New fieldwork and tectonic analysis has been carried out along the Andean morphotectonic frontline between 46°30’ and 47°30′S. The right lateral transtensional Marques–Zeballos Pass fault system (MZPRS) controlled the 800–1200 m uplift of the Andes at 16.1–18.1 Ma. Our data and analysis indicate that there was no lower Miocene contractile event along the Andean morphotectonic frontline. The Main Andean Thrust (MAT), which is deeply rooted in the upper crust is a retroarc thrust dipping 10–15° westward, and provides evidence for major crustal shortening at ~120 Ma. At that time the arc volcanic strata of the Ibañez Fm (148–178 Ma) was transported eastward above the rift volcanic Quemado Fm (144179 Ma), which lies unconformably on the Deseado basement massif.

Les rejets industriels dangereux liquides sont inevitables malgre l’existence de mesures preventives de reduction a la source. Les filieres de traitement de ces rejets visent differents objectifs : permettre leur recyclage total ou partiel, faciliter leur valorisation matiere ou energetique, permettre leur retour « ecocompatible » dans l’environnement ou encore les decomposer, plus ou moins completement, en especes chimiques plus « inoffensives ». Ces filieres necessitent la mise en œuvre de techniques tres variees qui relevent de differentes disciplines scientifiques : thermique, mecanique, physique, chimie, physico-chimie ou biologie. Le present article est relatif aux techniques chimiques et physico-chimiques pour le cas des dechets dangereux liquides issus de l’industrie.

Underlying the scientific method developed by Thorndycraft et al. (2019, T19 hereafter) for the morphological analysis is the idea that producing a large enough landform dataset treated statistically would facilitate quantification of regional isostatic rebound together with the reconstruction of the Lago Chalenko paleolake history. Also, they associate the landform dataset to a Bayesian modeling of ages. This Comment adresses 5 key points questionning the proposed assumptions. (C) 2019 Published by Elsevier Ltd.

The Cap des Trois Fourches (Eastern Rif, northern Morocco) metamorphic basement exposes two major tectonic units, namely the Taidant unit underthrusting the overlying Tarjat tectonic unit. The Tarjat tectonic unit is composed of metamorphic rock originating from detrital material. This upper Tarjat tectonic unit exhibits: (1) orthogneiss bodies being Paleozoic in age and (2) evidences showing a retromorphose during the Alpine orogenesis. U-Pb SHRIMP zircon geochronology from the orthogneiss bodies has yielded Sakmarian (early Permian) ages for the intrusion of their protoliths. The lower Taidant unit is formed of green and brown shales associated with quartzite beds. A Mesozoic age is commonly accepted for this unit. The internal structure of the Tarjat tectonic unit consists in km-scale folds trending ENE-WSW with an up-dip direction towards the SE. This compressional deformational stage was superimposed on internal thrust sheets controlled by ductile shear zones with a SW-vergent transport sense. The lower Taklant unit shows conspicuous bedding associated with a penetrative foliation outlining a monocline structure dipping gently towards the NW. The major ductile-brittle detachment fault bounding the upper Tarjat tectonic unit from the lower Taidant unit -i.e. the local basement exhibits evidences for a top-to-the-west sense of motion. We assume that this specific fault is the prolongation into the Cap des Trois Fourches area of the extensional detachment previously described in the Temsamane area. Therefore, this low angle detachment fault is a major tectonic element extending hundreds of km through the Eastern Rif. We postulate that this major detachment roots deep in the Eastern Rif basement. This detachment is cut at the surface by the Nekor normal-sinistral strike-slip fault that separates thin 24-32 km thick metamorphic Eastern Rif crust from the 50-55 km thick crust of the Western Rif. This transtensive fault system exhumes the Rif middle crust, represented by the Temsamane massif units, along the Nekor sinistral STEP boundary at the southern edge of the Betic-Rif subduction system.

En la región de la presa de Santa Rosa existen evidencias de una zona de falla de desplazamiento lateral izquierdo, cuya dirección es N30°W… Para continuar, descargue el artículo completo en PDF.

We present geomorphic, stratigraphic, and chronological data acquired along the General Carrera–Buenos Aires (GCBA) glacial lake located along a major morphological incision across the Andes. Complementing relevant available data, relative chronology of morphoclimatic records together with 18 10Be cosmic ray exposure ages allow constraining the timing of the Patagonian ice sheet fluctuations since the last glacial maximum. It improves the knowledge of Patagonia climate evolution in the 46°–48°S area and allows documenting the uplift rates (glacial rebound) for the past ∼7–9 ka. The first major ice lobe retreat occurred after 17.3 ± 0.6 ka and has likely continued during the Antarctic cold reversal from ∼12.9 to 14.5 ka. Between ∼12.9 and ∼10.9 ± 1.3 ka, the General Carrera Lake evolved as an endorheic basin. Terraces T4–T1 (top to bottom) have recorded abrupt lake regressions likely controlled by rainfall deficit. They have accumulated in the time interval ∼17.3–12.3 ka (maximum limits). Two glacial re-advances at ∼10.9 ± 1.3 and ∼7.9 ± 1.1 ka marked a major climate change that led the lake to be ice dammed again. A major transgression occurred that subsequently flooded the previously accumulated terraces. Since then, a pervasive regression has steered the GCBA Lake to the situation at present. The highest shoreline of the transgression is used as a passive marker in order to quantify the magnitude and character of the regional deformation. At long 72°30′W, the GCBA Lake area uplifted (glacial rebound) at a rate between 15 and 33.5 mm yr−1 during the past ∼7.9 ± 1.1 ka. We infer that the high uplift rate mainly originates from the North Patagonian icefield ice loss.

This paper aggregates the main basic data acquired along the Chile Triple Junction (CTJ) area (45°–48°S), where an active spreading center is presently subducting beneath the Andean continental margin. Updated sea-floor kinematics associated with a comprehensive review of geologic, geochemical, and geophysical data provide new constraints on the geodynamics of this puzzling area. We discuss: (1) the emplacement mode for the Pleistocene Taitao Ridge and the Pliocene Taitao Peninsula ophiolite bodies. (2) The occurrence of these ophiolitic complexes in association with five adakite-like plutonic and volcanic centers of similar ages at the same restricted locations. (3) The inferences from the co-occurrence of these sub-coeval rocks originating from the same subducting oceanic lithosphere evolving through drastically different temperature–pressure ( P – T ) path: low-grade greenschist facies overprint and amphibolite-eclogite transition, respectively. (4) The evidences that document ridge-jump events and associated microplate individualization during subduction of the SCR1 and SCR-1 segments: the Chonos and Cabo Elena microplates, respectively. The ridge-jump process associated with the occurrence of several closely spaced transform faults entering subduction is controlling slab fragmentation, ophiolite emplacement, and adakite-like production and location in the CTJ area. Kinematic inconsistencies in the development of the Patagonia slab window document an 11- km westward jump for the SCR-1 spreading segment at ~6.5-to-6.8 Ma. The SCR-1 spreading center is relocated beneath the North Patagonia Icefield (NPI). We argue that the deep-seated difference in the dynamically sustained origin of the high reliefs of the North and South Patagonia Icefield (NPI and SPI) is asthenospheric convection and slab melting, respectively. The Chile Triple Junction area provides the basic constraints to define the basic signatures for spreading-ridge subduction beneath an Andean-type margin.

During the Chile Triple Junction (CTJ) cruise, geophysical surveys were conducted between 45 degrees S and 48 degrees S, in the region of the Chile Triple Junction (CTJ), where the Nazca and Antarctica Plates are subducting beneath the South American Plate. Near the CTJ, the South Chile Rise (SCR), which separates the Nazca and Antarctica lower plates, consists of three spreading segments trending similar to N160 degrees, separated by a series of parallel fracture zones. The active spreading centers of the three segments consist of grabens with various widths and depths, bounded by steep fault scarps. We provide robust data showing that the SCR recorded remote and long-term effects of ridge subduction far from the subduction front. Magnetic profiles, multibeam bathymetric, and seismic data were acquired at intervals of 13 km along a N80 degrees E direction across the SCR during the CTJ cruise of R/V L'Atalante. Deformation of the oceanic lithosphere includes (1) a segmentation of the spreading axes along strike, (2) some ridge jumps, and (3) local constriction and changes in trend of the fracture zone valleys. Off-axis volcanism is observed in places that may suggest a link with an abnormal stress field induced by ridge subduction. The tectonic and volcanic anomalies, which occurred in response to the subduction of the SCR1 axis, may be correlated with geochemical anomalies and slab fragmentation recognized by previous works.

The Beni Bousera peridotite massif and its metamorphic surrounding rocks have been analyzed by the fission track (FT) method. The aim was to determine the cooling and uplift history of these mantle and associated crustal rocks after the last major metamorphic event that dates back to the Lower Miocene–Upper Oligocene time (∼22–24 Ma). The zircon FT analyses give an average cooling—i.e., below 320 °C—age of ∼19.5 Ma. In addition, the apatite FT data give an average cooling—i.e., below 110 °C—age of ∼15.5 Ma. Taking into account the thermal properties of the different thermochronological systems used in this work, we have estimated a rate of cooling close to 50 °C/Ma. This cooling rate constrains a denudation rate of about ∼2 mm year−1 from 20 to 15 Ma. These results are similar to those determined in the Ronda peridotite massif of the Betic Cordilleras documenting that some ultrabasic massifs of the internal zones of the two segments of the Gibraltar Arc have a similar evolution. However, Burdigalian sediments occur along the Betic segment (Alozaina area, western Betic segment) unconformably overlying peridotite. At this site, ultramafic rock was exposed to weathering at ages ranging from 20.43 to 15.97 Ma. Since the Beni Bousera peridotite was still at depth until 15.5 Ma, we infer that no simple age projection from massif to massif is possible along the Gibraltar Arc. Moreover, the confined fission track lengths data reveal that a light warming (∼100 °C) has reheated the massif during the Late Miocene before the Pliocene–Quaternary tectonic uplift.

Gravimetric and geologic data show that the reactivation of the Neogene Interandean depression and/or the ~75 - 65 Ma ophiolite suture into the modern dynamic of the Andes controlled the Gulf of Guayaquil Tumbes basin (GGTB) location and evolution during the past 1.8 - 1.6 Myr at least. Depending on whether the remobilization occurred along the interandean depression or the ophiolite suture, the GGTB evolved trough pure or simple shear mechanisms, respectively. Because the GGTB exhibits an along strike tectonic asymmetry associated with a pervasive seismic gap, the simple shear solution is more likely. Tectonic inversion occurred along a mid-crust detachment (the Mid-Crust detachment hereafter) matching the ophiolite suture that accommodates the North Andean Block (NAB) northward drift. The so-called Decoupling Strip located at the shelf slope break accommodated the tensional stress rotation from N-S along the shelf area i.e. NAB-drift induced to E-W along the continental margin i.e. subduction-erosion-induced. The landward dipping Woollard detachment system located at the Upper-Lower slope boundary connects the subduction channel at depth, allowing the Upper slope to evolve independently from the Lower slope wedge. The long-term recurrence interval between earthquakes, the strong interplate coupling, and the aseismic creeping deformation acting along the main low-angle detachments i.e. the Woollard and the Mid-Crust detachments may account for the pervasive seismic gap at the GGTB area. Because the subduction channel exhibits no record of significant seismic activity, no evidence exists to establish a link between the GGTB sustained subsidence and a basin-centered asperity. Because the GGTB is a promising site of hydrocarbon resources, to understand processes at the origin of this escape-induced forearc basin has a major economic interest.

To guarantee sustainable and dynamic waste management, the dynamic waste management approach (DWM) suggests an evolutionary new approach that maintains a constant flow towards the most favourable waste treatment processes (facilities) within a system. To that end, DWM is based on the law of conservation of energy, which allows the balancing of a network, while considering the constraints of incoming (h1 ) and outgoing (h2 ) loads, as well as the distribution network (ΔH) characteristics. The developed approach lies on the identification of the prioritization index (PI) for waste generators (analogy to h1 ), a global allocation index for each of the treatment processes (analogy to h2 ) and the linear index load loss (ΔH) associated with waste transport. To demonstrate the scope of DWM, we outline this approach, and then present an example of its application. The case study shows that the variable monthly waste from the three considered sources is dynamically distributed in priority to the more favourable processes. Moreover, the reserve (stock) helps temporarily store waste in order to ease the global load of the network and favour a constant feeding of the treatment processes. The DWM approach serves as a decision-making tool by evaluating new waste treatment processes, as well as their location and new means of transport for waste.

The life cycle of a product is generally characterized by the main following stages: raw materials acquisition, manufacturing, processing and formulation, distribution and transportation, use, re-use, maintenance, recycle and waste management. As regards the process, the following stages are usually distinguished: raw materials acquisition, process manufacture, use and dismantling at the end of the lifetime. Considering the life cycle concept in a risk analysis approach requires the adjustment of the classic risk analysis methodology. In order to build up this new methodology called LCRA (Life Cycle Risk Assessment), we relied on the LCA (Life Cycle Assessment) methodology, which allows the assessment of the potential environmental impacts throughout the life cycle of a system. Once these adjustments made, this new methodology LCRA is explained and applied to two energy pathways (or life cycles): hydrogen (produced from the biomass) and gasoline pathways.

Metal finishing industries produce an important tonnage of metal hydroxide sludge (MHS) during the treatment of their liquid effluents charged with heavy metals. Generally, a small part of these sludge is valorized because of their important metal fickleness. Consequently, the majority of these metal hydroxide sludge is sent to landfill centers. We propose to valorize this sludge by using them as pollutant sorbent in order to retain the polluting species contained in the industrial aqueous effluents. The chosen pollutant for this preliminary study is Chromium (+VI). Starting from an experimental well defined protocol, various parameters have been studied (chemical nature of the sludge, solid/liquid ratio, concentration of the pollutant, particle size) in order to determine the experimental parameters which influence the sorption yield of these sludge and thus to validate the feasibility of an industrial application of this new way of valorisation. First results point out that the sorption yield is more than 95% independently from the experimental conditions. Moreover, experiments highlight that the sludge mass (and so sorbent sites) is THE only real parameter which influences the yield. In this article, a review of the patents on different aspects of the valorisation of polymetallic hydroxide sludge as pollutant trappers is presented.

Initie par l'Organisation des Nations Unies (UN-Water), le dernier rapport sur l'evaluation globale annuelle de l'assainissement et l'eau potable de l'Organisation mondiale de la sante (GLAAS, 2010) presente bien l'ampleur des enjeux de l'assainissement des eaux usees et leurs consequences sur la sante humaine. La resolution de l'Assemblee generale de Nations-Unies sur le droit de l'homme a l'eau et a l'assainissement (ONU A/RES/64/292, 2010) ainsi que celle, unanime, de la 65e assemblee mondiale de la Sante (WHA64.24, 2011) demontre la volonte des etats membres a vouloir ameliorer la situation et a soutenir l'effort mondial pour realiser l'assainissement durable . Afin de repondre a ces engagements et en particulier a celui de reduire de moitie la proportion des personnes qui n'ont pas acces a un assainissement d'ici 2015 (Cible 7C, NU 2008), la solution proposee emane d'un changement de paradigme dans la conception des stations d'epuration. Ce changement est fonde sur une modification de la finalite des stations d'epuration, a savoir : produire des biens consommables soumis a des normes de rejets. Il repose sur les principes de la qualite industrielle et d'une approche systemique regroupant ceux d'economie, d'ecologie, de thermodynamique ainsi que de sante et securite des populations. Les etudes ont porte sur differentes technologies de traitement des eaux usees (coagulation-floculation, biologique incluant les plantes et l'ozonation) ainsi que sur les technologies de valorisation energetiques des boues (compostage, methanisation et gazeification). Les donnees ont ete obtenues en realisant des tests en laboratoire ainsi que des essais sur site a l'aide d'unites de traitement a l'echelle pilote. Ces donnees associees a des resultats provenant des experiences publiees dans la litterature ont permis de realiser des calculs et des simulations pour valider les scenarios de traitement. Par exemple, les resultats des essais en usine ont permis de montrer qu'en derivant une fraction des eaux usees (33 % du debit) avant le traitement biologique, puis en desinfectant avec de l'ozone les deux effluents separement, la consommation d'ozone est reduite de 10 % pour atteindre le meme objectif de desinfection. En derivant ce pourcentage de debit d'eaux usees, les temps de retention du systeme de traitement biologique et de la decantation secondaire sont augmentes d'un pourcentage equivalent. Cette augmentation permet d'augmenter les rendements d'epuration des deux technologies, reduisant du meme coup la consommation d'ozone pour la desinfection. Les seconds resultats proviennent d'une etude de faisabilite visant a integrer un traitement biologique dans une station d'epuration physico-chimique afin d'ameliorer la qualite des effluents rejetes dans le milieu recepteur. Les resultats des simulations ont permis de mettre en evidence une reduction de la consommation annuelle de coagulants en concevant un systeme de traitement ou une partie des eaux usees sont traitees par une coagulation-floculation-decantation et le reste par un traitement biologique, avant d'etre rejetees dans le milieu recepteur. Finalement, les resultats de simulation de scenarios de traitement des eaux usees et de valorisation des boues produites ont permis de determiner les conditions pour qu'une station d'epuration soit autonome energetiquement. En combinant ces resultats, les principes de conception d'une station de traitement des eaux usees en reseau ont pu etre etablis.

1200 million ton of Polychlorinated biphenyls (PCBs) have been produced worldwide and about 400 million tons are considered to be spread in the Environment. PCBs are persistent pollutants and highly immunotoxic toxic and carcinogenic. They may concentrate in river sediments and strongly affect ecosystems and biodiversity. Conventional cleaning processes are environmental non-friendly methods and there is still need to look for alternative ways of treating these contaminations. Washing sediments with surfactant solutions offers good results. Layered Double Hydroxides (LDH) are synthetic anionic clays that have proved to be good adsorbant for both surfactant and organic pollutants. Modification of LDH by anionic surfactant or polymer enhances their adsorption properties toward hydrophobic xenobiotics. This study aims to develop a new cleaning process based on the adsorption of PCBs by organically modified LDH. 4-chlorobiphenyl (PCB 3) was used as a model. ZnRAl LDH materials with variable anion exchange capacities, intercalated by sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS) or humic acid were tested as new sorbents. PCB 3 adsorptions were processed either by intercalation or direct coprecipitation (scheme). Surfactant modified LDH show a great ability to trap PCB 3, about 97% adsorbed, all the same by coprecipitation with pollutant. Humic acid adsorbed LDH are less efficient, with a maximum of 50% of adsorption.

The systematic stratigraphy of the Pacific littoral of Costa Rica has been reorganized in three supergroups: 1. Papagayo: mafic and ultramafic oceanic basements and volcanicaIly or tectonically associated sediments. 2. Garza: oceanic sedimentary cover including pelagics (Sabana Grande Group) and slope deposits (Samara Group). 3. Mal Pais: neritic sedimentary cover, subdivided into 5 epochs. A major, upper Santonian tectonic event divides the geologic history into two phases: 1. The Nicoya Complex with its Bathonian/Callovian Santonian (BAUMGARTNER 1984) oceanic sedimentary cover and the Santa Elena Peridotite form together a nappe edifice with a southern vergence (BOURa15— et al. in press). 2. Since the Campanian, this structure is part of the stable isthmic crust, the substrate of the studied upper Senonian-Cenozoic sedimentary sequen ces, affected by open folding and normal faulting only. No accretionary struc-tures related to subduction along the Middle-American Trench, effective since ttat latest Senonian, have been observed. Ocean floor continued te form during the latest Senonian-early Paleocene in a primitive island arc environment (Que-pos, Osa). Campanian-middle Eocene pelagic (and background) sedimentation followed the paleooceanographic trends observed in the Pacific, amplified by local (equatorial, eastern ocean margin) high fertility. A shallow CCD is reflected by Santonian-lower Campanian and upper Paleocen-middle Eocene radiolarian-rich siliceous deposits. In the late Campanian-Maestrichtian a drastic drop of the CCD overruled subsidence and resulted in deposition of foraminifer-rich pelagic limestones. Thick Maestrichtian-Paleocene turbidite and mass flow sequences were deposited in YW-SE trending elongate basins and document the erosion of an emerged andesitic volcanic are, che product of active subduction, surrounded by narrow carbonate and silicic/astio shelves, set aboye steep, unstable slopes. A tectonic event at the middleilate ocene boundary caused mayor gravitative s/iding and slumping of the upper part of the oceanic sequence, subsequent uplift and a regional, unconformable onset of shallow carbonate deposition, while turbiditc sedimentation persisted in some arcas (Santa Elena, Quepos). An inferred thickened oceanic crust in isostatic equilibrium should form a sea floor at subphotie depths. However, tectonie uplift has repeatdly brought the substrate te shallow depth and allowed the deposition of unconformable, thin, shortlived, neritic sequences, forffied during five succesive epochs: Epoch 1. Campanian-Maestriehtian: The structurally highest parts of the upper Santonian orogen were uplifted te subaerial and shallow photic depths where rudis-tid limestones developed. Epoch 2. Paleocene-early Encone: Voleanic activity related tu subduction gave rise tu an island are surrounded by shallow platforms NE of the study area, only known from reworked carbonate elasts in slope deposits (Samara, Quepos). Epoch 3. Middle-late Eoeene: Tectonic uplift brought most of the area tu shallow photic depth which led tu the formation uf the widespread largor foramini-fer - red algal limestones. Epoch 4. Oligocene-early Miocene: Most of the central area was emerged and only near the trench (Nosara-Mal Pais) thin shallow clastic sequences developed, while turbidite basins persisted in the NW and SE (Dept. Rivas, Nicaragua, Fila Costena). Epoch 5. Late Miocene-Pleistocene: Littoral deposits are concentrated around the south of Nieoya, in areas of recent uplift (FISCHER 1980).