-P can take. In the present study, we compare the particulate P speciation of the fine and colloidal fractions of riverbed sediment and suspended matter from two rivers in the Lake Geneva basin (French Alps) as determined with chemical extractions to results of a combined Transmission Electron Microscopy and Energy Dispersive Detection (TEM–EDS) analysis of the same samples. TEM–EDS provides semi-quantitative information about the distribution of P throughout the solid fraction of a sample and on the diversity of carrier phases, which are identified by their morphology and stochiometry. EDS-detectable quantities of phosphorus were found in 15–35% of the particles in the samples analyzed. As expected, particulate-P existed in a wide variety of forms, mostly associated with Al, Fe, Ca and Si. Some types of particles, often well-crystallized phosphate minerals, had high P contents (10–30%), but the dominant carrier phases of P were diffuse matrices of particles with low P contents (<5%). These matrices had a wide range of chemical compositions and included clay minerals, crystallized and amorphous phases of Fe, as well as intermediary components. Classical chemical extractions showed major differences in P content and speciation between the upstream and downstream sediment samples. The downstream samples showed higher frequencies of particles containing P, a larger diversity of carrier phases, a higher contribution of clays as carrier phases of P, and the presence of a new fraction with Al and Fe amorphous minerals. The processes that create and select carrier phases of particulate-P are part of the general dynamics of P within a watershed.

Genetic analysis of potential postglacial watershed crossings in Central Europe by the bullhead (Cottus gobioL.)

Natural colonizations across watersheds have been frequently proposed to explain the present distributions of many freshwater fish species. However, detailed studies of such potential watershed crossings are still missing. Here, we investigated potential postglacial watershed crossings of the widely distributed European bullhead (Cottus gobio L.) in two different areas along the Rhine-Rhône watershed using detailed genetic analysis. The main advantage of studying bullheads vs. other freshwater fish species is that their distribution has been lightly influenced by human activities and as such, interpretations of colonization history are not confounded by artificial transplantations. The genetic analyses of eight microsatellite loci revealed strong genetic similarities between populations of both sides of the Rhine-Rhône watershed in the Lake Geneva area, giving strong evidence for a natural watershed crossing of bullheads from the upper Rhine drainage into the Rhône drainage in the Lake Geneva area likely facilitated by the retreat of the glaciers after the last glacial maximum some 20,000 years ago. Populations from the Lake Geneva basin were genetically more similar to populations from across the watershed in the upper Rhine drainage than to populations further downstream in the lower Rhône. In contrast, populations from Belfort, an area, which was not covered by ice during the last glacial maximum, showed strong genetic differentiation between populations of the upper Rhine and Rhône drainages. Based on our results on the bullhead, we propose that glacial retreat may have eased the dispersal of numerous European freshwater fish species across several geological boundaries.

Conditions of contract for the CERN underground works

In 1995 the European Organization for Nuclear Research (CERN) launched a call for tender for the design and supervision of the civil engineering required as part of the construction of the next generation particle accelerator termed the Large Hadron Collider (LHC). Today, at the end of 2003, over 85% of the construction work has been completed at a cost of around 500 million Swiss Francs. Seven new shafts have been excavated along with four very large caverns and numerous smaller tunnels and galleries. These structures which have been excavated in the weak molasse rock of the Geneva Basin have pushed the design and construction skills of the European tunneling industry to their limit. Detailed design work commenced in April 1996 with three consortiums representing companies from six European states participating. The consultants were selected following a ''two envelope'' bidding process. Construction commenced in March 1998 with all four construction contracts up and running by the end of 1998. Four contracts were awarded for the construction work as detailed in the table below. In addition to these main construction contracts, numerous smaller contracts were also awarded mainly for consolidation works of existing infrastructure as well as specialized works such as site investigation, concrete drilling, etc. Whilst the success of the project has largely due to the skill, determination and hard work of client, designer and contractor alike, some recognition for the success of the project must also be attributable to the contractual framework within which the works were carried out. From the outset, CERN wished to set up a contractual framework that encouraged competitive bidding, enabled fair bidding between companies from various European states, allow quick and cheap dispute resolution and most importantly, were compatible with CERN's specific internal purchase and contract procedures that apply as a result of CERN's status as an international organization. This paper shall discuss the specific Conditions of Contract used for the construction contracts. The development from a standard FIDIC ''Red Book'' contract into four unique contracts shall be explained with the reasons why these modifications and developments were necessary. Lastly, the successes and failures of specific features of the contracts shall be presented and discussed. (A) Reprinted with permission from Elsevier. For the covering abstract see ITRD E124500.

Phylogeographic history of the land snail Candidula unifasciata (Helicellinae, Stylommatophora): fragmentation, corridor migration, and secondary contact.

We studied sequence variation in 16S rDNA in 204 individuals from 37 populations of the land snail Candidula unifasciata (Poiret 1801) across the core species range in France, Switzerland, and Germany. Phylogeographic, nested clade, and coalescence analyses were used to elucidate the species evolutionary history. The study revealed the presence of two major evolutionary lineages that evolved in separate refuges in southeast France as result of previous fragmentation during the Pleistocene. Applying a recent extension of the nested clade analysis (Templeton 2001), we inferred that range expansions along river valleys in independent corridors to the north led eventually to a secondary contact zone of the major clades around the Geneva Basin. There is evidence supporting the idea that the formation of the secondary contact zone and the colonization of Germany might be postglacial events. The phylogeographic history inferred for C. unifasciata differs from general biogeographic patterns of postglacial colonization previously identified for other taxa, and it might represent a common model for species with restricted dispersal.

PHYLOGEOGRAPHIC HISTORY OF THE LAND SNAIL CANDIDULA UNIFASCIATA (HELICELLINAE, STYLOMMATOPHORA): FRAGMENTATION, CORRIDOR MIGRATION, AND SECONDARY CONTACT

We studied sequence variation in 16S rDNA in 204 individuals from 37 populations of the land snail Candidula unifasciata (Poiret 1801) across the core species range in France, Switzerland, and Germany. Phylogeographic, nested clade, and coalescence analyses were used to elucidate the species evolutionary history. The study revealed the presence of two major evolutionary lineages that evolved in separate refuges in southeast France as result of previous fragmentation during the Pleistocene. Applying a recent extension of the nested clade analysis (Templeton 2001), we inferred that range expansions along river valleys in independent corridors to the north led eventually to a secondary contact zone of the major clades around the Geneva Basin. There is evidence supporting the idea that the formation of the secondary contact zone and the colonization of Germany might be postglacial events. The phylogeographic history inferred for C. unifasciata differs from general biogeographic patterns of postglacial colonization previously identified for other taxa, and it might represent a common model for species with restricted dispersal.

Genetic variation in the Italian crested newt, Triturus carnifex, and the origin of a non-native population north of the Alps

Genetic variation over 40 protein loci and 46 populations representing three taxa of crested newts revealed moderate genetic distances between Triturus carnifex carnifex, T. c. macedonicus and T. cristatus. Two populations from the Geneva Basin (presumed to be introduced) were genetically similar to T. c. carnifex and dissimilar to T. c. macedonicus and T. cristatus, showing that they belong to T. c. carnifex and not to native T. cristatus. A significant pattern of spatial genetic variation was found within T. c. carnifex along a north to south axis, from Croatia to Calabria. The Genevan populations showed highest genetic similarity with T. carnifex from Tuscany, suggesting that the propagule originated from that area. Effects of a population genetic bottleneck associated with the introduction could not be documented. The observed high allelic variation in Genevan T. c. carnifex could not be directly explained by introgression from T. cristatus. Comparisons across the range, including zones of hybridization within the T. cristatus superspecies, indicated that some alleles typical for the Genevan population may represent the so-called `hybrizymes'.

La formation de Montfleury près de Genève: étude palynologique et sédimentologique d'une séquence du Pléistocène moyen

In the Geneva basin a 127.3 m deep coring was carried out in the plain of Montfleury in order to get information about hydrogeology, lithology and chronology of the quaternary deposits. Palynostratigraphic studies on the so-called `'Marnes a lignite'' underlying the `'Alluvion ancienne'' revealed two interglacial sequences (Montfleury and Confignon). The Montfleury sequence belongs to the penultimate interglacial (Holstein sensu Welten 1988), the Confignon sequence must be assigned to a preceding interglacial. The chronostratigraphic position of the `'Alluvion ancienne'', which until now was believed to correspond to the Early-Wurm, must be revised.

Phytoplankton Utilization of Phosphorus Bound to Suspended Sediments from Selected Tributaries to Lake Geneva

Bioassays with natural phytoplankton exposed to suspended sediments were carried out to assess the effect of phosphorus associated with particles on algal productivity. Sediments were recovered in 1988 and 1989 by continuous flow centrifugation of water samples taken at the mouth of the major rivers in the Lake Geneva basin (Rhone, Dranse, Venoge and A ubonne) and at the effluent of the sewage treatment plant (STP) at Vidy-Lausanne. Sediment samples were analyzed for the forms of phosphorus (total P, organic P, apatite P, and non-apatite inorganic P) and used in an algal fractionation bioassay, involving a 3.5 hour incubation of lake phytoplankton in direct contact with the sediment. Change in growth rate in the > 20 μm and < 20 μm algal size fractions was measured by 14C uptake following filtration and dimethyl sulfoxide extraction, and compared to a lake water control. Results showed that the enhancement of algal uptake induced by the sediment P varies with river and the limnological conditions in the lake. Phytoplankton utilization of particulate nutrients appeared to proceed when soluble P in lake water dropped below a threshold of about 14 μg/L. This finding has significant implications for the direct involvement of particle associated P in primary production in lakes of differing trophic status. No growth was observed upon the addition of sediments from the Rhone River or the STP due to low concentrations of NAIP in the Rhone and to probable toxicity in the STP effluent. Growth was promoted with sediments from the Dranse and the Venoge in 1988, but inhibition occured with Venoge samples in 1989. The river at this time was characterized by low flow resulting in increased concentrations of toxic substances derived from STPs in the watershed. This study thus demonstrates the net effects or interaction of sediment associated nutrients and contaminants on phytoplankton productivity.

Forms of Particulate Phosphorus and the Sediment Carbon/Nitrogen Ratio as Indicators of Phosphorus Origins in Aquatic Systems

Abstract An evaluation has been carried out on the composition of sediment from a number of different environments in Lake Geneva basin (Switzerland) and compared to Lake Erie sediment, specifically on the forms of phosphorus and the C/N ratio. Compositional features and progressive spatial and temporal changes in composition have been used to define origins of phosphorus and organic matter and to elucidate both river and lake processes. Lake Geneva bottom sediment clearly represents a compositional continuum from the mixing of the mineralized product of primary production (C/N ratio 8–10) in the water column with allochthonous sediment derived predominantly from the upper Rhone River (C/N ratio 12–17). Analysis of the sediment in the effluent of a number of sewage treatment plants gave very high levels of phosphorus, particularly non-apatite inorganic phosphorus and C/N ratios from 6.7 to 9. Changes in composition in the sediments of storm driven rivers were related to the variable influences of point and diffuse sources as they respond to climatic variation and to land use and human population in the basins.

ΣDDT, PCBs, and HCB in the sediments of Lake Geneva and the upper Rhône River

Eighty surface sediment samples taken in 1978 from Lake Geneva, together with two cores sampled in 1976 and 1980, and 30 samples (1978) from the Rhone River were analyzed for organochlorine compounds. DDT, its metabolites (DDE, TDE), HCB, and PCB were found. No other organochlorine compound was identified at the detection level of 0.5 ppb. DDT metabolites were widespread and indicated residual DDT sources in the Rhone watershed and other minor lake tributaries, particularly on the Swiss coast. DDT levels have declined since an apparent peak usage in 1957. HCB was found in almost all samples. It first appeared about 1962 with consistent usage to the present. Use is widespread with the major source being the Rhone River. PCB was found in all samples at levels comparable to levels in the North American Great Lakes. Sources appear to be diffuse urban/industrial, with major inputs on the Swiss shore between Vevey and Morges. Peak use of PCB occurred in 1972 and was followed by a decline to 1978, with some evidence for a second increase to 1980, the latest sample available. Both HCB and PCB were found at high levels in the most upstream samples of the Rhone River which may be indicative of substantial atmospheric loadings of these two compounds to the Lake Geneva Basin.