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Scansion is one of the fundamental gestures of criticism and creation. Its exercise coincides with the investigation of discontinuity, that is, with the sensibility to differences. To Antonio Carlos Santos this gesture becomes an operative principle. Thus, between criticism and creation, he elaborates deferment as a method. With it emerges the absent foundation that unites us, distended in the passages between names, times, spaces, affections., A escansão é um dos gestos fundamentais da crítica e da criação. Seu exercício coincide com o apuro da descontinuidade, ou seja, com a sensibilidade para as diferenças. Antonio Carlos Santos faz desse gesto um princípio operatório. Assim, entre a crítica e a criação, elabora o diferimento como um método, com o qual emerge o fundamento ausente que nos une, distendido nas passagens entre nomes, tempos, espaços, afetos.

This paper presents three case studies comprising failure mechanisms in phyllite mine slopes at Quadrilátero Ferrífero, State of Minas Gerais, Brazil. Numerical modeling techniques were used in this study. Failure mechanisms involving discontinuities sub parallel to the main foliation are very common in these mines. Besides, failure through the rock material has also been observed due to the low strength of phyllites in this site. Results of this work permitted to establish unknown geotechnical parameters which have significant influence in failure processes, like the in situ stress field and the discontinuity stiffness. Keywords: Soft rocks, Mine slopes, Numerical modeling, Failure mechanisms

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:30:00Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:37:49Z : No. of bitstreams: 1 2-s2.0-84880262470.pdf: 732876 bytes, checksum: 40851dc9329e41b8821d38f6c30968fc (MD5) Made available in DSpace on 2014-05-27T11:30:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-07-23 Soil degradation can be defined as a process that reduces the ability of soil to produce property or services. Thus, the objective was to study the influence of topography and erodibility in the distribution of the chemical attributes of an Alfissol in degraded areas of Gilbués in the State of Piaui, Brazil. In the chosen area a sampling grid of 1 ha was demarcated, with points spaced at 10 x 10 m, and 121 samples were collected at intersections, in 0-0.20 m depth. Each point was georeferenced as a way to demarcate the area and prepare a topography map. For all samples pH, organic matter, phosphorus, potassium, calcium, magnesium, hydrogen and aluminum were determined. The estimate of erodibility was calculated from the equation proposed by Denardin. Based on the experiment and the results obtained it is concluded that the number of samples used was sufficient to determine the variability of soil in degraded areas of the Gilbués municipality. The discontinuity in the topography of the landscape and erodibility cause a moderate degree of heterogeneity in most chemical properties of the studied soil, establishing specific management zones. Universidade Federal Do Piauí Centro de Ciências da Natureza Laboratório de Análises de Combustíveis - LAPETRO, Avenida Ininga, s/n, Ininga, CEP 64049-550, Teresina-PI Universidade Federal Do Piauí Centro de Ciências Agrárias Departamento de Engenharia Agrícola e Solos, CEP 64049-500, Teresina-PI Universidade Estadual Do Piauí, Prof. Joaquina Nogueira Oliveira, s/n, Aeroporto, CEP 64980-000, Corrente-PI Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castelane, s/n, CEP 14884-900, Jaboticabal-SP Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castelane, s/n, CEP 14884-900, Jaboticabal-SP

In this study, we focus on the region between Gorringe Bank and the Horseshoe Fault located in the SW Iberia margin, which is believed to be the site of the great 1755 earthquake. We model ground motions using an extended source located near the Horseshoe scarp to generate synthetic waveforms using a wave propagation code, based on the finite-difference method. We compare the simulated waveforms, for the Algarve Basin and the Lower Tagus Valley Basin (Portugal), using a 3-D velocity model down to the Moho discontinuity with a simple 1-D layered model. The radiated wave field is very sensitive to the velocity model and a small number of source parameters, in particular, the rupture directivity. The rupture directivity, the strike direction and the fault dimensions are critical to the azimuthal distribution of the maximum amplitude oscillations. We show that the use of a stratified 1-D model is inappropriate in SW Iberia, where sources are located in the oceanic domain and receivers in the continental domain. The crustal structure varies dramatically along the ray paths, with large-scale heterogeneities of low or high velocities. Moreover, combined with the geometric limitations inherent to the region, a strong trade-off between several parameters is often observed; this is particularly critical when studying moderate magnitude earthquakes (M < 6), which constitute the bulk of the seismic catalogue in SW Iberia.