Articoli di riviste: "Discontinuité du Moho"

1

Khamrabaev, I. KH. "Nature of the Moho discontinuity in Central Asia". Global Tectonics and Metallogeny 6, n. 3-4 (1 gennaio 1998): 199–204. http://dx.doi.org/10.1127/gtm/6/1998/199.

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Hyndman, Roy D. "Tectonic Consequences of a Uniformly Hot Backarc and Why is the Cordillera Mountain Belt High?" Geoscience Canada 42, n. 4 (7 dicembre 2015): 383. http://dx.doi.org/10.12789/geocanj.2015.42.078.

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SUMMARYWhy is the North American Cordilleran mountain belt high? We expect a thick crust to support high elevations by isostasy but, remarkably, the Cordilleran crust is thin. There is no crustal root. An important recent recognition is that the high elevation is supported by thermal expansion rather than by thickened crust. The elevation of the Cordillera is only one consequence of the Cordillera being uniformly hot and having a thin lithosphere, in common with most current or recent backarcs. Some other consequences of the high temperatures compared to the adjacent cool craton include: (1) The Cordillera and other backarcs are hot, weak mobile belts that can be deformed by available plate-tectonic forces, in contrast to stable cratons that cannot; (2) Most continental seismicity is concentrated in backarcs; (3) In the Cordillera there is widespread sporadic ‘backarc’ volcanism; (4) The high temperatures result in very low strength in the lower crust that allows lower-crust detachment; (5) The lower crust weakness facilitates large-scale crustal oroclines that may be independent of the upper mantle; (6) The lower crust in the Cordillera and other backarcs is in amphibolite- to granulite-facies conditions, ~800–900°C at the Moho; (7) In ancient backarcs globally, regional Barrovian metamorphism is concluded to be the result of high temperatures that predate the orogenic collision and deformation. No "heat of orogeny" is required. Following the termination of subduction, backarcs cool with a time constant of 300–500 m.y.RÉSUMÉPourquoi la chaîne de montagnes de la Cordillère nord-américaine est-elle si haute? On comprend qu’une croûte sur-épaisse puisse expliquer une grande élévation, mais voilà, la croûte de la Cordillère est mince. Il n’existe pas de racine crustale. Or, récemment, une conclusion importante s’est imposée, soit que cette haute élévation s’explique par l’expansion thermique plutôt que par l’existence d’une croûte sur-épaisse. L’élévation de la Cordillère n’est qu’une des conséquences d’une Cordillère uniformément chaude flottant sur une lithosphère mince, caractéristiques communes aux zones d’arrière-arc actuelles ou récentes. Quelques unes des autres conséquences de cette haute température, par opposition aux froids cratons adjacents, comprennent: (1) La Cordillère et d’autres zones d’arrières-arcs sont des zones chaudes et facilement déformables par les forces tectoniques ambiantes, contrairement aux cratons stables; (2) La majorité de l’activité sismique continentale est concentrée dans le zones d’arrière-arc; (3) Dans la Cordillère l’activité volcanique sporadique est généralisé; (4) Ces températures élevées explique la très faible rigidité de la croûte inférieure et les décollements qu’elle subit; (5) La flaccidité de la croûte inférieure facilite la formation d’oroclinaux de grandes magnitudes qui peuvent être indépendants du manteau supérieur; (6) La croûte inférieure de la Cordillère et d’autres zones d’arrière-arc sont dans la zone de faciès amphibolite à granulite, soit 800 à 900oC à la discontinuité Moho; (7) Globalement dans les anciennes zones d’arrière-arc, le métamorphisme régional barrovien s’explique alors comme étant le résultat des hautes températures antérieures à la collision et à la déformation orogénique. Aucune « chaleur orogénique » n’est nécessaire. Après la période de subduction, les zones d’arrière-arc se refroidissent à l’intérieur d’un intervalle de temps de 300 à 500 millions d’années.

3

Kravchenko, S., L. I. Schachotko e I. T. Rass. "Moho discontinuity relief and the distribution of kimberlites and carbonatites in the northern Siberian Platform". Global Tectonics and Metallogeny 6, n. 2 (31 luglio 1996): 137–40. http://dx.doi.org/10.1127/gtm/6/1996/137.

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4

Agarwal, B. N. P., e R. K. Shaw. "Three dimensional configuration of Moho discontinuity over some parts of India from gravity field data". Global Tectonics and Metallogeny 7, n. 1 (1 gennaio 1999): 13. http://dx.doi.org/10.1127/gtm/7/1999/13.

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5

Riazkov, Hristo. "The Moho discontinuity on the Balkan Peninsula and some geodynamic problems". Geologica Balcanica 22, n. 2 (30 aprile 1992): 81–93. http://dx.doi.org/10.52321/geolbalc.22.2.81.

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The scheme of Moho's relief is built on 104 points based on seismologic and DSS data. The regional and residual trends are determined for this relief. On the basis of their analysis and of a priori geological and geophysical information three models (diapir, microplate and subduction) of the Balkan peninsula are briefly examined.

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Skoko, D., E. Prelogovič e B. Alinovič. "Geological structure of the Earth's crust above the Moho discontinuity in Yugoslavia". Geophysical Journal International 89, n. 1 (aprile 1987): 379–82. http://dx.doi.org/10.1111/j.1365-246x.1987.tb04434.x.

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7

Susena, P. K. O., P. Ariyanto, B. Pranata, Daryono e S. P. Adi. "Depth Estimation of Moho Discontinuity Layer at 5 BMKG Seismic Stations in East Java Using Receiver Function Method". IOP Conference Series: Earth and Environmental Science 1288, n. 1 (1 dicembre 2023): 012007. http://dx.doi.org/10.1088/1755-1315/1288/1/012007.

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Abstract East Java is one of the areas with a high level of seismicity due to the existence of a subduction zone in the south of Java Island. In addition, there are also active faults and active volcanos in East Java. This study aims to determine the depth of the Moho Discontinuity layer and subduction slab using receiver function method based on the iterative time domain deconvolution. This study was conducted using teleseismic earthquake data with an epicenter distance of 30°–90° from the receiver station and magnitude more than 6 (M≥6). 5 BMKG seismic stations that form a straight line are used, including those in the Bawean Arc (BWJI), Rembang Zone (BAJI), Kendeng Zone (SIJM), Modern Mountain Arc (PPJI), Southern Mountain Zone (GEJI). The depth of the Moho Discontinuity layer at BWJI Station was observed in ranges from 36–38 km, at BAJI Station it ranges from 39–40 km, at SIJM Station it ranges from 39–40 km, at PPJI Station it ranges from 46–48 km, and at GEJI Station it ranges from 33–36 km. In general, the Moho Discontinuity layer in the mountainous region is deeper due to the isostasy effect.

8

Michailos, Konstantinos, György Hetényi, Matteo Scarponi, Josip Stipčević, Irene Bianchi, Luciana Bonatto, Wojciech Czuba et al. "Moho depths beneath the European Alps: a homogeneously processed map and receiver functions database". Earth System Science Data 15, n. 5 (24 maggio 2023): 2117–38. http://dx.doi.org/10.5194/essd-15-2117-2023.

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Abstract. We use seismic waveform data from the AlpArray Seismic Network and three other temporary seismic networks, to perform receiver function (RF) calculations and time-to-depth migration to update the knowledge of the Moho discontinuity beneath the broader European Alps. In particular, we set up a homogeneous processing scheme to compute RFs using the time-domain iterative deconvolution method and apply consistent quality control to yield 112 205 high-quality RFs. We then perform time-to-depth migration in a newly implemented 3D spherical coordinate system using a European-scale reference P and S wave velocity model. This approach, together with the dense data coverage, provide us with a 3D migrated volume, from which we present migrated profiles that reflect the first-order crustal thickness structure. We create a detailed Moho map by manually picking the discontinuity in a set of orthogonal profiles covering the entire area. We make the RF dataset, the software for the entire processing workflow, as well as the Moho map, openly available; these open-access datasets and results will allow other researchers to build on the current study.

9

Wang, Hsiao-Lan, How-Wei Chen e Lupei Zhu. "Constraints on average Taiwan Reference Moho Discontinuity Model-receiver function analysis using BATS data". Geophysical Journal International 183, n. 1 (25 agosto 2010): 1–19. http://dx.doi.org/10.1111/j.1365-246x.2010.04692.x.

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Boykova, Antoaneta. "Moho discontinuity in central Balkan Peninsula in the light of the geostatistical structural analysis". Physics of the Earth and Planetary Interiors 114, n. 1-2 (luglio 1999): 49–58. http://dx.doi.org/10.1016/s0031-9201(99)00045-x.

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Aboud, Essam, Abdulrahman M. Alotaibi e Ramzi Saud. "Relationship between Curie isotherm surface and Moho discontinuity in the Arabian shield, Saudi Arabia". Journal of Asian Earth Sciences 128 (ottobre 2016): 42–53. http://dx.doi.org/10.1016/j.jseaes.2016.07.025.

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Teng, Jiwen, Zhongjie Zhang, Xiankang Zhang, Chunyong Wang, Rui Gao, Baojun Yang, Yonghu Qiao e Yangfan Deng. "Investigation of the Moho discontinuity beneath the Chinese mainland using deep seismic sounding profiles". Tectonophysics 609 (dicembre 2013): 202–16. http://dx.doi.org/10.1016/j.tecto.2012.11.024.

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13

Giese, P., E. Scheuber, F. Schilling, M. Schmitz e P. Wigger. "Crustal thickening processes in the Central Andes and the different natures of the Moho-discontinuity". Journal of South American Earth Sciences 12, n. 2 (marzo 1999): 201–20. http://dx.doi.org/10.1016/s0895-9811(99)00014-0.

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Matsubara, Makoto, Hiroshi Sato, Tatsuya Ishiyama e Anne Van Horne. "Configuration of the Moho discontinuity beneath the Japanese Islands derived from three-dimensional seismic tomography". Tectonophysics 710-711 (luglio 2017): 97–107. http://dx.doi.org/10.1016/j.tecto.2016.11.025.

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Katsumata, Akio, e Noriko Kamaya. "Low-frequency continuous tremor around the Moho discontinuity away from volcanoes in the southwest Japan". Geophysical Research Letters 30, n. 1 (gennaio 2003): 20–1. http://dx.doi.org/10.1029/2002gl015981.

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Kind, R., T. Eken, F. Tilmann, F. Sodoudi, T. Taymaz, F. Bulut, X. Yuan, B. Can e F. Schneider. "Thickness of the lithosphere beneath Turkey and surroundings from S-receiver functions". Solid Earth Discussions 7, n. 2 (10 aprile 2015): 1315–46. http://dx.doi.org/10.5194/sed-7-1315-2015.

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Abstract. We analyze S-receiver functions to investigate the variations of lithospheric thickness below the entire region of Turkey and surroundings. The teleseismic data used here have been compiled combining all permanent seismic stations which are open to public access. We obtained almost 12 000 S-receiver function traces characterizing the seismic discontinuities between the Moho and the discontinuity at 410 km depth. Common-conversion-points stacks yield well-constrained images of the Moho and of the lithosphere–asthenosphere boundary (LAB). Results from previous studies suggesting shallow LAB depths between 80 and 100 km are confirmed in the entire region outside the subduction zones. We did not observe changes of LAB depths across the North and East Anatolian Faults. To the east of Cyprus, we see indications of the Arabian LAB. The African plate is observed down to about 150 km depth subducting to the north and east between the Aegean and Cyprus with a tear at Cyprus. We also observed the discontinuity at 410 km depth and a negative discontinuity above the 410, which might indicate a zone of partial melt above this discontinuity.

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Kind, R., T. Eken, F. Tilmann, F. Sodoudi, T. Taymaz, F. Bulut, X. Yuan, B. Can e F. Schneider. "Thickness of the lithosphere beneath Turkey and surroundings from S-receiver functions". Solid Earth 6, n. 3 (31 luglio 2015): 971–84. http://dx.doi.org/10.5194/se-6-971-2015.

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Abstract. We analyze S-receiver functions to investigate variations of lithospheric thickness below the entire region of Turkey and surrounding areas. The teleseismic data used here have been compiled combining all permanent seismic stations which are open to public access. We obtained almost 12 000 S-receiver function traces characterizing the seismic discontinuities between the Moho and the discontinuity at 410 km depth. Common-conversion-point stacks yield well-constrained images of the Moho and of the lithosphere–asthenosphere boundary (LAB). Results from previous studies suggesting shallow LAB depths between 80 and 100 km are confirmed in the entire region outside the subduction zones. We did not observe changes in LAB depths across the North and East Anatolian faults. To the east of Cyprus, we see indications of the Arabian LAB. The African plate is observed down to about 150 km depth subducting to the north and east between the Aegean and Cyprus with a tear at Cyprus. We also observed the discontinuity at 410 km depth and a negative discontinuity above the 410, which might indicate a zone of partial melt above this discontinuity.

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Schlaphorst, David, Elena Melekhova, J.-Michael Kendall, Jon Blundy e Joan L. Latchman. "Probing layered arc crust in the Lesser Antilles using receiver functions". Royal Society Open Science 5, n. 11 (novembre 2018): 180764. http://dx.doi.org/10.1098/rsos.180764.

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Oceanic arcs can provide insight into the processes of crustal growth and crustal structure. In this work, changes in crustal thickness and composition along the Lesser Antilles Arc (LAA) are analysed at 10 islands using receiver function (RF) inversions that combine seismological data with v P /v S ratios estimated based on crustal lithology. We collected seismic data from various regional networks to ensure station coverage for every major island in the LAA from Saba in the north to Grenada in the south. RFs show the subsurface response of an incoming signal assuming horizontal layering, where phase conversions highlight discontinuities beneath a station. In most regions of the Earth, the Mohorovičić discontinuity (Moho) is seismically stronger than other crustal discontinuities. However, in the LAA we observe an unusually strong along-arc variation in depth of the strongest discontinuity, which is difficult to explain by variations in crustal thickness. Instead, these results suggest that in layered crust, especially where other discontinuities have a stronger seismic contrast than the Moho, H– k stacking results can be easily misinterpreted. To circumvent this problem, an inversion modelling approach is introduced to investigate the crustal structure in more detail by building a one-dimensional velocity–depth profile for each island. Using this method, it is possible to identify any mid-crustal discontinuity in addition to the Moho. Our results show a mid-crustal discontinuity at about 10–25 km depth along the arc, with slightly deeper values in the north (Montserrat to Saba). In general, the depth of the Moho shows the same pattern with values of around 25 km (Grenada) to 35 km in the north. The results suggest differences in magmatic H 2 O content and differentiation history of each island.

19

Zarkasi, M. H., P. Ariyanto, A. Marsono, B. Pranata, Daryono e S. P. Adi. "Moho Depth Estimation and The Presence of Subducting Slab in West Sumatra, Jambi, and Riau Islands Regions Using Teleseismic Receiver Function Method: A Preliminary Result". IOP Conference Series: Earth and Environmental Science 1288, n. 1 (1 dicembre 2023): 012011. http://dx.doi.org/10.1088/1755-1315/1288/1/012011.

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Abstract The teleseismic receiver function method was used to investigate the crustal structure in West Sumatra, Jambi, and Riau Islands regions. These regions have a high level of seismicity because it is in an active tectonic zone where the oblique subduction between the Indo-Australian and Eurasian plates occurs. This study aims to determine the depth of Moho discontinuity and the presence of subducting slab beneath 6 BMKG seismic stations that form a line perpendicular to the trench and cover 3 different geological zones. PPSI and RASM are in the forearc zone, SKSM is in the volcanic arc zone, and MBBI, JMBI, and DSRI are in the back-arc zone. This study used teleseismic earthquake record data with epicentral distance between 30°-90° from the receiver and magnitude 6 or more. The iterative time-domain deconvolution and receiver function migration techniques were applied to estimate the depth of Moho discontinuity and the presence of subducting slab. The depth of Moho discontinuity in West Sumatra, Jambi, and Riau Islands regions ranges from 21-39 km and generally deeper in the volcanic arc zone possibly due to the isostatic effect. Moho is at a depth of 21-29 km in the forearc zone, 36-39 km in the volcanic arc zone, and 30-36 km in the back-arc zone. Then the subducting slab was observed at a depth of 20 km under PPSI station to 200 km under MBBI station.

20

Peng, Xiaohua, e Eugene D. Humphreys. "Moho dip and crustal anisotropy in northwestern Nevada from teleseismic receiver functions". Bulletin of the Seismological Society of America 87, n. 3 (1 giugno 1997): 745–54. http://dx.doi.org/10.1785/bssa0870030745.

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Abstract Receiver functions are derived from teleseismic waves recorded during the 1988 to 1989 PASSCAL Basin and Range passive-source seismic experiment in northwestern Nevada. A velocity model involving both a planar dipping Moho and crustal anisotropy is needed to explain the radial and tangential motions of the observed PS conversions. An arrival-time difference often observed between radial and tangential Moho PS conversions suggests an anisotropic crust. The PS conversions are large and indicate a major discontinuity under the area. The particle motion directions for most of the tangential components change sign between South American events and events from the other two source areas (Japan and Tonga regions), providing good evidence for a Moho dipping approximately to the north. Also, the PS conversions from the Moho follow direct P arrivals by about 3.2 sec under the southern part of the array, 3.4 sec under the southern central part of the array, and 3.7 sec under the northern part of the array, indicating a Moho that varies in depth from about 26 to 31 km. A velocity model with the Moho dipping ∼9° in a nearly northerly direction and an anisotropic crust with a split time of ∼0.25 sec and a fast axis of ∼130° best explain these observations.

21

Pratama, R., P. Ariyanto, A. Wijaya e S. Ariwibowo. "Identification of Moho Discontinuity Depth Variations and Subduction Slab in North Sumatra Region Using Receiver Function Method". Journal of Physics: Conference Series 1491 (marzo 2020): 012052. http://dx.doi.org/10.1088/1742-6596/1491/1/012052.

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Eshagh, Mehdi, e Matloob Hussain. "An approach to Moho discontinuity recovery from on-orbit GOCE data with application over Indo-Pak region". Tectonophysics 690 (ottobre 2016): 253–62. http://dx.doi.org/10.1016/j.tecto.2016.07.003.

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23

Huang, Jin-li, e Da-peng Zhao. "P-wave tomography of crust and upper mantle under Southern California: Influence of topography of Moho discontinuity". Acta Seismologica Sinica 16, n. 6 (novembre 2003): 577–87. http://dx.doi.org/10.1007/s11589-003-0041-6.

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Eli Baker, G., J. Bernard Minster, George Zandt e H. Gurrola. "Constraints on crustal structure and complex Moho topography beneath Piñon Flat, California, from teleseismic receiver functions". Bulletin of the Seismological Society of America 86, n. 6 (1 dicembre 1996): 1830–44. http://dx.doi.org/10.1785/bssa0860061830.

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Abstract We use teleseismic P waves recorded at Piñon Flat Observatory (PFO) to constrain the three-dimensional crustal and upper-mantle velocity structure beneath the station. By forward modeling radial receiver function waveforms, we construct a one-dimensional crustal model that includes a significant shear-velocity inversion at 9 km in depth. Arrivals on the tangential components indicate dip of at least the uppermost discontinuity. Complicated Moho topography, deepening to the northwest of PFO, is suggested by azimuthal dependence of travel times and amplitudes of the receiver functions and travel times of crustal P-wave reverberations. Although fine details cannot be resolved, each of those sets of observations plus mislocation vectors provide strong indications of abrupt Moho topography, possibly including step offsets of several kilometers. This is not only consistent with gravity data in implying Airy isostasy with compensation at Moho depth but extends that model to a much finer length scale than had been resolved.

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Shanov, Stefan, e Iavor Kostadinov. "Configuration of the deep geophysical discontinuities beneath the territory of Bulgaria". Geologica Balcanica 22, n. 2 (30 aprile 1992): 71–79. http://dx.doi.org/10.52321/geolbalc.22.2.71.

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All known data about the depth of the Mohorovičić and Conrad discontinuities and for the base of the lithosphere have been analysed for Bulgaria and the adjacent territories. Maps for these surfaces, as well as for the thicknesses of the layers between them have been constructed with the aid of professional and precisely tested mathematic algorithms. The physical nature of each geophysical surface is commented. The Moho discontinuity represents the lower boundary of the Earth's crust, and in our interpretation differs considerably from the maps published up to now. The Conrad discontinuity is considered as a physical boundary which is bounding rock volumes with different physico-mechanical properties due to change in the stress field in the rocks. This surface is not conformable to Moho. The lower boundary of the lithosphere determines the level of elevation of the asthenosphere into the upper mantle. The maps may be used for interpretation of the geological and geophysical information relative to the geodynamics, structure, magmatism and metamorphism of the lithosphere in this part of the Balkan Peninsula.

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Kind, R., X. Yuan, J. Mechie e F. Sodoudi. "Structure of the upper mantle in the north-western and central United States from USArray S-receiver functions". Solid Earth 6, n. 3 (31 luglio 2015): 957–70. http://dx.doi.org/10.5194/se-6-957-2015.

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Abstract. We used more than 40 000 S-receiver functions recorded by the USArray project to study the structure of the upper mantle between the Moho and the 410 km discontinuity from the Phanerozoic western United States to the cratonic central US. In the western United States we observed the lithosphere–asthenosphere boundary (LAB), and in the cratonic United States we observed both the mid-lithospheric discontinuity (MLD) and the LAB of the craton. In the northern and southern United States the western LAB almost reaches the mid-continental rift system. In between these two regions the cratonic MLD is surprisingly plunging towards the west from the Rocky Mountain Front to about 200 km depth near the Sevier thrust belt. We interpret these complex structures of the seismic discontinuities in the mantle lithosphere as an indication of interfingering of the colliding Farallon and Laurentia plates. Unfiltered S-receiver function data reveal that the LAB and MLD are not single discontinuities but consist of many small-scale laminated discontinuities, which only appear as single discontinuities after longer period filtering. We also observe the Lehmann discontinuity below the LAB and a velocity reduction about 30 km above the 410 km discontinuity.

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Kind, R., X. Yuan, J. Mechie e F. Sodoudi. "Structure of the upper mantle in the north-western and central United States from USArray S-receiver functions". Solid Earth Discussions 7, n. 1 (6 marzo 2015): 1025–57. http://dx.doi.org/10.5194/sed-7-1025-2015.

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Abstract. We used more than 40 000 S-receiver functions recorded by the USArray project to study the structure of the upper mantle between the Moho and the 410 km discontinuity from the Phanerozoic western United States to the cratonic central US. We obtained clear observations of downward velocity reductions in the uppermost mantle which are commonly interpreted as the lithosphere-asthenosphere boundary (LAB) in the western US and as the mid-lithospheric discontinuity (MLD) in the cratonic US. We observe the western LAB reaching partly to the mid-continental rift system underneath the cratonic crust. The MLD is surprisingly plunging steeply towards the west from the Rocky Mountains Front to about 200 km depth near the Sevier Thrust Belt. There is a significant break in the lithosphere at the Sevier Thrust Belt. We also observe a velocity reduction about 30 km above the 410 km discontinuity in the same region where in the western US the LAB is observed, but not in the cratonic US.

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Prutkin, Ilya, e Ahmed Saleh. "Gravity and magnetic data inversion for 3D topography of the Moho discontinuity in the northern Red Sea area, Egypt". Journal of Geodynamics 47, n. 5 (maggio 2009): 237–45. http://dx.doi.org/10.1016/j.jog.2008.12.001.

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Hsu, Hsuan-Ju, Strong Wen e Chau-Huei Chen. "3D topography of the Moho discontinuity in the Taiwan area as extracted from travel time inversion of PmP phases". Journal of Asian Earth Sciences 41, n. 3 (maggio 2011): 335–43. http://dx.doi.org/10.1016/j.jseaes.2011.02.003.

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Ariyanto, P., A. A. B. Al-Hakim, B. Pranata, Daryono e S. P. Adi. "Identification of Moho Discontinuity Depth and Subduction Slab in Bengkulu and South Sumatra Region using Receiver Function Method: A Preliminary Result". IOP Conference Series: Earth and Environmental Science 1288, n. 1 (1 dicembre 2023): 012012. http://dx.doi.org/10.1088/1755-1315/1288/1/012012.

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Abstract Bengkulu and South Sumatra regions are areas with high seismic activity due to faults and subduction zones. This study aims to analyze the depth of the Moho discontinuity layer and subduction slab under 4 BMKG seismic stations that form a perpendicular line of trench in the Bengkulu and South Sumatra areas. The distribution of stations used are Enggano Station (EGSI) in the front arc islands, Manna Station (MNAI) in the front arc basin, Pagar Alam Station (PKSI) in the volcanic-arc zone, and Lahat Station (LHSI) in the proto-volcanic zone. We selected teleseismic earthquake data with a distance of 30°-90° from the stations and magnitudes above 6 (M>6). For the identification of Moho and slab depths, we used analysis of receiver functions with iterative time domain deconvolution and migration of receiver functions with the AK-135 velocity model. The Oceanic Moho layer and the subduction slab under the EGSI Station were identified at depths of 34 km and 23 km respectively, under the MNAI Station the Moho layer and the subduction slab were identified at a depth of 18 km and 87 km respectively, under the PKSI Station the Moho layer and the subduction slab were identified at a depth of 34 km and 129 km respectively, and under the LHSI Station the Moho layer and subduction slab were identified at depths of 35 km and 175 km respectively.

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Fasiku, O. B., A. Mallam e A. U. Osagie. "CRUSTAL THICKNESS BENEATH UTAKO ABUJA USING RECEIVER FUNCTION ANALYSIS". Open Journal of Physical Science (ISSN: 2734-2123) 4, n. 2 (12 novembre 2023): 1–12. http://dx.doi.org/10.52417/ojps.v4i2.516.

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Understanding the Mohorovicc discontinuity (Moho depth) is crucial in unraveling the Earth’s subsurface structure. In this research, we present the report of the crustal thickness and the ratio of the primary wave to the shear wave velocities (p-to-s) beneath the seismic station located at the Nigerian Geological Survey Agency (NGSA) Abuja using Receiver Function Analysis (RFA). The primary objective of this study is to determine the depth of the Moho boundary and gain insights into the geological properties of the Earth’s crust and upper mantle beneath the receiver station. This analysis focused on teleseismic earthquakes that were recorded at the station between 2020 and 2021, with epicentere distances between 30o and 90o and magnitudes 5.5 or greater. The P wave Receiver Function (PRF) was modeled from iterative time domain deconvolution using the converted phases (Ps) at the Moho interface.

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Heydarizadeh Shali, H., D. Sampietro, A. Safari, M. Capponi e A. Bahroudi. "Fast collocation for Moho estimation from GOCE gravity data: the Iran case study". Geophysical Journal International 221, n. 1 (14 gennaio 2020): 651–64. http://dx.doi.org/10.1093/gji/ggaa026.

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SUMMARY The study of the discontinuity between crust and mantle beneath Iran is still an open issue in the geophysical community due to its various tectonic features created by the collision between the Iranian and Arabian Plate. For instance in regions such as Zagros, Alborz or Makran, despite the number of studies performed, both by exploiting gravity or seismic data, the depth of the Moho and also interior structure is still highly uncertain. This is due to the complexity of the crust and to the presence of large short wavelength signals in the Moho depth. GOCE observations are capable and useful products to describe the Earth’s crust structure either at the regional or global scale. Furthermore, it is plausible to retrieve important information regarding the structure of the Earth’s crust by combining the GOCE observations with seismic data and considering additional information. In the current study, we used as observation a grid of second radial derivative of the anomalous gravitational potential computed at an altitude of 221 km by means of the space-wise approach, to study the depth of the Moho. The observations have been reduced for the gravitational effects of topography, bathymetry and sediments. The residual gravity has been inverted accordingly to a simple two-layer model. In particular, this guarantees the uniqueness of the solution of the inverse problem which has been regularized by means of a collocation approach in the frequency domain. Although results of this study show a general good agreement with seismically derived depths with a root mean square deviation of 6 km, there are some discrepancies under the Alborz zone and also Oman sea with a root mean square deviation up 10 km for the former and an average difference of 3 km for the latter. Further comparisons with the natural feature of the study area, for instance, active faults, show that the resulting Moho features can be directly associated with geophysical and tectonic blocks.

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He, Kai, Rong Huang, Yixian Xu, Shaoqian Hu e Penglong Wei. "Crustal structures beneath the Northern Jiangsu Basin and its surrounding areas: implications for geothermal prospecting". Journal of Geophysics and Engineering 19, n. 3 (24 maggio 2022): 316–25. http://dx.doi.org/10.1093/jge/gxac018.

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Abstract Based on the recordings of 42 permanent seismic stations in Northern Jiangsu Basin (NJB) and its surrounding areas, we obtained both the sediment and crustal thickness in the region, using the nearest-neighbor algorithm and H–κ stacking method of receiver functions. We proposed a solution to use the sediment thickness to correct the depth of actual Moho discontinuity beneath the basin areas. Our results indicate that the sediment thickness in the northwest of the NJB is <1 km. We suggest that the southeastern border of the NJB should extend to the Yangzhou-Rudong area. The results of Moho variations show that the undulations of the Moho beneath the western NJB retains the traces of the sinistral shearing movement of the Tan-Lu Fault since the Miocene. Finally, we suggest the area around the Gaoyou city to be a prospective area for geothermal exploration.

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Mahardiana, R. I., P. Ariyanto, B. Pranata e B. S. Prayitno. "Comparison Study of Crustal Structure in Aceh Region based on Volcanic Arc System using Receiver Function Method". Journal of Physics: Conference Series 2110, n. 1 (1 novembre 2021): 012003. http://dx.doi.org/10.1088/1742-6596/2110/1/012003.

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Abstract Aceh region has a very complex crustal structure from the forearc ridge to the backarc basin. This study aims to determine the velocity model of P and S waves and the depth of Moho discontinuity. This research was conducted using teleseismic earthquake data (30°-90° from the station) with M>6 from four seismic stations belonging to the BMKG in Aceh region. The stations are qualified based on the volcanic arc system zone. Furthermore, the velocity model determined by result of forward modelling, while the depth of the Moho layer estimated by migrated receiver function from time domain to the depth domain. At station SNSI that represented the forearc ridge zone, the depth of Moho is ±28 km, at station TPTI represent the forearc basin is ±16 km, while at zone with higher topography, namely volcanic arc zone represented by station KCSI, the Moho depth was identified at ±38 km, and the backarc basin represented by station LASI with ±40 km depth of Moho. This variation occurs because the composition of the earth’s layers below the station is diverse also different topography for each station.

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Reguzzoni, Mirko, Daniele Sampietro e Lorenzo Rossi. "The gravimetric contribution to the Moho estimation in the presence of vertical density variations". Rendiconti Lincei. Scienze Fisiche e Naturali 31, S1 (11 agosto 2020): 69–81. http://dx.doi.org/10.1007/s12210-020-00940-8.

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Abstract The Moho surface, namely the density discontinuity between crust and mantle, is traditionally studied by seismic methods. However, gravity information can contribute to the Moho estimation and, more generally, to the crustal modeling. The contribution is twofold. First, gravimetry generally provides observations with much lower errors than those implied by the mass density uncertainty and other geophysical assumptions. This means that it can be used to validate existing Moho and/or crustal models by forward modeling. Second, gravity inversion is able to provide diffused (not localized) information on the mass distribution, both regionally and globally (thanks to dedicated satellite gravity missions). However, this information is weak due to its intrinsic ill-posedness. This means that it can be used to correct and spatially interpolate existing models, and to complement seismic, magnetic and geological information to create new models. In this work, the problem of estimating the Moho surface by gravity inversion assuming a two-layer model with lateral and vertical density variations is treated at a regional level. The approach consists in linearizing the forward modeling around a reference Moho at a constant depth and then inverting it through a Wiener filter. This is standard in case of two layers with homogeneous density distributions (or with lateral density variations), while it requires some additional considerations and algorithm modifications in case of vertical density variations. The basic idea is to “condensate” the masses inside the Moho undulation on the reference surface used for the linearization, thus requiring the setup of an iterative procedure. A strategy to introduce seismic information into this inversion procedure is proposed too, with the aim of improving the a priori density modeling. A closed loop test is presented for the algorithm assessment, showing the improvement with respect to a standard approach and the capability of the proposed algorithm to reconstruct the originally simulated Moho undulation by also fitting the gravity and seismic data at a level that is consistent with their observation noise.

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Liu, Lin, Simon L. Klemperer e Alexander R. Blanchette. "Western Gondwana imaged by S receiver-functions (SRF): New results on Moho, MLD (mid-lithospheric discontinuity) and LAB (lithosphere-asthenosphere boundary)". Gondwana Research 96 (agosto 2021): 206–18. http://dx.doi.org/10.1016/j.gr.2021.04.009.

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Bagherbandi, Mohammad, e Lars E. Sjöberg. "Modelling the density contrast and depth of the Moho discontinuity by seismic and gravimetric–isostatic methods with an application to Africa". Journal of African Earth Sciences 68 (giugno 2012): 111–20. http://dx.doi.org/10.1016/j.jafrearsci.2012.04.003.

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Kang, Hyunsun, YoungHee Kim, Junkee Rhie, Tae-Seob Kang e Marco Brenna. "Seismic crustal structure beneath Jeju Volcanic Island, South Korea from teleseismic P-receiver functions". Geophysical Journal International 227, n. 1 (29 maggio 2021): 58–75. http://dx.doi.org/10.1093/gji/ggab211.

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SUMMARY Jeju Island is an intraplate volcanic island with enigmatic origins, located on the continental shelf south of the Korean Peninsula. A dense temporary seismic array, operated on Jeju Island from 2013 to 2015, revealed several important constraints on the magma plumbing system of Jeju Island. In this study, we determined the deep crustal seismic structure beneath Jeju Island from the teleseismic P-to-S converted phases (receiver functions) recorded from 20 temporary and three permanent stations. We removed the contribution of near-surface reverberations in the resulting receiver functions by applying a resonance removal filter. We estimated crustal P-to-S velocity ratio (VP/VS) and discontinuity depth to provide teleseismic constraints on the composition and structure. We observed two major seismic discontinuities, which are the upper boundaries of a mid-to-lower crustal low-velocity zone (LVZ) and the Moho transition zone. The depth to the upper boundary of the LVZ is deep in the west and southeast (24–30 km) and shallow in the northeast (8–11 km). The LVZ can be interpreted as an extensively distributed residual magma plumbing system, with magma batches stalled at various levels and at various degrees of crystallization, consistent with the chemical diversity of Jeju magmas. The seismic characteristics of the Moho transition zone vary greatly among regions. The top interface of the Moho transition zone is at a wide range of depth (26–40 km), and is shallow at 26–29 km depths beneath central Jeju, suggesting a complex Moho topography. The presence of mafic cumulates and partially molten mushes may contribute to the observed shallow seismic discontinuity at a depth of 26–29 km. The lack of obvious crustal thickening below the shield volcano, Mt Halla, may be associated with mantle upwelling or presence of mafic underplating and cumulates below Jeju. Spatial variations of crustal VP/VS represent highly heterogeneous crustal composition, resulting from magma differentiation during the evolution of the island.

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Yang, Yang, Huanhuan Li, Zhigang Meng e Hengyu Wang. "A Method for Computing Slip-Line Fields with Stress Discontinuity in Cohesionless Backfills". Buildings 13, n. 3 (25 febbraio 2023): 610. http://dx.doi.org/10.3390/buildings13030610.

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A method for computing slip-line fields in the case of cohesionless backfills with stress discontinuity was proposed. The potential failure zone is divided into the Rankine zone and the transition zone, and the Rankine zone is rigorously determined using the theory of plastic mechanics. The potential failure zone and the Rankine zone are then further divided into a series of triangular slices. On the basis of the force and moment equilibrium conditions of a typical triangular slice, the recurrence equation of the lateral force is established. Furthermore, the relationship between the failure surface inclination angle and the interslice force inclination angle is established by satisfying the Mohr–Coulomb criterion. An iterative procedure for calculating the lateral force of the triangular slices by changing the failure surface inclination in the transition zone is performed until the interslice force satisfies the stress condition of the transition zone boundary, resulting in a stress discontinuity line if the Rankine zone and the transition zone intersect and the intersection line satisfies the stress characteristics of stress discontinuity. Example studies are performed to verify the present method, which shows that the soil–wall interface friction has the most significant effect on stress discontinuity, and the location of the stress discontinuity line gradually approaches the backfill surface with an increase in retaining wall inclination.

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Cook, Frederick A., Donald J. White, Alan G. Jones, David W. S. Eaton, Jeremy Hall e Ronald M. Clowes. "How the crust meets the mantle: Lithoprobe perspectives on the Mohorovičić discontinuity and crust–mantle transitionThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, n. 4 (aprile 2010): 315–51. http://dx.doi.org/10.1139/e09-076.

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Application of regional geophysical and geological methods throughout two decades of Canada’s Lithoprobe project provides new opportunities to analyze the Mohorovičić discontinuity (Moho) and crust–mantle transition. The transect format employed during Lithoprobe, in which 10 specified regions of Canada were targeted for approximately a decade each, between 1984 and 2003, permitted teams of scientists to focus on geological, geophysical, and tectonic issues for each transect. As a primary objective was to enhance knowledge of the structure of the crust and lithosphere, an obvious target in each transect was the nature and origin of the Moho and crust–mantle transition. Accordingly, the combined results provide new perspectives on the Moho and the relationship of the Moho to the crust–mantle transition. Perhaps the most important result is that the continental geophysical Moho is a deceptively simple feature; it has a variety of signatures at different scales that preclude a single, universally applicable interpretation. In methods that provide large-scale information, such as regional seismic studies, it is a relatively abrupt refraction velocity contrast that often displays a dramatic downward decrease in seismic reflectivity. However, its origin in a geological or tectonic sense is perhaps best determined by careful analyses of structural details near the geophysical Moho, which are complex and varied. In some areas within Canada, it appears that the geophysical Moho may be old and perhaps remains from the time the crust formed; in other areas, it appears to be a relatively young feature that was superimposed onto older crustal fabrics.

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Salem, Ahmed, Chris Green, Simon Campbell, J. Derek Fairhead, Lorenzo Cascone e Lee Moorhead. "Moho depth and sediment thickness estimation beneath the Red Sea derived from satellite and terrestrial gravity data". GEOPHYSICS 78, n. 5 (1 settembre 2013): G89—G101. http://dx.doi.org/10.1190/geo2012-0150.1.

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We sought to map the depth and density contrast of the Mohorovičić discontinuity (Moho) across the Red Sea area and to model sedimentary thickness from gravity data. The gravity data that are used are a combination of satellite and terrestrial gravity data processed into a Bouguer anomaly grid. A 200-km low-pass filter was used to separate this grid into regional and residual gravity grids. We inverted the regional gravity grid to a Moho depth map based on a density contrast map that is constrained by published seismic results. The interpreted Moho is shallowest ([Formula: see text]) along the axis of the central Red Sea, [Formula: see text] along the axis to the south, and [Formula: see text] in the northern Red Sea. The depth increased to [Formula: see text] at the coast and 35–40 km in the adjacent continents. The residual gravity data provided insights into the tectonic fabric along the whole rift and provided a good correlation with magnetic lineaments where these are available. We used the complete Bouguer anomaly to model sedimentary thicknesses constrained by wells and the interpreted Moho. The modeling results are consistent with the presence of large-scale, ridge parallel tilted fault blocks forming subbasins with a maximum depth of about 6–7 km. Our models suggest that the northern Red Sea has an asymmetric basement surface with the western side deeper than the eastern side. The results indicate the presence of oceanic crust in the central and southern parts of the Red Sea, but not in the north. The very thin crust and interpreted oceanic crustal density in the central Red Sea suggest that this area is fully oceanic—although possibly quite young.

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Di Salvo, Margherita. "PARALLELISMI E DISCONTINUITÀ IN DUE CONTESTI ANGLOFONI". Italiano LinguaDue 15, n. 1 (26 giugno 2023): 82–99. http://dx.doi.org/10.54103/2037-3597/20377.

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Questo contributo descrive i repertori linguistici degli italiani migrati stanziati a Toronto (Canada) e a Londra (Regno Unito); propone di mostrare la loro evoluzione nel corso delle diverse ondate migratorie, in modo da individuare somiglianze e divergenze tra i flussi degli anni Cinquanta e Sessanta e le migrazioni contemporanee. In tale prospettiva, obiettivo ultimo del contributo è evidenziare la criticità della nozione di heritage langauge così come applicata allo studio delle comunità italiane nel mondo e di suggerire modelli di lettura alternativi basati al concetto di repertorio linguistico. Parallelisms and discontinuities in two anglophone contexts This paper focuses on the linguistic repertoires of Italian migrants settled in two different cities, that are Toronto (in Canada) and London (in the UK). It aims to show their evolution during the various migratory waves and to identify similarities and differences between the flows that took place in the Fifties and in the Sixties and those that started after the recent crisis. The ultimate goal of the paper is to highlight the critical points of the heritage language approach as applied to the study of Italian communities worldwide: the paper aims of discuss alternative approaches based on the notion of linguistic multiple repertoire that has been recently proposed by several authors.

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Rahman, Nur Alam Syah, Ganda Marihot Simangunsong e Irwandi Arif. "Rock strength analysis due to discontinuity and grouting". Indonesian Mining Professionals Journal 2, n. 1 (28 novembre 2020): 29–36. http://dx.doi.org/10.36986/impj.v2i1.20.

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Instability on rock, one of many factors caused by joint. Decreased of rock strength occurred inline with existence a number of joints. Poor rock have a large number of joints. Therefore rock reinforcement such as grouting can be one of the solution. This research conducted on artificial sample Moldano Tara (dental stone type III). It had been given artificial joints with orientation 60o from axial and frequency 1 till 2. Furthermore, grout material with composition 4C;5W had been injected on joint and cured in 28 days. Triaxial test are done in all samples intact, jointed and grouted and its been analyzed with Mohr-Coulomb and Hoek Brown failure criteria. It is found, joint given negative contribution on shear strength, declining 65,75% and 73,48%, whereas on UCS declined 46,85% dan 56,19%. On the other hand, grouting had been given positive contribution on shear strength, increasing 166,15% and 188,07%, while UCS increased 46,60% and 60,92%

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Liu, Xin, e Dapeng Zhao. "Seismic evidence for a plume-modified oceanic lithosphere–asthenosphere system beneath Cape Verde". Geophysical Journal International 225, n. 2 (11 gennaio 2021): 872–86. http://dx.doi.org/10.1093/gji/ggab012.

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SUMMARY We determine a new 3-D shear wave velocity (Vs) model down to 400 km depth beneath the Cape Verde hotspot that is far from plate boundaries. This Vs model is obtained by using a new method of jointly inverting P- and S-wave receiver functions, Rayleigh-wave phase-velocity data and S-wave arrival times of teleseismic events. Two Vs discontinuities at ∼15 and ∼60 km depths are revealed beneath volcanic islands, which are interpreted as the Moho discontinuity and the Gutenberg (G) discontinuity. Between the north and south islands, obvious high-Vs anomalies exist in the uppermost mantle down to a depth of ∼100–150 km beneath the Atlantic Ocean, whereas obvious low-Vs anomalies exist in the uppermost mantle beneath the volcanic islands including the active Fogo volcano. These low-Vs anomalies merge into a significant column-like low-Vs zone at depths of ∼150–400 km beneath the Cape Verde swell. We propose that these features in the upper mantle reflect a plume-modified oceanic lithosphere–asthenosphere system beneath the Cape Verde hotspot.

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Hawksbee, Samuel, Colin Smith e Matthew Gilbert. "Application of discontinuity layout optimization to three-dimensional plasticity problems". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, n. 2155 (8 luglio 2013): 20130009. http://dx.doi.org/10.1098/rspa.2013.0009.

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A new three-dimensional limit analysis formulation that uses the recently developed discontinuity layout optimization (DLO) procedure is described. With DLO, limit analysis problems are formulated purely in terms of discontinuities, which take the form of polygons when three-dimensional problems are involved. Efficient second-order cone programming techniques can be used to obtain solutions for problems involving Tresca and Mohr–Coulomb yield criteria. This allows traditional ‘upper bound’ translational collapse mechanisms to be identified automatically. A number of simple benchmark problems are considered, demonstrating that good results can be obtained even when coarse numerical discretizations are employed.

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Kumar, Naresh, A. Aoudia, M. Guidarelli, Vivek G. Babu, Devajit Hazarika e D. K. Yadav. "Delineation of lithosphere structure and characterization of the Moho geometry under the Himalaya–Karakoram–Tibet collision zone using surface-wave tomography". Geological Society, London, Special Publications 481, n. 1 (2019): 19–40. http://dx.doi.org/10.1144/sp481-2017-172.

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AbstractGroup velocities for a period range of 6–60 s for the fundamental mode of the Rayleigh wave passing across the Himalaya–Karakoram–Tibet orogen are used to delineate the structure of the upper lithosphere using the data from 35 broadband seismic stations. 2D tomography velocity maps of group velocities were obtained at grids of 1° separation. Redefined local dispersion curves are inverted non-linearly to obtain 1D velocity models and to construct a 3D image of the S-wave structure down to a depth of 90 km.The Moho discontinuity is correlated with c. 4.0 km s−1 S-wave velocity. The results depict a NE-dipping trend of the Moho depth from c. 40 km beneath the frontal part of the Himalaya to up to c. 70–80 km beneath the collision zone before shallowing substantially to c. 40 km beneath the Tarim Basin. The study also reveals thick deposits of sediments in the Indo-Gangetic plains and the Tarim Basin. A broad low-velocity zone at mid-crustal depth in the western Tibetan Plateau, the Karakoram region and the surface-collision part of the India–Eurasia tectonic plates is interpreted as the effect of partial melting and/or the presence of aqueous fluid. The high velocities in the southern deeper part indicate that the lower crust and uppermost mantle of the Indian Plate are dense and cold.

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Kono, Yoshio, Masahiro Ishikawa, Yumiko Harigane, Katsuyoshi Michibayashi e Makoto Arima. "P- and S-wave velocities of the lowermost crustal rocks from the Kohistan arc: Implications for seismic Moho discontinuity attributed to abundant garnet". Tectonophysics 467, n. 1-4 (marzo 2009): 44–54. http://dx.doi.org/10.1016/j.tecto.2008.12.010.

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Abrehdary, Majid, e Lars E. Sjöberg. "Estimating a combined Moho model for marine areas via satellite altimetric - gravity and seismic crustal models". Studia Geophysica et Geodaetica 64, n. 1 (5 dicembre 2019): 1–25. http://dx.doi.org/10.1007/s11200-019-1067-0.

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AbstractIsostasy is a key concept in geoscience in interpreting the state of mass balance between the Earth’s lithosphere and viscous asthenosphere. A more satisfactory test of isostasy is to determine the depth to and density contrast between crust and mantle at the Moho discontinuity (Moho). Generally, the Moho can be mapped by seismic information, but the limited coverage of such data over large portions of the world (in particular at seas) and economic considerations make a combined gravimetric-seismic method a more realistic approach. The determination of a high-resolution of the Moho constituents for marine areas requires the combination of gravimetric and seismic data to diminish substantially the seismic data gaps. In this study, we estimate the Moho constituents globally for ocean regions to a resolution of 1° × 1° by applying the Vening Meinesz-Moritz method from gravimetric data and combine it with estimates derived from seismic data in a new model named COMHV19. The data files of GMG14 satellite altimetry-derived marine gravity field, the Earth2014 Earth topographic/bathymetric model, CRUST1.0 and CRUST19 crustal seismic models are used in a least-squares procedure. The numerical computations show that the Moho depths range from 7.3 km (in Kolbeinsey Ridge) to 52.6 km (in the Gulf of Bothnia) with a global average of 16.4 km and standard deviation of the order of 7.5 km. Estimated Moho density contrasts vary between 20 kg m-3 (north of Iceland) to 570 kg m-3 (in Baltic Sea), with a global average of 313.7 kg m-3 and standard deviation of the order of 77.4 kg m-3. When comparing the computed Moho depths with current knowledge of crustal structure, they are generally found to be in good agreement with other crustal models. However, in certain regions, such as oceanic spreading ridges and hot spots, we generally obtain thinner crust than proposed by other models, which is likely the result of improvements in the new model. We also see evidence for thickening of oceanic crust with increasing age. Hence, the new combined Moho model is able to image rather reliable information in most of the oceanic areas, in particular in ocean ridges, which are important features in ocean basins.

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Belashev, Boris, Lyubov Bakunovich, Nikolai Sharov e Michail Nilov. "Seismic Density Model of the White Sea’s Crust". Geosciences 10, n. 12 (7 dicembre 2020): 492. http://dx.doi.org/10.3390/geosciences10120492.

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Study of the deep structure of the White Sea region is relevant to active geodynamics, manifestations of kimberlite magmatism, and the prospects of oil and gas searches. The aim of this work was to model the velocity and density structure of the earth’s crust in the White Sea region. Modelling was carried out using the known data of instrumental observations and the software complex “Integro”. With the help of 2D models based on deep seismic sounding (DSS) profiles and a digital map of the anomalous gravity field, the density structures of local areas of the region’s crust were refined. A 3D density model was built. Within the framework of this model, the positions of the density layers were determined. The relief of the Mohorovichich (Moho or M) discontinuity reflects the anomalies of the gravity field. Depression of the Moho boundary in the bottleneck of the White Sea indicates the vertical structure of the earth’s crust associated with manifestations of kimberlite magmatism.

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Jia, Cang Qin, Qi Wu Huang e Bai Ru Xia. "Stability Analysis of Soil Slope Using Discontinuity Layout Optimization". Advanced Materials Research 1065-1069 (dicembre 2014): 190–98. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.190.

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Many efforts have been focused on stability problems of geotechnical structures with the limit analysis method. A key advance of this present method is that the problem is described only in terms of nodes and discontinuities connecting those nodes rather than element or bodies. The alternative approximation procedure might involve discretization of a given body using a suitably large number of nodes laid out on a grid, with the failure mechanism comprising the most critical subset of potential discontinuities interconnecting these nodes. The method using Mohr-Coulomb failure criterion to formulate the objective function is developed and the safety factor is determined from optimization. In order to evaluate the applicability and validity of the proposed method numerical results of some examples are presented and compared with the solutions obtained using other well-known techniques. The comparisons show that the proposed method is an effective method and can be applied to evaluate the safety factor in the analyses of slope stability problems.

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