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We propose a new real‐time approach to detect, locate, and estimate the volume of rockslides by analyzing waveforms acquired from broadband regional seismic networks. The identification of signals generated by rockslides from other sources, such as natural and/or induced earthquakes, is accomplished by exploiting the ratio between local magnitudes (ML) and duration magnitudes (MD). We found that signals associated with rockslides have ML/MD < 0.8, while for earthquakes ML/MD ≅ 1. In addition, we derived an empirical relationship between MD and rockslide volumes, obtaining a preliminary characterization of rockslide volume within seconds after their occurrence. The key points of this study are presented by testing the hypothesis on a recent rockslide event that occurred in northern Italy. We discuss also the potential evolution of the methodology for early warning and/or rapid response purposes.

The Irpinia Seismic Network (ISNet) is deployed in Southern Apennines along the active fault system responsible for the 1980, November 23, MS 6.9 Campania–Lucania earthquake. It is set up by 28 stations and covers an area of about 100 × 70 km2. Each site is equipped with a 1-g full-scale accelerometer and a short period velocimeter. Due to its design characteristics, i.e., the wide dynamic range and the high density of stations, the ISNet network is mainly devoted to estimating in real-time the earthquake location and magnitude from low- to high- magnitude events, and to providing ground-motion parameters values so to get some insights about the ground shaking expected. Moreover, the availability of highquality of data allows studying the source processes related to the seismogenetic structures in the area. The network layout, the data communication system and protocols and the main instrumental features are described in the paper. The data analysis is managed by Earthworm software package that also provides the earthquake location while custom software has been developed for real-time computation of the source parameters and shaking maps. Technical details about these procedures are given in the article. The data collected at the ISNet stations are available upon request

When accompanied by appropriate training and preparedness of a population, Earthquake Early Warning Systems (EEWS) are effective and viable tools for the real-time reduction of societal exposure to seismic events in metropolitan areas. The Italian Accelerometric Network, RAN, which consists of about 500 stations installed over all the active seismic zones, as well as many cities and strategic infrastructures in Italy, has the potential to serve as a nationwide early warning system. In this work, we present a feasibility study for a nationwide EEWS in Italy obtained by the integration of the RAN and the software platform PRobabilistic and Evolutionary early warning SysTem (PRESTo). The performance of the RAN-PRESTo EEWS is first assessed by testing it on real strong motion recordings of 40 of the largest earthquakes that have occurred during the last 10 years in Italy. Furthermore, we extend the analysis to regions that did not experience earthquakes by considering a nationwide grid of synthetic sources capable of generating Gutenberg-Richter sequences corresponding to the one adopted by the seismic hazard map of the Italian territory. Our results indicate that the RAN-PRESTo EEWS could theoretically provide for higher seismic hazard areas reliable alert messages within about 5 to 10 s and maximum lead times of about 25 s. In case of large events (M > 6.5), this amount of lead time would be sufficient for taking basic protective measures (e.g., duck and cover, move away from windows or equipment) in tens to hundreds of municipalities affected by large ground shaking.

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An earthquake early warning (EEW) system is a real‐time seismic monitoring infrastructure that has the capability to provide warnings to target cities before the arrival of the strongest shaking waves. In order to provide a rapid alert when targets are very close to the epicenter of the events, we developed an on‐site EEW approach and evaluated its performance at the Italian national scale. The system is a P wave‐based method that measures in real time two parameters: the initial peak displacement (Pd) and the average period (τc). As output, the system provides the predicted ground‐shaking intensity at the monitored site, the alert level, and a qualitative classification of both earthquake magnitude and source‐to‐receiver distance. We applied the on‐site EEW methodology to a data set of Italian earthquakes, with magnitude ranging from 3.8 to 6, and evaluated the performance of the system in terms of correct warning and lead times (i.e., time available for security actions at the target). The results of this retrospective analysis show that for the large majority of the analyzed cases, the method is able to deliver a correct warning shortly after the P wave detection, with more than 80% of successful intensity predictions at the target site. The lead times increase with distance, with a value of 8–10 s at 50 km and 15–18 s at 100 km.

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