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In the network‐based on‐site earthquake early warning system (EEWS), the 'blind zone', namely the zone where the issued warning arrives later than the destructive S and surface waves, is one of the challenges affecting its effectiveness. The 'blind zone' is determined by the interstation distance, or equivalently the density of seismic stations, of the network. In this paper, we suggest a practical approach according to which, when in a region a temporary increase of seismic hazard is declared, additional stations are deployed in such a way that the blind zone is temporarily reduced. In the procedure, the time‐dependent neo‐deterministic seismic hazard assessment (TD‐NDSHA) plays a vital role in the identification of the regions potentially exposed to high macroseismic intensities. As a showcase example, we consider the scenario of year 2014 at the Sichuan‐Yunnan border of southwest China. The TD‐NDSHA is based on the standard NDSHA procedure at regional scale (bedrock conditions), with the 'controlling earthquakes' defined on the basis of the Annual Consultation. We show that the 'blind zone' can be reduced in the identified areas of interest (e.g., MMI ≥ VI), by deploying a limited number of additional seismic stations. In the case where false alarms can be tolerated, significant reduction of the 'blind zone' can be implemented by moving from a network‐based EEWS to a single‐sensor‐based EEWS and skipping the process of location and magnitude‐determination/prediction procedures. [ABSTRACT FROM AUTHOR]

The Neo Deterministic Seismic Hazard Assessment (NDSHA) is the innovative multi‐disciplinary scenario‐physics‐based approach for the evaluation of seismic hazard and risks. When an earthquake occurs, the ground shaking does not depend on its likelihood according to the widespread Probabilistic Seismic Hazard Analysis (PSHA), which estimates are too often wrong. An "unlikely" earthquake can occur at any time and, sooner or later, with 100% probability. Therefore, from a perspective of safety, it is essential that infrastructure and public installations are designed so as to resist future strong earthquakes. NDSHA has proven to both reliably and realistically simulate comprehensive sets of hazardous ground motions in many regions worldwide. Today NDSHA is gaining momentum in spreading worldwide an innovative Paradigm of Reliable Seismic Hazard Assessment (RSHA) that should ultimately change mind‐sets of scientific and engineering communities from disbelief in probabilistic forecasting to optimistic challenging issues of neo‐deterministic predictability of Natural Hazards and Risks. [ABSTRACT FROM AUTHOR]

While the superficial expression of oceanic ridges is generally symmetric, their deeper roots may be asymmetric. Based on a surface wave tomographic three-dimensional model of the Earth's upper 300 km, we construct a global cross section parallel to the equator of the net rotation of the lithosphere, the so-called tectonic equator. Shear wave velocities indicate a difference between the western and eastern flanks of the three major oceanic rift basins (Pacific, Atlantic, and Indian ridges). In general, the western limbs have a faster velocity and thicker lithosphere relative to the eastern or northeastern one, whereas the upper asthenosphere is faster in the eastern limb than in the western limb. We interpret the difference between the two flanks as the combination of mantle depletion along the oceanic rifts and of the westward migration of the ridges and the lithosphere relative to the mantle. The low-velocity layer in the upper asthenosphere at the depth of 120-200 km is assumed to represent the decoupling between the lithosphere and the underlying mantle. It is also well defined by the distribution of radial anisotropy that reaches minimum values close to the rifts, but with an eastward offset. These results could be explained in the frame of the westward drift of the lithosphere relative to the underlying mantle. doi: 10.1130/G30570.1

The fundamental work of Beno Gutenberg has inspired and guided an appreciable part of research in modern seismology, both from the experimental and the theoretical point of view. Among the several topics of seismology that have benefited from the fundamental contribution of Gutenberg, we consider particularly relevant the description of the asthenospheric low-velocity channel, the definition of the surface waves magnitude and the Gutenberg-Richter law, since they are pivotal tools for seismic hazard assessment. The quite revolutionary model for the lithosphere-asthenosphere system in the European area predicts the existence of almost aseismic lithospheric roots. These roots are located in correspondence of most of the orogenic belts and interrupt the asthenosphere low velocity channel that has been identified by Beno Gutenberg in 1948. The model of the European upper mantle, proposed for the first time in 1979 and subsequently refined, has stimulated a considerable amount of research, which has nicely confirmed the major innovative features of the early model. At present, the subduction of the lithosphere at continent-continent collisions, supported not only by seismological data, is a widely accepted concept within the community of Earth scientists, even if it contradicts one of the basic dogmas of the original formulation of plate tectonics. The proposed model for the Alpine-Apennines area supplies a new and unifying framework for the interpretation of the Quaternary magmatism, at present generally accepted by petrologists and geochemists. The theoretical basis for the Gutenberg's surface-wave magnitude calibration function has been supplied by the use of complete synthetic seismograms, and thus it has been possible to formulate the theoretical [M.sub.s] depth correction. The introduction of the depth correction for [M.sub.S] enables the computation of surface wave magnitude for all earthquakes, regardless of their focal depth. This is especially important for the quantification of subcrustal historical earthquakes, for which the seismic moment may be difficult to estimate from recordings of early mechanical seismographs. The new [M.sub.s] calibrating function yield both distance- and depth-independent magnitude estimates. The analysis of the global seismicity, using the seismotectonic regionalization in subduction zones, mid oceanic ridge zones, island arcs, shows that a single Gutenberg-Richter (GR) relation is not universally applicable and that a multiscale seismicity model can reconcile two apparently conflicting paradigms: the Self-Organized Criticality mechanism and the Characteristic Earthquake concept. The multiscale representation has been applied to Italy, where the zones at the space scale of 400-500 km quite well reproduce the shapes of the regions used to apply the, globally tested, CN intermediate term earthquake prediction algorithm. Keywords: Gutenberg; surface waves; low-velocity channel; earthquake magnitude; b-value; seismic hazard