Comment on “High-Definition Mapping of the Gutenberg–Richter b-Value and Its Relevance: A Case Study in Italy” by M. Taroni, J. Zhuang, and W. Marzocchi

Taroni et al. (2021) published a statistical framework to reliably estimate the b-value and its uncertainties, with the goal being the interpretation in a seismotectonic context and improving earthquake forecasting capabilities. In this comment, we show that the results presented for the Italian region and the conclusions drawn by the authors, are heavily biased due to quarry-blast events in the Italian earthquake catalog used in the analysis. Without removing this anthropogenic component in the data, a meaningful analysis of the earthquake- size distribution for natural seismicity is, in our opinion, not possible. This comment highlights the need for basic data quality analysis before sophisticated statistical tools are applied to a dataset

The new release of the database of Earthquake Mechanisms of the Mediterranean Area (EMMA Version 2)

We present here the second release of a database, running on MS-Access platform, of the earthquake focal mechanisms of the Mediterranean area, published in the literature. For all of the mechanisms (more than 6000) the published parameters, taken from about 193 papers, have been checked for consistency and if necessary corrected when possible. The MS-Access application also allows the major moment tensor catalogs available for the area to be imported (without checking) and used

Visione notturna: dal cinema muto all’astronomia contemporanea

Visione notturna è uno spettacolo che coniuga cinema, teatro e seminario accademico in un inedito esperimento di comunicazione scientifica. Dopo il debutto al “teatro del cielo” di Arcetri nel 2013, lo spettacolo è stato presentato in osservatori, planetari e festival scientifici in tutta Italia, e recentemente anche al cinema La Compagnia di Firenze.Visione notturna (Night Vision) is a show that mixes movies, drama and academic talks together into an original science communication experiment. After its debut at the “teatro del cielo” (“sky theatre”) in Arcetri in 2013, the show has been invited to many planetariums, observatories and science festivals in Italy, and recently also to the La Compagnia theatre in Florence

Power-Law Time Distribution of Large Earthquakes

We study the statistical properties of time distribution of seimicity in California by means of a new method of analysis, the Diffusion Entropy. We find that the distribution of time intervals between a large earthquake (the main shock of a given seismic sequence) and the next one does not obey Poisson statistics, as assumed by the current models. We prove that this distribution is an inverse power law with an exponent $\mu=2.06 \pm 0.01$. We propose the Long-Range model, reproducing the main properties of the diffusion entropy and describing the seismic triggering mechanisms induced by large earthquakes.Comment: 4 pages, 3 figures. Revised version accepted for publication. Typos corrected, more detailed discussion on the method used, refs added. Phys. Rev. Lett. (2003) in pres

The importance of multi-parametric analysis in long-term submarine gas emission monitoring : the SN4 observatory at the north anatolian fault (marmara sea,turkey)

Peer Reviewe

Comparing different models of aftershock rate decay: the role of catalog incompleteness in the first times after main shock

We evaluated the efficiency of various models in describing the time decay of aftershock rate of 47 simple sequences occurred in California (37) from 1933 to 2004 and in Italy (10) from 1976 to 2004. We compared the models by the corrected Akaike Information Criterion (AICc) and the Bayesian Information Criterion (BIC), both based on the log-likelihood function but also including a penalty term that takes into account the number of independent observations and of free parameters of each model. We compared the performance of different models by varying the starting time Ts and the minimum magnitude threshold Mmin for each sequence. We found that Omori-type models including parameter c are preferable to those not including it, only for short Ts and low Mmin while the latters generally perform better than the formers for Ts longer than a few hours and Mmin larger than the main shock magnitude Mm minus 3 units. This clearly indicates that a value of parameter c different from zero does not represent a general property of aftershock sequences in California and Italy but it is very likely induced in most cases by catalog incompleteness in the first times after the main shock. We also considered other models of aftershock decay proposed in the literature: the Stretched Exponential Law in two forms (including and not including a time shift) and the band Limited Power Law (LPL). We found that such models perform worse than the Modified Omori Model (MOM) and other Omori-type models for the large majority of sequences, although for LPL, the relatively short duration of the analyzed sequences (one year) might also contribute to its poor performance.Comment: 33 pages, 10 figures, 1 tabl

The other side of COVID-19. A cross-sectional study on mental health in a sample of Italian nurses during the second wave

Introduction: The COVID-19 pandemic has led to a drastic increase in the workload of healthcare professionals, particularly nurses, with serious consequences for their psychological well-being. Our study aimed to identify demographic and work-related factors, as well as clinical predictors of post-traumatic stress disorder (PTSD) and generalized anxiety disorder (GAD), in nurses employed during the COVID-19 pandemic. Methods: We carried out a cross-sectional study between December 2020 and April 2021 on nurses employed during the COVID-19 second wave (October - December 2020). We evaluated PTSD and GAD using two validated questionnaires: i) the Impact of Event Scale – Revised (IES-R); and ii) General Anxiety Disorder –7 (GAD-7). Results: Overall, 400 nurses, whose mean age was 34.3 years (SD ± 11.7), were included in the study. Most were female (78.5%), unmarried (58.5%) and employed in the central (61.5%) regions of Italy. A total of 56.8% of all participants had clinical predictors of PTSD, recording a median IES-R score (IQR) of 37.0 (22.0, 51.0) (range 1-84; cut-off >33 for PTSD). Furthermore, 50% of respondents reported moderate-to-severe symptoms consistent with GAD, recording a median GAD-7 score (IQR) of 9.5 (6.0,14.0) (range 0-21; cut-off >10 for GAD). Multivariable analysis showed that moderate-to-severe GAD (aOR = 4.54, 95% CI: 2.93 - 7.05), being employed in the critical care area (aOR = 1.74, 95% CI: 1.01 - 3.00) and being female (aOR= 1.88, 95% CI: 1.09 - 3.22) were significantly associated with the presence of clinical predictors of PTSD. Discussion: The levels of PTSD symptoms and anxiety among nurses were high during the pandemic. PTSD and GAD represent a public health problem that should be addressed in the post-pandemic period. Healthcare organizations need to activate specific support and rehabilitation networks and programs for healthcare professionals employed during the COVID-19 pandemic

An atlas of Mediterranean seismicity

We present a description of the characteristics of the seismic deformation occurring in the Alpine Mediterranean Belt, and outline its association with tectonic and geologic features. We map seismic activity using several catalogues. Hypocentral data are retrieved from the Catalog of the International Seismological Center, the most comprehensive compilation of global data. Earthquake size and source geometry are instead evaluated from catalogs of earthquake mechanisms. These include seismic moment tensor catalogs (mainly the Harvard CMT Catalog, the Euro-Mediterranean Regional Centroid-Moment Tensors – RCMT Catalog and the regional moment tensor determination in the European-Mediterranean area – ETH Catalog) and a recent extensive compilation of solutions available in literature (EMMA) that provides consistency-controlled fault-plane solutions where mechanisms based on waveform fitting are missing. The study area follows the Africa-Eurasia margin from the Central Atlantic to Iran, and it has been divided into several provinces for the sake of presentation and graphic purposes. For each province, a brief geologic and tectonic description complements the outline of the pattern of seismicity, illustrated by several maps. Focal mechanisms are also grouped together to yield average mechanisms and enable synoptic views. A comprehensive bibliography is referenced. A CD-ROM accompanying this issue contains, besides maps, figures and results of local comparisons and summation of moment tensors with easy access via sensible maps, also an updated version of the EMMA focal mechanism database. Rather than an attempt at presenting a comprehensive seismotectonic model of the Mediterranean, this contribution aims to offer a panoramic view of the active tectonics as imaged by seismicity and focal mechanisms. Its scope may be seen as similar to that of an atlas, as a broad reference and a support for more specific studies

The 2015 version of the Italian Parametric Earthquake Catalogue (CPTI15)

The Italian Parametric Earthquake Catalogue (CPTI) represents the most extensive and reliable source of parameters for earthquakes in Italy and surrounding areas. Since its first introduction in 1999, CPTI benefits from the results of the 30-years-long Italian tradition in historical earthquake research that, still today, keeps on providing a wealth of studies and macroseismic data. Such data have been collected, homogenized and made available through several releases of the related macroseismic database (DBMI). In 2016, the fourth release of CPTI and DBMI, has been finalized. They provide the most advanced and updated sets of macroseismic and instrumental data and parameters, and cover the time-span 1000-2014 with earthquakes with maximum intensity I ≥ 5 or magnitude Mw ≥ 4.0. The catalogue lists 4574 events, 70% of which accompa- nied by intensity data points (about 125’000 as a whole). Macroseismic data derive from 185 studies, 54 of them are new with respect to the previous version CPTI11. Parameters related to historical earthquakes are completely re-assessed, and magnitudes from macroseismic data are derived with new intensity-to-Mw relationships. Such relationships are based on the same dataset that contributes updated instrumental magnitudes to the catalogue. Either Mw from moment tensor solutions or proxies calculated with new published conversion relationship are considered. If available, both macroseismic and instrumental parameters are provided, together with a set of “preferred ones”, which consist of a selection between the macroseismic and the instrumental epicentres, and the weighted average of the macroseismic and instrumental magnitudes.PublishedTrieste, Italy3T. Storia Sismica4T. Sismologia, geofisica e geologia per l'ingegneria sismica4IT. Banche dat