scholarly journals Earthquake forecasting in Italy, before and after Umbria-Marche seismic sequence 1997. A review of the earthquake occurrence modeling at different spatio-temporal-magnitude scales.

2009 ◽  
Vol 51 (2-3) ◽  
Author(s):  
W. Marzocchi
Keyword(s):  
Earthquake Forecasting ◽  
Seismic Sequence ◽  
Earthquake Occurrence ◽  
Magnitude Scales ◽  
Before And After ◽  
Spatio Temporal

Operational Aftershock Forecasting for Mw7.3 Sarpol-e Zahab (2017) Earthquake in Western Iran

2020 ◽  
Author(s):  
Hossein Ebrahimian ◽  
Fatemeh Jalayer ◽  
Hamid Zafarani
Keyword(s):  
Seismic Event ◽  
Border Region ◽  
Earthquake Forecasting ◽  
Model Parameters ◽  
Time Interval ◽  
Seismic Sequence ◽  
Epicentral Area ◽  
Western Iran ◽  
Spatio Temporal ◽  
Robust Reliability

<p><strong>Methodology:</strong></p><p>The implementation of short-term forecasts for emergency response management in the immediate aftermath of a seismic event, and in the presence of an ongoing seismic sequence, requires two basic components: scientific advisories expressed in terms of risk assessment, and protocols that establish how the scientific results can be translated into decisions/actions for risk mitigation. The operational earthquake forecasting framework is geared towards providing scientific advisories in the form of time-dependent probabilities expressing seismicity, hazard and risk that can be practically translated into decisions. Considering the triggered sequence of aftershocks in the process of post-event decision-making and prioritization of emergency operations still seems to need and to deserve much more attention. To this end, the adopted novel and fully-probabilistic procedure succeeds in providing spatio-temporal predictions of aftershock occurrence in a prescribed forecasting time interval (in the order of hours or days). The procedure aims at exploiting the information provided by the ongoing seismic sequence in quasi-real time considering the time needed for registering and transmitting the data. The versatility of the Bayesian inference is exploited to adaptively update the forecasts based on the incoming information as it becomes available. The aftershock clustering in space and time is modelled based on an Epidemic Type Aftershock Sequence (ETAS). One of the main novelties of the proposed procedure is that it considers the uncertainties in the aftershock occurrence model and its model parameters. This is done by moving within a framework of robust reliability assessment which enables the treatment of uncertainties in an integrated manner. Pairing up the Bayesian robust reliability framework and the suitable simulation schemes (Markov Chain Monte Carlo Simulation) provides the possibility of performing the whole forecasting procedure with minimum (or no) need of human interference.</p><p><strong>Application:</strong></p><p>This procedure is demonstrated through a retrospective application to early forecasting of seismicity associated with the 2017 Sarpol-e Zahab seismic sequence activities. On Sunday November 12, 2017, at 18:18:16 UTC, (21:48:16 local time), a strong earthquake with Mw7.3 occurred in western Iran in the border region between Iran and Iraq in vicinity of the Sarpol-e Zahab town. Unfortunately, this catastrophic seismic event caused 572 causalities, thousands of injured and vast amounts of damage to the buildings, houses and infrastructures in the epicentral area. The mainshock of this seismic sequence was felt in the entire western and central provinces of Iran and surrounding areas. The main event was preceded by a foreshock with magnitude 4.5 about 43 minutes before the mainshock that warned the local residence to leave their home and possibly reduced the number of human casualties. More than 2500 aftershocks with magnitude greater than 2.5 have been reported up to January 2019 with the largest registered aftershock of Mw6.4. The fully simulation-based procedure is examined for both Bayesian model updating of ETAS spatio-temporal model and robust operational forecasting of the number of events of interest expected to happen in various time intervals after main events within the sequence. The seismicity is predicted within a confidence interval from the mean estimate.</p>

“Se non scritto, almen dipinto”: The ethos of becoming in Purgatorio 28–33

2021 ◽  
pp. 001458582110225
Author(s):  
Thomas E Peterson
Keyword(s):  
Learning Process ◽  
Perceptual Experience ◽  
The State ◽  
Central Question ◽  
Central Focus ◽  
Cognitive Limitations ◽  
Before And After ◽  
Analogia Entis ◽  
Spatio Temporal ◽  
Divine Beauty

A central question facing the reader of the Paradiso terrestre (Pg 28–33) concerns the selfhood of the protagonist, the character Dante. While the state of Dante’s soul was critical to the poem’s beginning in the dark wood, and remained implicit through the intervening cantos, it is only in the Paradiso terrestre that it becomes the poem’s central focus. This question is explored in cognitive and theological terms in a sequential reading of the six cantos that elucidates the learning process occurring in the character before and after his confession in Pg 31: in his encounter with Matelda, his sensory and perceptual experience of the procession, his dialogues with Beatrice, and his witnessing of her divine beauty as the analogia entis reflecting the beauty of God. The analysis acknowledges the changes in Dante’s style in this interval, which serves as a fulcrum of the entire Commedia, a spatio-temporal threshold in which the transition of one soul, from confession to redemption to instruction on the divine word, is linked to the destiny of humankind and the prospect of universal salvation. Throughout this process of becoming, the character’s cognitive limitations are exposed, not simply as flaws but as signs of his intrinsic humanity.

scholarly journals Dynamics of Erosion and Deposition in a Partially Restored Valley-Bottom Gully

Land ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 62
Author(s):  
Alberto Alfonso-Torreño ◽  
Álvaro Gómez-Gutiérrez ◽  
Susanne Schnabel
Keyword(s):  
High Resolution ◽  
Sediment Deposition ◽  
Aerial Images ◽  
Valley Bottom ◽  
Erosion And Deposition ◽  
Channel Dynamics ◽  
Check Dams ◽  
Before And After ◽  
Multi Temporal ◽  
Spatio Temporal

Gullies are sources and reservoirs of sediments and perform as efficient transfers of runoff and sediments. In recent years, several techniques and technologies emerged to facilitate monitoring of gully dynamics at unprecedented spatial and temporal resolutions. Here we present a detailed study of a valley-bottom gully in a Mediterranean rangeland with a savannah-like vegetation cover that was partially restored in 2017. Restoration activities included check dams (gabion weirs and fascines) and livestock exclosure by fencing. The specific objectives of this work were: (1) to analyze the effectiveness of the restoration activities, (2) to study erosion and deposition dynamics before and after the restoration activities using high-resolution digital elevation models (DEMs), (3) to examine the role of micro-morphology on the observed topographic changes, and (4) to compare the current and recent channel dynamics with previous studies conducted in the same study area through different methods and spatio-temporal scales, quantifying medium-term changes. Topographic changes were estimated using multi-temporal, high-resolution DEMs produced using structure-from-motion (SfM) photogrammetry and aerial images acquired by a fixed-wing unmanned aerial vehicle (UAV). The performance of the restoration activities was satisfactory to control gully erosion. Check dams were effective favoring sediment deposition and reducing lateral bank erosion. Livestock exclosure promoted the stabilization of bank headcuts. The implemented restoration measures increased notably sediment deposition.

scholarly journals Precursory pattern of tidal triggering of earthquakes in six regions of China: the possible relation to the crustal heterogeneity

2013 ◽  
Vol 13 (10) ◽  
pp. 2605-2618 ◽  
Author(s):  
Q. Li ◽  
G.-M. Xu
Keyword(s):  
Earthquake Prediction ◽  
Earthquake Hazard ◽  
Earthquake Forecasting ◽  
Earthquake Occurrence ◽  
Crustal Rocks ◽  
Tidal Triggering ◽  
Crustal Heterogeneity ◽  
Tidal Variations ◽  
Prediction Efficiency

Abstract. We found the possible correlation between the precursory pattern of tidal triggering of earthquakes and the crustal heterogeneities, which is of particular importance to the researchers in earthquake prediction and earthquake hazard prevention. We investigated the connection between the tidal variations and earthquake occurrence in the Liyang, Wunansha, Cangshan, Wenan, Luquan and Yaoan regions of China. Most of the regions show a higher correlation with tidal triggering in several years preceding the large or destructive earthquakes compared to other times, indicating that the tidal triggering may inherently relate to the nucleation of the destructive earthquakes during this time. In addition, the analysis results indicate that the Liyang, Cangshan and Luquan regions, with stronger heterogeneity, show statistically significant effects of tidal triggering preceding the large or destructive earthquakes, while the Wunansha, Wenan and Yaoan regions, with relatively weak heterogeneity, show statistically insignificant effects of it, signifying that the precursory pattern of tidal triggering of earthquakes in these six regions is possibly related to the heterogeneities of the crustal rocks. The above results suggest that when people try to find the potential earthquake hazardous areas or make middle–long-term earthquake forecasting by means of precursory pattern of the tidal triggering, the crustal heterogeneity in these areas has to be taken into consideration for the purpose of increasing the prediction efficiency. If they do not consider the influence of crustal heterogeneity on the tidal triggering of earthquakes, the prediction efficiency might greatly decrease.

scholarly journals RESEARCH ON CONSTRUCTION METHOD OF SPATIO-TEMPORAL DATA MODEL BASED ON BEHAVIOR-EVENT

2020 ◽  
Vol XLII-3/W10 ◽  
pp. 591-594
Author(s):  
J. W. Li ◽  
Y. Ma ◽  
J. W. Jiang ◽  
W. D. Chen ◽  
N. Yu ◽  
...  
Keyword(s):  
Data Model ◽  
Logical Structure ◽  
Physical Structure ◽  
Temporal Data ◽  
Model Based ◽  
Time Space ◽  
Before And After ◽  
Spatio Temporal ◽  
Temporal Objects ◽  
Organic Combination

Abstract. Starting from the object-oriented idea, this paper analyses the existing event-based models and the logical relationship between behavioral cognition and events, and discusses the continuity of behavioral cognition on the time axis from the perspective of temporal and spatial cognition. A geospatial data model based on behavioral-event is proposed. The physical structure and logical structure of the model are mainly designed, and the four-dimensional model of “time, space, attribute and event” is constructed on the axis. The organic combination of the four models can well describe the internal mechanism and rules of geographical objects. The expression of data model based on behavior-event not only elaborates the basic information of geospatial objects, but also records the changes of related events caused by the changes of geographic Entities' behavior, and expresses the relationship between spatial and temporal objects before and after the changes of behavior cognition. This paper also designs an effective method to organize spatio-temporal data, so as to realize the effective management and analysis of spatio-temporal data and meet the requirements of storage, processing and mining of large spatio-temporal data.

Modelling Seismicity in California as a Spatio-Temporal Point Process Using inlabru: Insights for Earthquake Forecasting

2020 ◽  
Author(s):  
Mark Naylor ◽  
Kirsty Bayliss ◽  
Finn Lindgren ◽  
Francesco Serafini ◽  
Ian Main
Keyword(s):  
Point Process ◽  
Spatial Data ◽  
Point Processes ◽  
Earthquake Forecasting ◽  
Data Sets ◽  
Computationally Efficient ◽  
Data Types ◽  
Initial Application ◽  
Spatio Temporal ◽  
Diverse Data

<p>Many earthquake forecasting approaches have developed bespokes codes to model and forecast the spatio-temporal eveolution of seismicity. At the same time, the statistics community have been working on a range of point process modelling codes. For example, motivated by ecological applications, inlabru models spatio-temporal point processes as a log-Gaussian Cox Process and is implemented in R. Here we present an initial implementation of inlabru to model seismicity. This fully Bayesian approach is computationally efficient because it uses a nested Laplace approximation such that posteriors are assumed to be Gaussian so that their means and standard deviations can be deterministically estimated rather than having to be constructed through sampling. Further, building on existing packages in R to handle spatial data, it can construct covariate maprs from diverse data-types, such as fault maps, in an intutitive and simple manner.</p><p>Here we present an initial application to the California earthqauke catalogue to determine the relative performance of different data-sets for describing the spatio-temporal evolution of seismicity.</p>

scholarly journals Analysis of the local lithospheric magnetic activity before and after Panzhihua <i>M</i><sub>w</sub> = 6.0 earthquake (30 August 2008, China)

2011 ◽  
Vol 11 (12) ◽  
pp. 3171-3180 ◽  
Author(s):  
F. Dudkin ◽  
V. Korepanov ◽  
D. Yang ◽  
Q. Li ◽  
O. Leontyeva
Keyword(s):  
Low Frequency ◽  
Magnetic Activity ◽  
Sichuan Province ◽  
Earthquake Forecasting ◽  
Process Data ◽  
Close Proximity ◽  
Before And After ◽  
Short Time ◽  
Signal Sources ◽  
Source Structure

Abstract. Lithospheric ultra low frequency (ULF) magnetic activity is recently considered as a very promising candidate for application to short-time earthquake forecasting. However the intensity of the ULF lithospheric magnetic field is very weak and often masked by much stronger ionospheric and magnetospheric signals. The study of pre-earthquake magnetic activity before the occurrence of a strong earthquake is a very hard problem which consists of the identification and localization of the weak signal sources in earthquake hazardous areas of the Earth's crust. For the separation and localization of such sources, we used a new polarization ellipse technique (Dudkin et al., 2010) to process data acquired from fluxgate magnetometers installed in the Sichuan province, China. Sichuan is the region of the strongest seismic activity on the territory of China. During the last century, about 40 earthquakes with magnitude M ≥ 6.5 happened here in close proximity to heavy populated zones. The Panzhihua earthquake Mw = 6.0 happened in the southern part of Sichuan province on 30 August 2008 at 8:30:52 UT. The earthquake hypocentre was located at 10 km depth. During the period 30–31 August – the beginning of September 2008, many clustered aftershocks with magnitudes of up to 5.6 occurred near the earthquake epicentre. The data from three fluxgate magnetometers (belonged to China magnetometer network and placed near to the clustered earthquakes at a distance of 10–55 km from main shock epicenter) have been processed. The separation between the magnetometers was in the range of 40–65 km. The analysis of a local lithospheric magnetic activity during the period of January–December 2008 and a possible source structure have been presented in this paper.

scholarly journals Arrhythmia Mechanism and Dynamics in a Humanized Mouse Model of Inherited Cardiomyopathy Due to Phospholamban R14del Mutation

Circulation ◽  
2021 ◽  
Author(s):  
Nour Raad ◽  
Philip Bittihn ◽  
Marine Cacheux ◽  
Dongtak Jeong ◽  
Zeki Ilkan ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Ex Vivo ◽  
Regulatory Protein ◽  
Conduction Block ◽  
Adrenergic Stimulation ◽  
Humanized Mouse Model ◽  
Inherited Cardiomyopathy ◽  
Before And After ◽  
Rapid Pacing ◽  
Spatio Temporal

Background: Arginine (Arg) 14 deletion (R14del) in the calcium regulatory protein phospholamban (hPLN R14del ) has been identified as a disease-causing mutation in patients with an inherited cardiomyopathy. Mechanisms underlying the early arrhythmogenic phenotype that predisposes carriers of this mutation to sudden death with no apparent structural remodeling remain unclear. Methods: To address this, we performed high spatio-temporal resolution optical mapping of intact hearts from adult knock-in mice harboring the human PLN WT (WT, N=12) or the heterozygous human PLN R14del mutation (R14del, N=12) before and after ex-vivo challenge with isoproterenol and rapid pacing. Results: Adverse electrophysiological remodeling was evident in the absence of significant structural or hemodynamic changes. R14del hearts exhibited increased arrhythmia susceptibility compared to WT. Underlying this susceptibility was preferential right ventricular (RV) action potential prolongation that was unresponsive to β-adrenergic stimulation. A steep repolarization gradient at the LV/RV interface provided the substrate for inter-ventricular activation delays and ultimately local conduction block during rapid pacing. This was followed by the initiation of macroreentrant circuits supporting the onset of VT. Once sustained, these circuits evolved into high frequency rotors, which in their majority were pinned to the RV. Importantly, these rotors exhibited unique spatio-temporal dynamics that promoted their increased stability in R14del compared to WT hearts. Conclusions: Our findings highlight the crucial role of primary electrical remodeling caused by the hPLNR14del mutation. These inherently arrhythmogenic features form the substrate for adrenergic-mediated VT at early stages of PLN R14del induced cardiomyopathy.

scholarly journals b-value of what? Complex behavior of the magnitude distribution during and within the 2016–2017 central Italy sequence

2022 ◽  
Author(s):  
Marcus Herrmann ◽  
Ester Piegari ◽  
Warner Marzocchi
Keyword(s):  
Relative Rate ◽  
Central Italy ◽  
B Value ◽  
Earthquake Forecasting ◽  
Earthquake Catalog ◽  
Spatiotemporal Variations ◽  
Earthquake Occurrence ◽  
Tectonic Structures ◽  
Magnitude Distribution ◽  
Large Earthquakes

Abstract The Magnitude–Frequency-Distribution (MFD) of earthquakes is typically modeled with the (tapered) Gutenberg–Richter relation. The main parameter of this relation, the b-value, controls the relative rate of small and large earthquakes. Resolving spatiotemporal variations of the b-value is critical to understanding the earthquake occurrence process and improving earthquake forecasting. However, this variation is not well understood. Here we present unexpected MFD variability using a high-resolution earthquake catalog of the 2016–2017 central Italy sequence. Isolation of seismicity clusters reveals that the MFD differs in nearby clusters, varies or remains constant in time depending on the cluster, and features an unexpected b-value increase in the cluster where the largest event will occur. These findings suggest a strong influence of the heterogeneity and complexity of tectonic structures on the MFD. Our findings raise the question of the appropriate spatiotemporal scale for resolving the b-value, which poses a serious obstacle to interpreting and using the MFD in earthquake forecasting.

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