Tectonic and hydrodynamic control of landslides in the northern area of the Central Rif, Morocco   总被引：1，自引：0，他引：1  

Jamal El Khattabi  Erick Carlier   《Engineering Geology》2004,71(3-4):255-264

The northern edge of the Central Rif (Morocco) is subject to numerous landslides where mechanisms do not correspond to the classical models used by geomechanics specialists. It is necessary to adopt a multidisciplinary approach that combines geomorphology, geology, hydrogeology, and geotechnics in order to understand how such slope failures are generated, especially in a region with a heterogeneous structure characterised by significant lithological differences, severe fracturing, and thrust sheets where tectonic contacts play a major role in groundwater circulation. This report shows that these failures are essentially controlled by the tectonic contact separating the Tisirene and Chouamat thrust sheets and by subsurface hydrodynamic conditions. A model of spatial and temporal variations in the factor of safety is proposed.  相似文献   

Land uplift near Vatnajökull, Iceland, as observed by GPS in 1992, 1996 and 1999     

Lars E. Sjöberg  Ming Pan  Sigurdur Erlingsson  Erick Asenjo  Kolbeinn Arnason 《Geophysical Journal International》2004,159(3):943-948

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An adaptive finite element model for wellbore breakout simulation     

Diogo L. Cecílio  Philippe R. B. Devloo  Sônia M. Gomes  Erick S.R. Santos 《国际地质力学数值与分析法杂志》2019,43(4):814-828

A finite element formulation is proposed and implemented for analysing the stability of excavated wells using the DiMaggio-Sandler constitutive elastoplastic model with a typical carbonate reservoir configuration. The quality of the finite element approximation is ensured by applying smooth curved elements adapted to the wellbore geometry, and h − p adaptive finite element meshes in the plastic zone. General purpose procedures are defined to transfer the elastoplastic deformation history to newly created integration points. A breakout damage criterion is proposed based on the second invariant of the deviatoric plastic deformation tensor. This damage criterion is used to apply a mesh movement algorithm to represent material collapse. The automatic successive application of the breakout damage criterion results in elliptical realistically looking geometries obtained in experiments reported in the literature.  相似文献   

Projected changes in atmospheric river events in Arizona as simulated by global and regional climate models     

Erick R. Rivera  Francina Dominguez 《Climate Dynamics》2016,47(5-6):1673-1691

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Modelling of groundwater flow in heterogeneous porous media by finite element method     

Hassan Smaoui  Lahcen Zouhri  Abdellatif Ouahsine  Erick Carlier 《水文研究》2012,26(4):558-569

The HySuf‐FEM code (Hydrodynamic of Subsurface Flow by Finite Element Method) is proposed in this article in order to estimate the spatial variability of the transmissivity values of the Berrechid aquifer (Morocco). The calibration of the model is based on the hydraulic head, hydraulic conductivity and recharge. Three numerical tests are used to validate the model and verify its convergence. The first test case consists in using the steady analytical solution of the Poisson equation. In the second, the model has been compared with the hydrogeological system which is characterized by an unconfined monolayer (isotropic layer) and computed by using PMWIN‐MODFLOW software. The third test case is based on the comparison between the results of HySuf‐FEM and the multiple cell balance method in the aquifer system with natural boundaries case. Good agreement between the Hydrodynamic of Subsurface Flow, the numerical tests and the spatial distribution of the thickening of the hydrogeological system is deduced from the analysis and the interpretations of hydrogeological wells. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Food web structure of two Mediterranean lagoons under varying degree of eutrophication   总被引：2，自引：0，他引：2  

Antoine Carlier  Pascal Riera  Jean-Michel Amouroux  Jean-Yves Bodiou  Martin Desmalades  Antoine Grmare 《Journal of Sea Research》2008,60(4):264-275

The food web structure and functioning of two north-western Mediterranean lagoons exhibiting contrasting degrees of eutrophication and marine influences were compared through δ¹³C and δ¹⁵N analysis of major potential food sources and consumers. The Lapalme Lagoon is well preserved and has kept a natural and temporary connection with the open sea. Conversely, the Canet Lagoon is heavily eutrophicated and its water exchange with the open sea has been artificially reduced. In Lapalme, all potential food sources and consumers exhibited δ¹⁵N values indicative of pristine coastal areas. Suspended particulate organic matter (POM) and sediment organic matter (SOM) pools seemed to constitute the main food sources of most primary consumers. Both primary producers and all consumers were much more ¹⁵N-enriched (by  10‰) and more ¹³C-depleted in Canet than in Lapalme. This reflected: (1) the assimilation of important amounts of anthropogenic nitrogen in the food web, and (2) a marked and uniform influence of ¹³C-depleted allochtonous sources of carbon. Based on the mean δ¹⁵N of primary consumers, we found rather similar food web lengths in both lagoons with top consumers at trophic levels 3.6 and 4.0 in Canet and Lapalme, respectively. However, the eutrophication of the Canet Lagoon resulted in a simplification of the food web structure (i.e., a single trophic pathway from a ¹⁵N-enriched fraction of the SOM pool to top predators) compared to what was observed in Lapalme Lagoon where additional ¹³C-enriched food sources played a significant trophic role. Moreover, some consumers of Canet tended to exploit primary producers to a larger extent (and thus to exhibit lower trophic levels) than in Lapalme.  相似文献   

Simulation Chamber Studies of the Atmospheric Oxidation of 2-Methyl-3-Buten-2-ol: Reaction with Hydroxyl Radicals and Ozone Under a Variety of Conditions     

N. Carrasco  J. F. Doussin  M. O’Connor  J. C. Wenger  B. Picquet-Varrault  R. Durand-Jolibois  P. Carlier 《Journal of Atmospheric Chemistry》2007,56(1):33-55

This article presents a complete study of the diurnal chemical reactivity of the biogenic volatile organic compound (BVOC), 2-methyl-3-buten-2-ol (MBO) in the troposphere. Reactions of MBO with OH and with ozone were studied to analyse the respective parts of both processes in the global budget of MBO atmospheric reactivity. They were investigated under controlled conditions for pressure (atmospheric pressure) and temperature (298 ± 2 K) using three complementary European simulation chambers. Reaction with OH radicals was studied in the presence of and in the absence of NO _x . The kinetic study was carried out by relative rate study using isoprene as a reference. The rate constant found for this reaction was molecule⁻¹ cm³ s⁻¹. FTIR spectroscopy, DNPH- and PFBHA-derivatisation analyses were performed for reactions with both OH radicals and ozone. In both reactions, the hydroxycarbonyl compound, 2-hydroxy-2-methylpropanal (HMPr) was positively identified and quantified, with a yield of in the reaction with OH, and a yield of and 0.84 ± 0.08 in the reaction with ozone under dry (HR < 1%) and humid conditions (HR = 20%–30%). A primary production of two other carbonyl compounds, acetone , and formaldehyde was found in the case of the dry ozonolysis experiments. Under humid conditions, only formaldehyde was co-produced with HMPr as a primary carbonyl compound, with a yield of . For the reaction with OH, three other carbonyl compounds were detected, acetone , formaldehyde and glycolaldehyde . In addition some realistic photo-oxidation experiments were performed to understand in an overall way the transformations of MBO in the atmosphere. The realistic photo-oxidation experiments were conducted in the EUPHORE outdoor simulation chamber. It was found that this compound is a weak secondary aerosol producer (less than 1% of the carbon balance). But it was confirmed that it is a potentially significant source of acetone, Δ[Acetone]/Δ[MBO] = 0.45. With our experimental conditions ([MBO]₀ = 200 ppb, [NO]o = 50 ppb), an ozone yield of Δ[O₃]/Δ[MBO] = 1.05 was found.  相似文献   

Separation of rifting and lithospheric folding signatures in the NW-Alpine foreland   总被引：2，自引：0，他引：2  

O. Bourgeois  M. Ford  M. Diraison  C. Le Carlier de  Veslud  M. Gerbault  R. Pik  N. Ruby  S. Bonnet 《International Journal of Earth Sciences》2007,96(6):1003-1031

The development of the Alpine mountain belt has been governed by the convergence of the African and European plates since the Late Cretaceous. During the Cenozoic, this orogeny was accompanied with two major kinds of intraplate deformation in the NW-European foreland: (1) the European Cenozoic Rift System (ECRIS), a left-lateral transtensional wrench zone striking NNE-SSW between the western Mediterranean Sea and the Bohemian Massif; (2) long-wavelength lithospheric folds striking NE and located between the Alpine front and the North Sea. The present-day geometry of the European crust comprises the signatures of these two events superimposed on all preceding ones. In order to better define the processes and causes of each event, we identify and separate their respective geometrical signatures on depth maps of the pre-Mesozoic basement and of the Moho. We derive the respective timing of rifting and folding from sedimentary accumulation curves computed for selected locations of the Upper Rhine Graben. From this geometrical and chronological separation, we infer that the ECRIS developed mostly from 37 to 17 Ma, in response to north-directed impingement of Adria into the European plate. Lithospheric folds developed between 17 and 0 Ma, after the azimuth of relative displacement between Adria and Europe turned counter-clockwise to NW–SE. The geometry of these folds (wavelength = 270 km; amplitude = 1,500 m) is consistent with the geometry, as predicted by analogue and numerical models, of buckle folds produced by horizontal shortening of the whole lithosphere. The development of the folds resulted in ca. 1,000 m of rock uplift along the hinge lines of the anticlines (Burgundy–Swabian Jura and Normandy–Vogelsberg) and ca. 500 m of rock subsidence along the hinge line of the intervening syncline (Sologne–Franconian Basin). The grabens of the ECRIS were tilted by the development of the folds, and their rift-related sedimentary infill was reduced on anticlines, while sedimentary accumulation was enhanced in synclines. We interpret the occurrence of Miocene volcanic activity and of topographic highs, and the basement and Moho configurations in the Vosges–Black Forest area and in the Rhenish Massif as interference patterns between linear lithospheric anticlines and linear grabens, rather than as signatures of asthenospheric plumes.

O. BourgeoisEmail:

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A groundwater salinity hotspot and its connection to an intermittent stream identified by environmental tracers (Mt Lofty Ranges,South Australia)     

Thomas A. Anderson  Erick A. Bestland  Lesja Soloninka  Ilka Wallis  Edward W. Banks  Markus Pichler 《Hydrogeology Journal》2017,25(8):2435-2451

High and variable levels of salinity were investigated in an intermittent stream in a high-rainfall area (～800 mm/year) of the Mt. Lofty Ranges of South Australia. The groundwater system was found to have a local, upslope saline lens, referred to here as a groundwater salinity ‘hotspot’. Environmental tracer analyses (δ¹⁸O, δ²H, ^87/86Sr, and major elements) of water from the intermittent stream, a nearby permanent stream, shallow and deep groundwater, and soil-water/runoff demonstrate seasonal groundwater input of very saline composition into the intermittent stream. This input results in large salinity increases of the stream water because the winter wet-season stream flow decreases during spring in this Mediterranean climate. Furthermore, strontium and water isotope analyses demonstrate: (1) the upslope-saline-groundwater zone (hotspot) mixes with the dominant groundwater system, (2) the intermittent-stream water is a mixture of soil-water/runoff and the upslope saline groundwater, and (3) the upslope-saline-groundwater zone results from the flushing of unsaturated-zone salts from the thick clayey regolith and soil which overlie the metamorphosed shale bedrock. The preferred theory on the origin of the upslope-saline-groundwater hotspot is land clearing of native deep-rooted woodland, followed by flushing of accumulated salts from the unsaturated zone due to increased recharge. This cause of elevated groundwater and surface-water salinity, if correct, could be widespread in Mt. Lofty Ranges areas, as well as other climatically and geologically similar areas with comparable hydrogeologic conditions.  相似文献   

Recent Advances in Agent-Based Tsunami Evacuation Simulations: Case Studies in Indonesia,Thailand, Japan and Peru   总被引：1，自引：0，他引：1  

Erick Mas  Shunichi Koshimura  Fumihiko Imamura  Anawat Suppasri  Abdul Muhari  Bruno Adriano 《Pure and Applied Geophysics》2015,172(12):3409-3424

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