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International audiencehe Boconó Fault system is a major active tectonic feature accommodating an important part of the dextral relative motion between the Caribbean Plate and northern South-America. The main trace follows an axial valley running SW-NE within the Mérida Andes (northwestern Venezuela), and crosscuts a series of moraines related to late Pleistocene glaciers developments and retreats, at an altitude between 2600 and 5000 m. Several lakes were generated after the last retreat (between the Late Glacial Maximum –LGM– and the Younger Dryas re-advance), dammed by lateral and frontal moraines. Among them, the Los Zerpa moraine system yielded rich outcrops ranging from an upstream very coarse torrential to deltaic fill, to a downstream clayey-silty horizontal laminated lacustrine accumulation; a fore-set-type heterogeneous "prograding" body links the two sets. The whole system, as well as the surrounding moraines, underwent successive major earthquakes during the Late Glacial/lower Holocene period as evidenced by co-seismic scarps in the moraines, migrations of the outlet, and associated sagponds. Besides active faulting affecting both the moraines and the sedimentary fill, the latter –main purpose of our detail study– exhibits various evidence of strong disturbances which we relate to seismic shaking, such as: i) successive unconformities with co-seismic slips along fractures in the coarse proximal sediments; ii) successive dip changes, discontinuities, and slumps in the foreset-like set; iii) slumps with basal liquefaction, syn-sedimentary fractures, and instantaneous re-sedimentation in the fine-grained laminated accumulation. Lateral (temporal) correlations are established between the successive disturbances detected in the three situations; in turn, these sedimentary events are correlated with seismic activity of the Boconó Fault main trace. Thus, the whole paleo-lake may be considered as a natural seismograph which worked during several thousands years, after the end of the LGM and during early Holocene

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The effects of both test-panel orientation and exposure angle on the atmospheric corrosion rates of carbon steel probes exposed to a marine atmosphere were investigated. Test samples were exposed in a tree-shape metallic frame with either three exposure angles of 30°, 45° and 60° and orientation north-northeast (N-NE), or eight different orientation angles around a circumference. It was found that the experimental corrosion rates of carbon steel decreased for the specimens exposed with greater exposure angles, whereas the highest corrosion rates were found for those oriented to N-NE due to the influence of the prevailing winds. The obtained data obtained were fitted using the bi-logarithmic law and its variations as to take in account the amounts of pollutants and the time of wetness (TOW) for each particular case with somewhat good agreement, although these models failed when all the effects were considered simultaneously. In this work, we propose a new mathematical model including qualitative variables to account for the effects of both exposure and orientation angles while producing the highest quality fits. The goodness of the fit was used to determine the performance of the mathematical models.