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Considerable advances in the development of user-friendly modeling code against the limitations of analytical methods have led to an increase in the utilization of numerical methods to predict the dynamic behavior of tunnel lining under seismic loading. This paper examines the seismic performance of the ZAM (Zaouit Ait Mellal) twin tunnels located between the cities of Marrakesh and Agadir in Morocco, using the Finite Difference Method (FDM) provided by FLAC 2D software, and Finite Element Method (FEM) provided by PLAXIS 2D software. The adopted simulated acceleration is obtained from an artificial earthquake event with free-field boundary conditions in the numerical models. Three points are chosen in the tunnel lining: two in the corner and one in the crown. The results show the evolution displacement during the dynamic time for each point, we note different distributions of values in FLAC compared with PLAXIS, which these differences are justified by the type of interface used in both programs.

49 pages, 15 figures, The seafloor of the Alboran Sea reflects its complex tectonic, sedimentary, and oceanography dynamics as a consequence of the geological context, involving interaction between the Eurasian and African plates, and oceanographic context, as it is where the Atlantic and Mediterranean waters meet. Their physiography has a semi-enclosed configuration characterized by two margins (the Spanish Iberian and North Africa—mostly Moroccan margins) enclosing deep basins. Tectonic activity is mainly attested by folds and faults that predominantly affect the central and eastern seafloor sectors, as well as numerous seamounts and fluid-flow features (pockmarks, mud volcanoes, and diapirs) that dot the seafloor. The sedimentary and oceanographic processes allow us to distinctly define two principal environments in the Alboran Sea: the shallow proximal margin (continental shelf); and the deep distal margin (continental slope and base of the slope) with the adjacent sub-basins. The shelf mostly comprises prodeltaic and infralittoral prograding wedges, with local bedform fields, submarine valleys, and wave-cut terraces. Coastal and fluvio-marine sedimentary processes, acting since the last glacial period, are responsible for these features. The deep marine environment is characterised by the ubiquity of contourites, whose continuity is interrupted by turbidite systems, canyons, and landslides. The alongslope action of the Mediterranean waters and their interfaces with the Atlantic water has been the main process governing transport, seafloor reworking, and sedimentation of contourites. Mass-movement processes are responsible for the formation of: (1) turbidite systems—turbidity flows and mass flows were dominant during the last glacial sea-level lowstand, evolving to dilute gravity flows during present interglacial high stand; and (2) landslides—the main triggering factors comprising over-steepening, seismicity, under consolidation due to overpressure by interstitial fluids, stratigraphy, and high sedimentation rates. Locally, still-undetermined biological activity in the Spanish and coral activity in the Moroccan margin generated fields of mounded bioconstructions. The seafloor morphology of the Alboran Sea offers interesting clues for assessing the main potential geological hazards, with tectonic seismicity and landslides (as well as their related tsunamis) being some of the most important potential hazards affecting coastal populations. In addition, the seafloor morphology in combination with assemblages of habitat-forming species enables habitat identification and mapping, This work was supported by the following Spanish projects INCRISIS, DAMAGE (CGL2016-80687-R AEI/FEDER), FAUCES (CTM2015-65461-C2-1-R) and ALSSOMAR S2S (CTM2017-88237-P), RNM 148 and RNM 328 groups of Junta de Andalucía, MONCARAL and RIGEL projects (Instituto Español de Oceanografía) Marboro cruises. Likewise, this study was supported by the French program Actions Marges and the EUROFLEETS program-SARAS cruise (FP7/2007-2013; 228344)

The crustal and mantle structure of the north-eastern part of Egypt and the surrounding area is shown by means of S-velocity maps for depths ranging from zero to 45 km, determined by the regionalization and inversion of Rayleigh-wave dispersion. This analysis shows several types of crust with an average S-velocity ranging from 2.5 to 3.9 km/s. The values of S-velocity range from 2.5 km/s at the surface to 3.4 km/s at 10 km depth for the Sinai Peninsula, Gulf of Aqaba, Gulf of Suez, Red Sea, Dead Sea, western part of Dead sea and Arabian Plate. In the lower crust, the values of the S-velocity reach 4.0 km/s. In the uppermost mantle, the S-velocities range from 4.4 to 4.7 km/s. The crustal thickness ranges from the oceanic thin crust (around 15–20 km of thickness), for Red Sea and the extended continental margins, to 35–45 km of thickness for the Arabian plate. A gradual increasing crustal thickness is observed from north-east to south-west. While the Moho is located at 30–35 km of depth under the Sinai Peninsula, Gulf of Aqaba, Dead Sea Fault (DSF) and Dead Sea, a thinner crust (20–25 km of thickness) is found at the east of DSF and under the northern and the southern part of the Gulf of Suez. The crustal thickness varies within Sinai from the southern edge to the north, which provided an evidence for the presence of an Early Mesozoic passive margin with thinned continental crust in the north of Sinai. The change of crustal structure between the Gulf of Aqaba and the Gulf of Suez is due to the different tectonic and geodynamic processes affecting Sinai. In general, our results are consistent with surface geology and the Moho depth inferred from reflection and refraction data, receiver function, surface-wave analysis and P-S tomography. The strong variations in the base of the Moho reflect the complex evolution of the African and Arabian plate boundary region.

Remote sensing techniques based on medium resolution satellite imagery are being widely applied for mapping plastic covered greenhouses (PCG). This article aims at testing the spectral consistency of surface reflectance values of Sentinel-2 MSI (S2 L2A) and Landsat 8 OLI (L8 L2 and the pansharpened and atmospherically corrected product from L1T product; L8 PANSH) data in PCG areas located in Spain, Morocco, Italy and Turkey. The six corresponding bands of S2 and L8, together with the normalized difference vegetation index (NDVI), were generated through an OBIA approach for each PCG study site. The coefficient of determination (r2) and the root mean square error (RMSE) were computed in sixteen cloud-free simultaneously acquired image pairs from the four study sites to evaluate the coherence between the two sensors. It was found that the S2 and L8 correlation (r2 > 0.840, RMSE < 9.917%) was quite good in most bands and NDVI. However, the correlation of the two sensors fluctuated between study sites, showing occasional sun glint effects on PCG roofs related to the sensor orbit and sun position. Moreover, higher surface reflectance discrepancies between L8 L2 and L8 PANSH data, mainly in the visible bands, were always observed in areas with high-level aerosol values derived from the aerosol quality band included in the L8 L2 product (SR aerosol). In this way, the consistency between L8 PANSH and S2 L2A was improved mainly in high-level aerosol areas according to the SR aerosol band.

The final publication is available at Springer via http://dx.doi.org/10.1007/s10518-019-00643-y The purpose of this study is to seismically evaluate reinforced concrete buildings in the northern region of Morocco. In the past, the area have suffered from numerous earthquakes, lately the 2004 earthquake near the city of Al Hoceima (Mw of 6.4 causing more than 600 fatalities) and the region is constantly subject to seismic threats. A total number of 2746 residential buildings from the cities of Al Hoceima and Imzouren have been investigated for the purposes of this study. The proposed method adapts the Japanese Seismic Index Method making it more time-efficient and tuned to the context of the Moroccan construction. The method is based on a visual inspection of buildings and an in-depth insight of how constructions are designed and built in the region. The results show that Imzouren is more exposed to damage than the city of Al Hoceima is, mainly due to the soil nature. The method also shows that as the building’s height increases, it becomes more vulnerable. Furthermore, constructions that comply with the seismic regulations have a significant capacity to withstand damage without collapsing unlike other non-engineered buildings that have an almost non-existent ductility and can collapse soon during intense earthquakes.

The final publication is available at Springer via http://dx.doi.org/10.1007/s11069-016-2566-8 Al Hoceima is one of the most seismic active regions in north of Morocco. It is demonstrated by the large seismic episodes reported in seismic catalogs and research studies. However, seismic risk is relatively high due to vulnerable buildings that are either old or don’t respect seismic standards. Our aim is to present a study about seismic risk and seismic scenarios for the city of Al Hoceima. The seismic vulnerability of the existing residential buildings was evaluated using the vulnerability index method (Risk-UE). It was chosen to be adapted and applied to the Moroccan constructions for its practicality and simple methodology. A visual inspection of 1102 buildings was carried out to assess the vulnerability factors. As for seismic hazard, it was evaluated in terms of macroseismic intensity for two scenarios (a deterministic and probabilistic scenario). The maps of seismic risk are represented by direct damage on buildings, damage to population and economic cost. According to the results, the main vulnerability index of the city is equal to 0.49 and the seismic risk is estimated as Slight (main damage grade equal to 0.9 for the deterministic scenario and 0.7 for the probabilistic scenario). However, Moderate to heavy damage is expected in areas located in the newer extensions, in both the east and west of the city. Important economic losses and damage to the population are expected in these areas as well. The maps elaborated can be a potential guide to the decision making in the field of seismic risk prevention and mitigation strategies in Al Hoceima.

Concrete is the most commonly used material in civil engineering, given its economic cost and ease of manufacture. Its strength depends on the characteristics of its constituents. A good mix makes it possible to build solid, durable and economical structures. The present work aims to characterize the gravel of the Eastern region (quarry of eastern Morocco) by granulometric analysis and water absorption. Then, the studied gravel is used to produce three types of concrete (B20, B25 and B30), which were assessed in terms of water absorption and compressive strength. The last step is to study the effect of an adjuvant, more specifically a water reducer, on mechanical characteristics of local concrete. B25 concrete was chosen for the last step since it is the most used type in the region. Results show that adding a water reducer adjuvant, in this case 'Chrysoplast', can improve the compressive strength of concrete if the percentage added is accurately determined.

The main purpose of this study is to assess seismic risk and present earthquake loss scenarios for the city of Imzouren, in northern Morocco. An empirical approach was chosen to assess the seismic vulnerability of the existing buildings, using the Vulnerability Index Method (RISK-UE), and considering two earthquake scenarios (deterministic and probabilistic). Special concern was given to the seismic vulnerability in Imzouren since the 2004 earthquake (24 February, mw = 6.4) that struck the region and caused substantial damage. A site investigation was conducted in the city targeting more than 3000 residential buildings, which had been closely examined and catalogued to assess their seismic vulnerability. The results of the seismic risk assessment in the city are represented through damage to the buildings, harm to the population and economic loss. Generally, the results obtained from the deterministic approach are in agreement with the damage caused by the 2004 earthquake.

Galindo-Zaldívar, Jesús ... et al.-- 18 pages, 10 figures, The Eurasian-African NW-SE oblique plate convergence produces shortening and orthogonal extension in the Alboran Sea Basin (westernmost Mediterranean), located between the Betic and Rif Cordilleras. A NNE-SSW broadband of deformation and seismicity affects the Alboran central part. After the 1993–1994 and 2004 seismic series, an earthquake sequence struck mainly its southern sector in 2016–2017 (main event M = 6.3, 25 January 2016). The near-surface deformation is investigated using seismic profiles, multibeam bathymetry, gravity and seismicity data. Epicenters can be grouped into two main alignments. The northern WSW-ENE alignment has reverse earthquake focal mechanisms, and in its epicentral region recent mass transport deposits occur. The southern alignment consists of a NNE-SSW vertical sinistral deformation zone, with early epicenters of higher-magnitude earthquakes located along a narrow band 5 to 10-km offset westward of the Al Idrisi Fault. Here near-surface deformation includes active NW-SE vertical and normal faults, unmapped until now. Later, epicenters spread eastward, reaching the Al Idrisi Fault, characterized by discontinuous active NNE-SSW vertical fractures. Seismicity and tectonic structures suggest a westward propagation of deformation and the growth at depth of incipient faults, comprising a NNE-SSW sinistral fault zone in depth that is connected upward with NW-SE vertical and normal faults. This recent fault zone is segmented and responsible for the seismicity in 1993–1994 in the coastal area, in 2004 onshore, and in 2016–2017 offshore. Insights for seismic hazard assessment point to the growth of recent faults that could produce potentially higher magnitude earthquakes than the already formed faults, This study was supported by the Spanish projects INCRISIS, DAMAGE (CGL2016‐80687‐R AEI/FEDER) and FAUCES (CTM2015‐65461‐C2‐1‐R), RNM 148 ‐ Junta de Andalucía, and Marlboro cruises. French program Actions Marges, the EUROFLEETS program‐SARAS cruise (FP7/2007‐2013; 228344). The participation of D. Palomino and J. T. Vazquez was funded by the IEO project RIGEL

The southern Gibraltar Arc’s bloc (Rif’s belt) has a complex geological setting including peridotites outcropping in the Rif and Betic. They are among the largest infracontinental mantle rock outcrops worldwide. In spite of several geological studies, the deep structure of this area remains poorly defined. The aim of this work is giving a reliable geometry of the major geological structures of the Rif, especially the peridotite bodies and faults or geological contacts. The results obtained from a multiscale analysis of geological contacts applied to gravity and aeromagnetic data were used to generate a structural map of the studied area. This method in association with the Euler method allowed estimating the strike direction, shape, dip, and depth of contacts. The map gives a model of the region and confirms the existence of several faults, localized or inferred, from former geological studies. This study suggests a large extension of the Beni Bousera peridotites on the offshore from Jebha to Ceuta, and highlights an extended anomaly related to deeper crops probably ophiolite remnant of the suture zone.

Sharp linear gradients in maps of potential field data are generally assumed to result from sharp discontinuities or boundaries between rocks having different densities or magnetic susceptibilities and are usually associated with faults or other geological contacts. The computation of the horizontal gradients of the gravity field permits us to localize the limits of such blocks and then the fault locations. The horizontal derivative maxima of the Bouguer anomaly and its upward continuation at several heights show lineaments that could reflect the layout of faults and/or contacts and their dip directions. The application of this method to the Bouguer anomaly map of Morocco (with 19,571 points, using an average crustal density ρ = 2.67 g/cm 3 ) allowed us to perform a multiscale analysis of the gravimetric lineaments of the country. The obtained structural map is consistent with several faults already identified in previous studies, and highlights five new major subsurface faults systems with location and dip: the Saghro fault system; Bou-Arfa Midelt fault system; Sidi Slimane Mezquitem fault; Ksar El Kebir–Chefchaouen fault and the Rifan West Mediterranean fault. In addition, this study suggests a new shape and localization for the Agadir-Oujda trans-Moroccan major fault with a NE-SW direction and 900 km length, subdividing Morocco into two main domains. The results of this study contribute to the improvement of the regional structural map of the north western part of Africa, which is situated within the convergence zone between Africa and Eurasia.

The uppermost 50 km of the lithospheric structure of the northern part of the Iberian Peninsula is presented in this study, by means of a set of 2D images of shear-wave velocity for depths raging from 0 to 50 km. This goal will be attained by means of the inversion of the Rayleigh-wave dispersion. For this purpose, the 23 earthquakes occurred on the vicinity of the study area, from 2001 to 2003, will be considered. The dispersion curves of these earthquakes have been measured for periods from 2 to 45 s, by combination of two digital-filtering techniques: Multiple Filter Technique (MFT) and Time Variable Filtering (TVF). The resulting set of source-station averaged dispersion curves has been inverted according to the generalized inversion theory, to get S-wave velocity models for each source-station path. Finally, these models have been interpolated by kriging to obtain a 2D mapping of the S-wave velocity structure, for the northern part of Iberia. The results presented in this paper show that the crust of the study area consisted of three main layers of varying thickness with a clear S-velocity contrast, resulting in a Moho depth of 30 km that decreases to 25 km in the eastern border of the Iberian peninsula and to 20 km in the Valencia trough. The upper crust has a sedimentary cover of 2 km thick. This upper crust has a thickness of 8 km, showing a very small lateral variation. In the middle crust (from 10 to 20 km depth), the S-velocity increases from 3.4 km/s to 3.7 km/s for the whole study area except for the east and the Valencia trough, where the S-velocities reach values of 3.9 km/s. The lower crust (from 20 to 30 km depth), exhibits S-velocities of 3.8–3.9 km/s, which jump to 4.3–4.7 km/s in the upper mantle.

In this study, we present the lithospheric structure of the south-eastern part of the Iberian Peninsula by means of a set of 2D images of shear velocity, for depths ranging from 0 to 50 km. This goal will be attained by means of the inversion of the Rayleigh wave dispersion. For it, the traces of 25 earthquakes occurred on the neighbouring of the study area, from 2001 to 2003, will be considered. These earthquakes have been registered by 11 broadband stations located on Iberia. All seismic events have been grouped in source zones to get an average dispersion curve for each source-station path. The dispersion curves have been measured for periods between 2 and 45 s, by combination of two digital filtering techniques: Multiple Filter Technique and Time Variable Filtering. The resulting set of source-station averaged dispersion curves has been inverted according to the generalized inversion theory, to get S-wave velocity models for each source-station path. Later, these models have been interpolated using the method of kriging, to obtain a 2D mapping of the S-wave velocity structure for the south-eastern part of Iberia. The results presented in this paper show that the techniques used here are a powerful tool to investigate the crust and upper mantle structure, through the dispersion analysis and its inversion to obtain shear velocity distributions with depth. By means of this analysis, principal structural features of the south-eastern part of Iberia, such as the existence of lateral and vertical heterogeneity in the whole study area, or the location of the Moho discontinuity at 30 km of depth (with an average S-velocity of uppermost mantle of 4.7 km/s), have been revealed. Other important structural features revealed by this analysis have been that the uppermost of Iberian massif shows higher velocity values than the uppermost of the Alpine domain, indicating that the massif is old and tectonically stable. The average velocity of the crust in Betic cordillera is of 3.5 km/s, while in the Iberian massif is 3.7 km/s. All these features are in agreement with the geology and other previous geophysical studies.

Introduction Presacral schwannomas are rare benign tumors, representing 1% to 5% of all schwannomas. We report a case diagnosed by imaging modalities (CT-MRI) and treated by complete surgical resection.

The orthometric heights can be obtained without levelling by means of the ellipsoidal and geoidal heights. For engineering purposes, these orthometric heights must be determined with high accuracy. For this reason, the determination of a high-resolution geoid is necessary. In Andalusia (South Spain) a new geopotential model (EIGEN-GL04C) has been available since the publication of a more recent regional geoid. As a consequence, these new data bring about improvements that ought to be included in a new regional geoid of Andalusia. With this aim in mind, a new gravimetric geoid determination has been carried out, in which these new data have been included. Thus, a new geoid is provided as a data grid distributed for the South Spain area from 36 to 39 degrees of latitude and –7 to –1 degrees of longitude (extending to 3 × 6 degrees), in a 120 × 240 regular grid with a mesh size of 1.5’ × 1.5’ and 28800 points in the GRS80 reference system. This calculated geoid and previous geoids are compared to the geoid undulations obtained for 262 GPS/levelling points, distributed within the study area. The new geoid shows an improvement in accuracy and reliability, fitting the geoidal heights determined for these GPS-levelling points better than any previous geoid.

In this paper, we perform a comprehensive explanation of the geophysical inversion of gravity data, as well as, how it can be used to determine the Moho undulation and the crustal structure. This inversion problem and the necessary assumptions to solve it will be described in this paper joint to the methodology used to invert gravity data (gravity anomalies). In addition, the application of this method to the determination of the Moho undulation will be performed computing the Moho undulation in the Moroccan area, as an example. Before the inversion, it is necessary the removing of the gravity effects for shallow and very deep structures, to obtain the deep gravity anomaly field that is associated to the deep structure and Moho undulation. These effects will be removed by a filtering process of the gravity anomaly field and by subtraction of the gravity anomalies corresponding to the very deep structure. The results presented in this paper will show that the inversion of gravity data is a powerful tool, to research the structure of the crust and the upper mantle. By means of this inversion process, the principal structural features beneath of Morocco area will be revealed.

Colorectal carcinoma during pregnancy is very rare. Prognosis is severe because of the advanced stage due to delay in diagnosis and the aggressiveness of this widespread metastatic disease. We present two cases of colorectal cancers, discovered during pregnancy, as well as the results of a literature review to apprehend this clinical situation, and we describe recommended medical and surgical management.

Objectifs Dans ce travail, les auteurs presentent leur experience de cancer de la tete du pancreas, vu aux urgences, a propos de 85 cas colliges au service des urgences chirurgicales viscerales, durant une periode de six ans (2000–2006).

But de l’etude Cette etude retrospective avait pour but de rapporter une serie de kystes hydatiques (KH) rompus dans les voies biliaires, operes dans le service de chirurgie generale a l’hopital militaire de Rabat, Maroc.

The lithospheric structure of the western part of the Mediterranean Sea is shown by means of S-velocity maps, for depths ranging from 0 to 35 km, determined from Rayleigh-wave analysis. The traces of 55 earthquakes, which occurred from 2001 to 2003 in and around the study area have been used to obtain Rayleigh-wave dispersion. These earthquakes were registered by 10 broadband stations located on Iberia and the Balearic Islands. The dispersion curves were obtained for periods between 1 and 45 s, by digital filtering with a combination of MFT and TVF filtering techniques. After that, all seismic events were grouped in source zones to obtain a dispersion curve for each source-station path. These dispersion curves were regionalized and after inverted according to the generalized inversion theory, to obtain shear-wave velocity models for rectangular blocks with a size of 1° × 1°. The shear velocity structure obtained through this procedure is shown in the S-velocity maps plotted for several depths. These maps show the existence of lateral and vertical heterogeneity. In these maps is possible to distinguish several types of crust with an average S-wave velocity ranging from 2.6 to 3.9 km/s. The South Balearic Basin (SBB) is more characteristic of oceanic crust than the rest of the western Mediterranean region, as it is demonstrated by the crustal thickness. We also find a similar S-wave velocity (ranging from 2.6 km/s at the surface to 3.2 km/s at 10 km depth) for the Iberian Peninsula coast to Ibiza Island, the North Balearic Basin (NBB) and Mallorca Island. In the lower crust, the shear velocity reaches a value of 3.9 km/s. The base of the Moho is estimated from 15 to 20 km under Iberian Peninsula coast to Ibiza Island, continues towards NBB and increases to 20–25 km beneath Mallorca Island. While, the SBB is characterized by a thinner crust that ranges from 10 to 15 km, and a faster velocity. A gradual increase in velocity from the north to the south (especially in the upper 25 km) is obtained for the western part of the Mediterranean Sea. The base of the crust has a shear-wave velocity value around of 3.9 km/s for the western Mediterranean Sea area. This area is characterized by a thin crust in comparison with the crustal thickness of the eastern Mediterranean Sea area. This thin crust is related with the distensive tectonics that exists in this area. The low S-wave velocities obtained in the upper mantle might be an indication of a serpentinized mantle. The obtained results agree well with the geology and other geophysical results previously obtained. The shear velocity generally increases with depth for all paths analyzed in the study area.

Duodenal tuberculosis is a rare clinical entity. The authors report and emphasize the lack of special clinical, radiological and endoscopic signs of duodenal tuberculosis. The diagnosis is affirmed, at laparotomy, out of the findings of peritoneal granulations or histology of lymphatic nodes. We report our experience of two cases of duodenal tuberculosis presenting with proximal intestinal obstruction and review the available literature.

A new gravimetric geoid is computed for South Spain and the Gibraltar Strait area. This geoid is located just in the junction between two tectonic plates (Euro-Asiatic and African plates) and in the junction of two gravimetric geoids: IGG2005 (the Iberian Gravimetric Geoid obtained in 2005) and MORGEO (the MORoccan GEOid). IGG2005 is the Iberian geoid and MORGEO is the Moroccan geoid, both geoids have been previously obtained. The new geoid is the gravimetric geoid solution that connects the two above-mentioned geoids, getting a more accurate and reliable picture of this area than the other previous geoids. The method used is the Stokes integral in convolution form, which shows to be an efficient method to reach the proposed objective. The terrain correction and the indirect effect have been taken into account. The new geoid is obtained as a regular grid (with a mesh size of 1.5′ × 1.5′) in the GRS80 reference system, covering the study area from 34° to 40° of latitude and from −8° to 0° of longitude. This gravimetric geoid and the previous geoids: IGG2005 and MORGEO; are compared to the geoid undulations derived at the validation points located on the study area (four GPS/levelling points measured on Morocco and five points of the European vertical reference network (EUVN) measured on Iberia). As it is expected, the new geoid is a more precise and reliable model, fitting the geoidal heights of these validation points with more accuracy than the other previous geoids. This new model will be useful for orthometric height determination by GPS in the mountains and remote areas, where levelling has many logistic problems. Also, it can be interesting for other geophysical purposes different to the height measurements, because it can provide a constraint for the density distribution, the thermal state of Lithosphere and the viscosity in the mantle. Such details can be inferred from a geoid model and the seismic velocity structure.

A quantitative assessment of forest cover change in the Moulouya River watershed (Morocco) was carried out by means of an innovative approach from atmospherically corrected reflectance Landsat images corresponding to 1984 (Landsat 5 Thematic Mapper) and 2013 (Landsat 8 Operational Land Imager). An object-based image analysis (OBIA) was undertaken to classify segmented objects as forested or non-forested within the 2013 Landsat orthomosaic. A Random Forest classifier was applied to a set of training data based on a features vector composed of different types of object features such as vegetation indices, mean spectral values and pixel-based fractional cover derived from probabilistic spectral mixture analysis). The very high spatial resolution image data of Google Earth 2013 were employed to train/validate the Random Forest classifier, ranking the NDVI vegetation index and the corresponding pixel-based percentages of photosynthetic vegetation and bare soil as the most statistically significant object features to extract forested and non-forested areas. Regarding classification accuracy, an overall accuracy of 92.34% was achieved. The previously developed classification scheme was applied to the 1984 Landsat data to extract the forest cover change between 1984 and 2013, showing a slight net increase of 5.3% (ca. 8800 ha) in forested areas for the whole region.

A homogeneous and reliable earthquake catalog is highly desirable in seismic hazard studies. This work, the compilation of as complete and homogeneous a main Moroccan earthquake catalog as possible, has been developed in the context of a project to compute the probabilistic seismic hazard in this region. The result shown here is the outcome of fruitful teamwork among several Spanish, Moroccan, and Algerian institutions. Previous earthquake catalogs that specifically cover this region ( e.g. Tadili and Ramdani 1983; Cherkaoui 1986; Benouar 1994), although employed in seismic hazard assessments (Benouar et al. 1996; Jimenez et al. 1999), did not span the desirable time interval. Many of them did not include pre-1900 events, i.e. , large shocks that occurred in the historical period. Moreover, a real magnitude unification process was not performed. Our initial goal was to catalog all known events from every available published source for the area between 27° to 37°N and 15°W to 1°E, including the southernmost part of Spain and Portugal and the western region of Algeria. We obtained a uniform catalog, using for this purpose several empirical relationships among reported magnitudes, macroseismic intensity, and moment magnitude. Finally, we removed all dependent events, as well as earthquakes with magnitudes smaller than M W 3.0. The final catalog covers the period from 1045 to 2005 and includes 1,739 mainshocks. It can be downloaded in a self-explanatory Excel file from the University of Jaen Web site at http://www.ujaen.es/investiga/rnm217/moroccan_catalog.xls. Tabulated data include agency, origin time, epicenter (coordinates, depth, and location), reported magnitude or maximum intensity and unified magnitude. The analyzed region (figure 1) includes the southernmost part of the Iberian Peninsula, the western portion of the Mediterranean Sea (Alboran Sea), the central-eastern area of the Atlantic Ocean, and the northwestern area of Africa (basically Morocco), located in the …

The lithospheric structure of the Sinai Peninsula is shown by means of nine shear velocity profiles for depths ranging from zero to 50 km, determined from the Rayleigh wave analysis. The traces of 30 earthquakes, which occurred from 1992 to 1999 in and around the study area, have been used to obtain Rayleigh wave dispersion. These earthquakes were registered by a broadband station located in Egypt (KEG station). The dispersion curves were obtained for periods between 3 and 40 s, by digital filtering with a combination of MFT and TVF filtering techniques. After that, all seismic events were grouped in source zones to obtain a dispersion curve for each source-station path. These dispersion curves were inverted according to generalized inversion theory, to obtain shear wave velocity models for each source-station path, which is the main goal of this study. The shear velocity structure obtained for the Sinai Peninsula is shown through the shear velocity distributions with depth. These results agree well with the geology and other geophysical results, previously obtained from seismic and gravity data. The obtained velocity models suggest the existence of lateral and vertical heterogeneity. The shear velocity increases generally with depth for all paths analyzed in the study area. Nevertheless, in some paths a small low velocity channel in the upper or lower crust occurs. Along these profiles, it is found that the crustal structure of the Sinai Peninsula consists of three principal layers: upper crust with a sedimentary layer and lower crust. The upper crust has a sedimentary cover of 2 km thick with an average S-velocity of 2.53 km/s. This upper crust has a variable thickness ranging from 12 to 18 km, with S-wave velocity ranging from 3.24 to 3.69 km/s. The Moho discontinuity is located at a depth of 30 km, which is reflected by a sharp increase in the S-velocity values that jump from 3.70–4.12 to 4.33–4.61 km/s.

In spite of the difficulty to obtain data for the African continent, the necessary measurements for the determination of a high-resolution geoid for Morocco have been collected. In Morocco, since the publication of most recent geoid (MGG97) a new geopotential model is available (EIGEN-CG01C, released on October 29, 2004) and a new high-resolution digital terrain model (SRTM 90M obtained from the Shuttle Radar Topography Mission), has been developed for the whole earth. Logically, these new data represent improvements that must be included in a new geoid for Morocco. For this reason, a new gravimetric geoid determination has been carried out including these new data. The method used in the computation of the geoid has been the Stokes integral in convolution form, because it is an efficient method to reach the proposal objective. The terrain correction has been applied to the gridded gravity anomalies, to obtain the corresponding reduced anomalies. The indirect effect has been also taken to account. Thus, a new geoid is provided as grid data distributed for Morocco from 27� to 37� of latitude and � 14� to 0� of longitude (extending 10 · 14� ), on a 401 · 561 regular grid with a mesh size of 1.5 0 · 1.5 0 and 224961 points in the GRS80 reference system. This calculated geoid and previous geoids existing for this study area (MGG97 and EIGEN-CG01C), are compared to the geoid undulations corresponding to 6 GPS/levelling points on Morocco. The new geoid shows an improvement in precision and reliability, fitting the geoidal heights of these GPS/levelling points with more accuracy than the other previous geoids. � 2007 Elsevier Ltd. All rights reserved.

SUMMARY It is well known that orthometric heights can be obtained without levelling by using ellipsoidal and geoidal heights. For engineering purposes, these orthometric heights must be determined with high accuracy. For this reason, the determination of a high-resolution geoid is necessary. In Iberia, since the publication of the most recent geoid (IBERGEO95), a new geopotential model has become available (EIGEN-CG01C, released on 2004 October 29) and a new high-resolution digital terrain model (SRTM 90M obtained from the Shuttle Radar Topography Mission) has been developed for the Earth. Logically, these new data represent improvements that must be included in a new geoid of Iberia. With this goal in mind, we have carried out a new gravimetric geoid determination in which these new data are included. The computation of the geoid uses the Stokes integral in convolution form, which has been shown as an efficient method to reach the proposed objective. The terrain correction has been applied to the gridded gravity anomalies to obtain the corresponding reduced anomalies. The indirect effect has also been taken into account. Thus, a new geoid is provided as grid data distributed for Iberia from 35° to 44° latitude and –10° to 4° longitude (extending to 9°× 14°) in a 361 × 561 regular grid with a mesh size of 1.5′× 1.5′ and 202 521 points in the GRS80 reference system. This calculated geoid and previous geoids that exist for this study area (IBERGEO95, EGM96, EGG97 and EIGEN-CG01C) are compared to the geoid undulations corresponding to 16 points of the European Vertical Reference Network (EUVN) on Iberia. The new geoid shows an improvement in precision and reliability, fitting the geoidal heights of these EUVN points with more accuracy than the other previous geoids.

A detailed dispersion analysis of Rayleigh waves generated by local earthquakes and occasionally by blasts that occurred in southern Spain, was undertaken to obtain the shear-wave velocity structure of the region at shallow depth. Our database includes seismograms generated by 35 seismic events that were recorded by 15 single-component short-period stations from 1990 to 1995. All these events have focal depths less than 10 km and body-wave magnitudes between 3.0 and 4.0, and they were all recorded at distances between 40 and 300 km from the epicentre. We analysed a total of 90 source-station Rayleigh-wave paths. The collected data were processed by standard digital filtering techniques to obtain Rayleigh-wave group-velocity dispersion measurements. The path-averaged group velocities vary from 1.12 to 2.25 km/s within the 1.0-6.0 s period interval. Then, using a stochastic inversion approach we obtained 1-D shear-wave velocity–depth models across the study area, which were resolved to a depth of circa 5 km. The inverted shear-wave velocities range approximately between 1.0 and 3.8 km/s with a standard deviation range of 0.05–0.16 km/s, and show significant variations from region to region. These results were combined to produce 3-D images via volumetric modelling and data visualization. We present images that show different shear velocity patterns for the Betic Cordillera. Looking at the velocity distribution at various depths and at vertical sections, we discuss of the study area in terms of subsurface structure and S-wave velocity distribution (low velocity channels, basement depth, etc.) at very shallow depths (0–5 km). Our results characterize the region sufficiently and lead to a correlation of shear-wave velocity with the different geological units features.

We have determined the three-dimensional P-wave velocity structure of the crust and uppermost mantle beneath the Iberia-Africa collision zone using local earthquake tomography. We have inverted arrival times of first-arriving P phases listed in the bulletins of the Instituto Geográfico Nacional and phases picked by us on permanent stations of other regional networks and on temporary broadband stations deployed in the frame of the TOPO-IBERIA project. In total we have used 38,624 P-wave arrival times from 2362 local events recorded at 120 seismic stations. The most remarkable result is the imaging of a large high velocity body following approximately the western Alboran coastline, with a horizontal dimension of at least 200. km and extending in depth from the surface down to 24. km. This body, not imaged previously with this extent using seismic tomography, coincides with surface exposures of subcontinental mantle (peridotites) in Iberia and Africa and with a belt of positive gravity anomalies. We have also found a marked contrast in the seismic velocities of the middle and lower crust of the Alboran basin, coinciding with the location of the Trans-Alboran Shear Zone. We attribute this contrast to widespread magmatic intrusions in the eastern part of the basin, resulting in higher P-wave velocities than in the west. This contrast would also explain the different orientation of the Trans-Alboran Shear zone with respect to the surface features and faults in the Alboran basin. We also image thick crust beneath the Betics and Rif, accompanied by downgoing lithosphere of the Iberian foreland and Gulf of Cadiz beneath the Betic-Rif-Alboran system., This is a contribution of the Team Consolider-Ingenio 2010 TOPO-IBERIA (CSD2006-00041).Additional funding was provided by the SIBERIA (CGL2006-01171), RIFSIS (CGL2009-09727) and ALERTES-RIM (CGL2013-45724-C3-3-R) projects

Les localisations gastro-intestinales de la tuberculose representent environ 1% des cas de tuberculose extrapulmonaire, et les localisations anoperineales sont sporadiques dans la litterature.

A dispersion analysis of Rg waves generated by local earthquakes surrounding the Alboran Sea (Western Mediterranean) has been undertaken to obtain its shear-wave velocity structure at shallow depths. We have used single-component short-period stations belonging to the Regional Seismic Network of Andalucia and the Spanish National Seismic Network. Our database includes seismograms generated by 18 earthquakes that occurred in the area during the period of 1992–95. The seismic events, with magnitudes between 2.9 and 4.9 and focal depths ranging from 2.7 to 12 km, were recorded at 13 stations at distances between 91 and 245 km from the source. We have analysed a total of 20 source-station Rg-wave paths. These seismic trajectories across the Alboran Sea provide irregular path coverage due to their geographical location. Despite sparse sampling the data collected have been processed with the help of digital filtering and group velocity dispersion curves have been obtained. The path group velocities vary from 1.21 to 1.91 km s −1 within the 1.7–5.8 s period interval. Then using a generalised inversion approach we have obtained 1D shear-wave velocity models for all source-station paths. Inversion for shear velocity structure gives velocity profiles down to a depth of 5 km. The shear-wave velocities range between 0.7 and 3.2 km s −1 within the standard deviation band of 0.05–0.17 km s −1 , and show significant variations from each other in the region of the Alboran Basin. We have applied an imaging technique aimed at volumetric modelling and data visualisation and we hereby present the tomographic results based on ray-path seismic velocities that were obtained for the basin. We have got an overall view of the sedimentary cover of the area regarding its geometry and S-wave velocity structure at very shallow depths (0–5 km). Although the relationship between lateral change in Rg dispersion and geologic structure may not be straightforward, we have observed a good correlation between those changes and surface geology.

Nous rapportons l’observation d’une tumeur papillaire solide de la tete du pancreas decouverte a l’occasion des douleurs abdominales chez une femme de 27 ans. Les caracteristiques echographiques et scannographiques de la lesion ne permettaient pas d’assurer un diagnostic etiologique de certitude. Le pronostic est bien meilleur que celui des autres tumeurs pancreatiques. Le traitement est exclusivement chirurgical.

La decouverte d’un diverticule du colon droit est une entite pathologique rare. La diverticulite en est souvent revelatrice, mais le diagnostic est souvent pris a tort pour une appendicite ou une cholecystite. Les auteurs rapportent le cas d’une jeune patiente ayant presente un syndrome appendiculaire avec la decouverte peroperatoire d’une diverticulite solitaire du caecum, en insistant sur les modalites diagnostiques et therapeutiques.

Introduction Le volvulus du sigmoide au cours de la grossesse est tres rare, environ 76 cas ont ete decrits dans la litterature mondiale.

North Africa is one of the most earthquake-prone areas of the Mediterranean. Many devastating earthquakes, some of them tsunami-triggering, inflicted heavy loss of life and considerable economic damage to the region. In order to mitigate the destructive impact of the earthquakes, the regional seismic hazard in North Africa is assessed using the neo-deterministic, multi-scenario methodology (NDSHA) based on the computation of synthetic seismograms, using the modal summation technique, at a regular grid of 0.2 × 0.2°. This is the first study aimed at producing NDSHA maps of North Africa including five countries: Morocco, Algeria, Tunisia, Libya, and Egypt. The key input data for the NDSHA algorithm are earthquake sources, seismotectonic zonation, and structural models. In the preparation of the input data, it has been really important to go beyond the national borders and to adopt a coherent strategy all over the area. Thanks to the collaborative efforts of the teams involved, it has been possible to properly merge the earthquake catalogues available for each country to define with homogeneous criteria the seismogenic zones, the characteristic focal mechanism associated with each of them, and the structural models used to model wave propagation from the sources to the sites. As a result, reliable seismic hazard maps are produced in terms of maximum displacement (D max), maximum velocity (V max), and design ground acceleration.

Based on passive seismic interferometry applied to ambient seismic noise recordings between station pairs belonging to a small-scale array, we have obtained shear wave velocity images of the uppermost materials that make up the Dead Sea Basin. We extracted empirical Green’s functions from cross-correlations of long-term recordings of continuous data, and measured inter-station Rayleigh wave group velocities from the daily correlation functions for positive and negative correlation time lags in the 0.1–0.5 Hz bandwidth. A tomographic inversion of the travel times estimated for each frequency is performed, allowing the laterally varying 3-D surface wave velocity structure below the array to be retrieved. Subsequently, the velocity-frequency curves are inverted to obtain S-wave velocity images of the study area as horizontal depth sections and longitude- and latitude-depth sections. The results, which are consistent with other previous ones, provide clear images of the local seismic velocity structure of the basin. Low shear velocities are dominant at shallow depths above 3.5 km, but even so a spit of land with a depth that does not exceed 4 km is identified as a salt diapir separating the low velocities associated with sedimentary infill on both sides of the Lisan Peninsula. The lack of low speeds at the sampling depth of 11.5 km implies that there are no sediments and therefore that the basement is near 10–11 km depth, but gradually decreasing from south to north. The results also highlight the bowl-shaped basin with poorly consolidated sedimentary materials accumulated in the central part of the basin. The structure of the western margin of the basin evidences a certain asymmetry both whether it is compared to the eastern margin and it is observed in north–south direction. Infill materials down to ∼8 km depth are observed in the hollow of the basin, unlike what happens in the north and south where they are spread beyond the western Dead Sea shore.

Colorectal carcinoma during pregnancy is very rare. Prognosis is severe because of the advanced stage due to delay in diagnosis and the aggressiveness of this widespread metastatic disease. We present two cases of colorectal cancers, discovered during pregnancy, as well as the results of a literature review to apprehend this clinical situation, and we describe recommended medical and surgical management.

Le syndrome de Bouveret est une obstruction pyloroduodenale par un calcul biliaire ayant migre a travers une fistule cholecystoduodenale. Nous rapportons le cas d’un patient de 59 ans presentant des epigastralgies et des vomissements. L’echographie abdominale et le transit œsogastroduodenal ont objective un enorme estomac de stase en amont d’une stenose tres serree postbulbaire. La laparotomie a retrouve un gros calcul dans le duodenum avec fistule cholecystoduodenale. Il a beneficie d’une chirurgie en un temps. Les suites postoperatoires etaient simples.

Up to now, dispersion analysis of surface waves at the short period across the southem region of the Iberian peninsula has never been investigated. In this study, group velocity dispersion was deterrnined for Rayleigh waves between of 1.5 and 6.0 s generated by local earthquakes in sourthem of Spain and Alboran sea (mediterranean sea). A total of 18 seismie events were studied occured between 1990 and 1995. The events were recorded at a single component station belonging to the Regional seismie Network of Andalucia. To remove higher-move interference efficiently and to impore isolation of the fundamentalmode Rayleigh wave from the seismograms, time-variable filtering is employed. Once the signal, multiple filtered is then used to compute group veloeities in each station. We carried out inversion of velocity dispersion data containing Rayleigh-wave group veloeities according to the generalized inversion theory by means of the stochastic inversion operator. We have obtained shear velocity value beteween 0 and 4 Km.The paths of these surface waves go throw various geologie structures, and different dispersion regions have been identified. The inversion results suggest the existence of some degree of lateral variation of shear wave velocity in the region and we observed a good correlation between those changes and the contrasting geology between adjacent geological forrnation.

The seismic velocity structure of the Granada Basin (southern Spain) at depths of 1-4 km is investigated by dispersion analysis of 0.5- to 5.9-sec Rayleigh waves. We have used records from 12 quarry blasts detonated between 1990 and 2000 and 16 local earthquakes with magnitudes between 2.6 and 3.8 that occurred between 1990 and 1997. All events were recorded on the Regional Seismic Network of Andalucia, Spain, and on the National Seismic Network. P -, S - and Rg -phases were recorded at 13 stations at distances between 10 and 72 km from the source. The analysis and inversion of Rg waveforms is performed using multiple filtering techniques and a generalized inversion approach. We measured ray-path group velocities from 0.83 to 2.15 km/sec in the 0.6- to 5.8-sec period interval, and obtained shear-wave velocity profiles for 29 source-station paths. The shear velocities lie between 0.8 and 3.34 km/sec within a standard deviation band of 0.05-0.14 km/sec. From these models, it is possible to infer the most conspicuous features in the upper 4 km of the region and the existence of some degree of lateral variation in velocity. After applying an imaging method aimed at volumetric modeling and data visualization, we present the first velocity images obtained for the Granada Basin. Our results characterize the basin and are correlated with the surface geology. Manuscript received 7 September 2001.