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The origin of hypogene alteration and mineralization features in the Escondida 27porphyry Cu deposit resulted from intense overprinting related to three main hydrothermal 28stages. The beginning of each stage is recorded by deposition of bright quartz crystals on 29vein walls that precipitated from high-temperature fluids. In the deepest zones of the 30deposit, the earliest stage started with exsolution of intermediate-density fluids, which 31transported high concentrations of Cu, whereas Mo was not detected. However, in the 32shallow zones, the early stage began with depressurization and unmixing of intermediate-33density fluids, which generated both a hypersaline and vapour-rich fluid phase, producing 34an important geochemical segregation between both phases. The transitional stage also 35started with circulation of intermediate-density fluids but never experienced unmixing. 36These fluids transported the highest Mo concentrations in the deposit; however, Cu displays 37lower concentrations relative to intermediate-density fluids from the early stage. The 38beginning of the late stage was also associated with intermediate-density fluids; however, 39Cu and Mo were below the detection limits in most of the analysed fluids. During the 40evolution of the three stages, the fluids experienced gradual cooling, which promoted the 41precipitation of euhedral and zoned quartz crystals that overgrew the early high-42luminescence quartz generations. Sometimes, sulfide minerals display euhedral crystal 43boundaries with zoned quartz, suggesting that mineralization started during these phases.44The latest events detected in each main stage are linked to cooler and low-salinity fluids, from which dark quartz and hypogene sulfide sprecipitated along microfractures and 46interstitial spaces developed in the earlier quartz generations.

The Upper Cretaceous carbonates along the Zagros thrust-fold belt “Harir-Safin anticlines” experienced extensive hot brine fluids that produced several phases of hydrothermal cements, including saddle dolomites. Detailed fluid inclusion microthermometry data show that saddle dolomites precipitated from hydrothermal (83–160 °C) and saline fluids (up to 25 eq. wt.% NaCl; i.e., seven times higher than the seawater salinity). The fluids interacted with brine/rocks during their circulation before invading the Upper Cretaceous carbonates. Two entrapment episodes (early and late) of FIs from the hydrothermal “HT” cements are recognized. The early episode is linked to fault-related fractures and was contemporaneous with the precipitation of the HT cements. The fluid inclusions leaked and were refilled during a later diagenetic phase. The late episode is consistent with low saline fluids (0.18 and 2.57 eq. wt.% NaCl) which had a meteoric origin. Utilizing the laser ablation U-Pb age dating method, two numerical absolute ages of ~70 Ma and 3.8 Ma are identified from calcrete levels in the Upper Cretaceous carbonates. These two ages obtained in the same level of calcrete indicate that this unit was twice exposed to subaerial conditions. The earlier exposure was associated with alveolar and other diagenetic features, such as dissolution, micritization, cementation, while the second calcrete level is associated with laminae, pisolitic, and microstromatolite features which formed during the regional uplifting of the area in Pliocene times. In conclusion, the hydrothermal-saddle dolomites were precipitated from high temperature saline fluids, while calcrete levels entrapped large monophase with very low salinity fluid inclusions, indicative for a low temperature precipitation from water with a meteoric origin.

This paper is based on a multidisciplinary field and laboratory study of carbonate concretions developed in poorly lithified Quaternary, syn-kinematic sediments along the Quattro Castella Anticline, Northern Apennines, Italy. The studied concretions consist of both tabular (parallel to bedding) and elongate single to coalescent concretionary bodies oriented at different angles to the bedding throughout the exposed stratigraphic succession. The dimensions of the concretions range from a few centimetres for single elongate concretions up to several metres for tabular to coalescent concretions. Field observations and petrophysical data indicate that the concretions developed preferentially in sediments characterized by mean grain sizes of 90–290 μm and a permeability ranging from 7 × 102 to 7 × 104 mD. Carbon and oxygen stable isotope analyses in conjunction with the petrographic investigations indicate that the precipitation of concretionary calcite occurred in a meteoric vadose realm during early eogenesis and subsequently in a meteoric phreatic environment. Diagenetic data and concretion patterns in syn-tectonic sediments suggest they formed during the lateral propagation of the anticline, which, in turn, promoted a change in the local topographic–hydraulic gradient from fold axial parallel to fold orthogonal. The integrated analysis of carbonate concretions provides a useful tool with which to unravel the palaeo-fluid flow history and therefore to predict fluid circulation patterns in folded siliciclastic rocks. Supplementary material: Complete isotopic data from both hand samples and thin sections, together with statistical analysis, scanning electron microscope cement images and grain size distributions with the standard operative procedure tests performed, and detailed permeability measurements are available at https://doi.org/10.6084/m9.figshare.c.4087019

The Lower Jurassic platform and basinal deposits exposed in the Montagna dei Fiori Anticline (Central Apennines, Italy) are pervasively affected by dolomitization. Based on the integration of field work, petrography, and geochemistry, two fault-related dolomitization events were recognized and interpreted as occurred before and during the Apenninic orogeny, respectively. Fluid inclusion analysis indicates moderate to elevated salinity values of 3.5 to 20.5 and 12.8 to 18.6 eq. wt. % NaCl, in the first and the second event, respectively. The estimated salinities, in combination with δ18O values and 87Sr/86Sr ratios, suggest significant involvement of evaporitic fluids in both events, most likely derived from the underlying Upper Triassic Burano Formation. In addition, the 87Sr/86Sr ratios up to 0.70963 suggest the circulation of deep-sourced fluids that interacted with siliciclastics and/or the crystalline basement during the dolomitization events. The first dolomitization event which is also considered as the most pervasive one started prior to the significant burial conditions, as reflected in homogenization temperatures of their fluid inclusions being mostly below about 40–50 °C. Two major dolomite types (D1 and D2) were recognized as pertaining to this event, both postdated by high amplitude bed-parallel stylolites. This relationship supports a syn-burial, pre layer-parallel shortening dolomitization, interpreted as controlled by the extensional fault pattern affecting the carbonate succession before its involvement in the Apenninic thrust wedge. A possible geodynamic framework for this dolomitization event is Early to Late Jurassic rift-related extensional tectonism. The second dolomitization event initiated with a dolomite type (D3) characterized by a slight temperature upturn (up to 73 °C), followed by a second type (D4) with markedly higher homogenization temperatures (up to 105 °C), interpreted as associated with the inflow of hydrothermal fluids, possibly related to major changes in the permeability architecture of faults during early- to syn-thrusting and folding activity. Eventually, D4 was overprinted by a late generation of dolomite veins (D5) interpreted as associated with late orogenic extensional faulting in the backlimb of the Montagna dei Fiori Anticline. Based on the timing of deformation in the Montagna dei Fiori Anticline, D3 to D5 dolomitization likely occurred in Late Miocene to Pliocene times. The findings regarding characteristics and timing of dolomitization here illustrates the long-term controlling role of the eveporitic detachments in dolomitization process. Our data shows the Mg-rich fluids most likely derived from these evaporites may prime the tectonically involved successions for repeated dolomitization, and formation of potential reservoirs in sequential tectonic modifications (extensional vs. compressional).

Payment for ecosystem services (PES) is commonly defined as a market-based environmental policy instrument to efficiently achieve ecosystem services provision. However, an increasing body of literature shows that this prescriptive conceptualization of PES cannot be easily generalized and implemented in practice, and that the commodification of ecosystem services (ES) is problematic and may lead to unfair situations for relevant PES actors. This paper synthesizes case studies in Indonesia, the Philippines and Nepal to provide empirical observations on emerging PES mechanisms in Asia. Lessons learned show that fairness and efficiency objectives must be achieved simultaneously in designing and implementing a sustainable PES scheme, especially in developing country contexts. Neither fairness nor efficiency is a primary aim but an intermediate 'fairly efficient and efficiently fair' PES may bridge the gap between PES theory and practice to increase sustainable ES provision and improve livelihoods. & 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

The Mars Science Laboratory rover Curiosity visited two active wind‐blown sand dunes within Gale crater, Mars, which provided the first ground‐based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial‐like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were present on all dune slopes and had a size and shape similar to their terrestrial counterpart. Grainfall and grainflow occurred on dune and large‐ripple lee slopes. Lee slopes were ~29° where grainflows were present and ~33° where grainfall was present. These slopes are interpreted as the dynamic and static angles of repose, respectively. Grain size measured on an undisturbed impact ripple ranges between 50 μm and 350 μm with an intermediate axis mean size of 113 μm (median: 103 μm). Dissimilar to dune eolian processes on Earth, large, meter‐scale ripples were present on all dune slopes. Large ripples had nearly symmetric to strongly asymmetric topographic profiles and heights ranging between 12 cm and 28 cm. The composite observations of the modern sedimentary processes highlight that the Martian eolian rock record is likely different from its terrestrial counterpart because of the large ripples, which are expected to engender a unique scale of cross stratification. More broadly, however, in the Bagnold Dune Field as on Earth, dune‐field pattern dynamics and basin‐scale boundary conditions will dictate the style and distribution of sedimentary processes., Key Points Impact ripples, grainfall, and grainflows occur on Martian dunes and are similar to terrestrial counterpartsUnique, meter‐scale large ripples are found on Martian dunes and would distinguish the Martian and terrestrial eolian rock recordsThe angle of repose on Martian dunes and large ripples is found to be around 29°, which is similar to that found on Earth

Non-avian dinosaurs went extinct 66 million years ago, geologically coincident with the impact of a large bolide (comet or asteroid) during an interval of massive volcanic eruptions and changes in temperature and sea level. There has long been fervent debate about how these events affected dinosaurs. We review a wealth of new data accumulated over the past two decades, provide updated and novel analyses of long-term dinosaur diversity trends during the latest Cretaceous, and discuss an emerging consensus on the extinction's tempo and causes. Little support exists for a global, long-term decline across non-avian dinosaur diversity prior to their extinction at the end of the Cretaceous. However, restructuring of latest Cretaceous dinosaur faunas in North America led to reduced diversity of large-bodied herbivores, perhaps making communities more susceptible to cascading extinctions. The abruptness of the dinosaur extinction suggests a key role for the bolide impact, although the coarseness of the fossil record makes testing the effects of Deccan volcanism difficult.

IgA nephropathy (IgAN), major cause of kidney failure worldwide, is common in Asians, moderately prevalent in Europeans, and rare in Africans. It is not known if these differences represent variation in genes, environment, or ascertainment. In a recent GWAS, we localized five IgAN susceptibility loci on Chr.6p21 (HLA-DQB1/DRB1, PSMB9/TAP1, and DPA1/DPB2 loci), Chr.1q32 (CFHR3/R1 locus), and Chr.22q12 (HORMAD2 locus). These IgAN loci are associated with risk of other immune-mediated disorders such as type I diabetes, multiple sclerosis, or inflammatory bowel disease. We tested association of these loci in eight new independent cohorts of Asian, European, and African-American ancestry (N = 4,789), followed by meta-analysis with risk-score modeling in 12 cohorts (N = 10,755) and geospatial analysis in 85 world populations. Four susceptibility loci robustly replicated and all five loci were genome-wide significant in the combined cohort (P = 5×10−32–3×10−10), with heterogeneity detected only at the PSMB9/TAP1 locus (I2 = 0.60). Conditional analyses identified two new independent risk alleles within the HLA-DQB1/DRB1 locus, defining multiple risk and protective haplotypes within this interval. We also detected a significant genetic interaction, whereby the odds ratio for the HORMAD2 protective allele was reversed in homozygotes for a CFHR3/R1 deletion (P = 2.5×10−4). A seven–SNP genetic risk score, which explained 4.7% of overall IgAN risk, increased sharply with Eastward and Northward distance from Africa (r = 0.30, P = 3×10−128). This model paralleled the known East–West gradient in disease risk. Moreover, the prediction of a South–North axis was confirmed by registry data showing that the prevalence of IgAN–attributable kidney failure is increased in Northern Europe, similar to multiple sclerosis and type I diabetes. Variation at IgAN susceptibility loci correlates with differences in disease prevalence among world populations. These findings inform genetic, biological, and epidemiological investigations of IgAN and permit cross-comparison with other complex traits that share genetic risk loci and geographic patterns with IgAN., Author Summary IgA nephropathy (IgAN) is the most common cause of kidney failure in Asia, has lower prevalence in Europe, and is very infrequent among populations of African ancestry. A long-standing question in the field is whether these differences represent variation in genes, environment, or ascertainment. In a recent genome-wide association study of 5,966 individuals, we identified five susceptibility loci for this trait. In this paper, we study the largest IgAN case-control cohort reported to date, composed of 10,775 individuals of European, Asian, and African-American ancestry. We confirm that all five loci are significant contributors to disease risk across this multi-ethnic cohort. In addition, we identify two novel independent susceptibility alleles within the HLA-DQB1/DRB1 locus and a new genetic interaction between loci on Chr.1p36 and Chr.22q22. We develop a seven–SNP genetic risk score that explains nearly 5% of variation in disease risk. In geospatial analysis of 85 world populations, the genetic risk score closely parallels worldwide patterns of disease prevalence. The genetic risk score also predicts an unsuspected Northward risk gradient in Europe. This genetic prediction is verified by examination of registry data demonstrating, similarly to other immune-mediated diseases such as multiple sclerosis and type I diabetes, a previously unrecognized increase in IgAN–attributable kidney failure in Northern European countries.

International audience; High albedo features are identified in association with barchan dunes in an equatorial inter-crater dune field on Mars using data from the High Resolution Imaging Science Experiment. This paper describes the morphometric properties of these features and their association with the present barchan dune field. We propose that these features are cemented aeolian deposits that form at the foot of the dune avalanche face. A possible terrestrial analog exists at White Sands National Monument, in south-central New Mexico, USA. The presence of these features suggests past episodes of dune migration in inter-crater dunefields and liquid water in the near sub-surface in sufficient quantity to cause the cementation of aeolian dune sediment.

We describe the geological, morphological, and climatic setting of the San Juan meteorite collection area in the Central Depression of the Atacama Desert (Chile). Our recovery activities yielded 48 meteorites corresponding to a minimum of 36 different falls within a 3.88 km(2) area. The recovery density is in the range 9-12 falls km(-2) depending on pairing, making it the densest among meteorite collection areas in hot deserts. This high meteorite concentration is linked to the long-standing hyperaridity of the area, the stability of the surface pebbles (> Ma), and very low erosion rates of surface pebbles (approximately 30 cm Ma(-1) maximum). The San Juan meteorite population is characterized by old terrestrial ages that range from zero to beyond 40 ka, and limited weathering compared with other dense collection areas in hot desert. Chemical weathering in San Juan is slow and mainly controlled by the initial porosity of meteorites. As in the Antarctic and other hot deserts, there is an overabundance of H chondrites and a shortage of LL chondrites compared with the modern falls population, suggesting a recent (< few ka) change in the composition of the meteorite flux to Earth.

Pennsylvanian phylloid algal reefs are widespread and well exposed in south Guizhou, China. Here we report on reefs ranging from 2 to 8 m thickness and 30–50 m lateral extension. Algae, the main components, display a wide spectrum of growth forms, but are commonly cyathiform (cup-shaped) and leaf-like (undulate plates). The algal reef facies is dominated by boundstone. Algal thalli form a dense carpet whose framework pores are filled with marine cement and peloidal micrite. The peloidal matrix is dense, partly laminated or clotted with irregular surfaces and often gravity defying. Algal reefs in Guizhou differ from examples reported to date by the high biodiversity of organisms other than phylloids: e.g., the intergrowth of algae with corals (some of which are twice the size of algal thalli) and numerous large brachiopods. This contrasts to previous views that phylloid algal “meadows” dominated the actual seafloor, excluding other biota. Also, the pervasive marine cements (up to 50%) including botryoidal cement are noteworthy. Algal reefs developed at platform margins, a depositional environment similar to that of modern Halimeda mounds in Java, Australia and off Bahamas, and to that of time- equivalent examples reported from the Canadian Arctic Archipelago. Whereas nutrients appear decisive in the growth of Halimeda reefs, algal reefs reported herein seemingly grew under conditions of low nutrient levels. Overall, algal reefs in Guizhou challenge previous views on growth forms, diversity patterns, and depositional environments and add to the spectrum of these partly puzzling biogenic structures.

Wind erosion is not as significant or a widespread problem in Europe as in dryer parts of the world, but it can cause major damage in small areas. The hazard is greatest in the lowlands of northwestern Europe with more than 3 million ha at high-potential wind erosion risk. Crop damage and off-site damage have prompted farmers and policymakers to pay more attention to wind erosion control. A great variety of measures have been developed in the last decades. Most fanners, however, only use measures to protect their high value crops. In existing policies, little attention is paid to the off-site effects and long-term effects of wind erosion. There are no direct policy measures at a European level to control soil erosion, and few measures exist in individual Member States. Agricultural or environmental EC policies offer different policy tools to approach the wind erosion problems related to agricultural practices. Tools like subsidies for the re-afforestation of arable land can help regional policy makers with the implementation of wind erosion control measures. A case study concerning the 'Code of Good Agricultural Practice' shows that regional differences result in different control measures that fits best given the physical, social and economic context. The formulation of the practical details of such code should therefore remain a task of the local or regional government. The main objectives of a Code of Good Agricultural Practice could be formulated at national or European level. (C) 2003 Elsevier Science B.V All rights reserved.