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Utilizing an updated dataset of 145 GNSS surface velocities, this study examines the fault slip rate and fault geometry along the Main Himalayan Thrust (MHT) in the central Himalaya. Employing a Bayesian inversion model, the present analysis reveals that the upper portion of the MHT ramp exhibits full locking, while the lower flat displays creeping motion. The estimated locking depth and fault depth of MFT range from 4.3 ± 2.6 km to 9.7 ± 2.2 km and 13.5 ± 3.1 km to 15.8 ± 1.9 km, respectively, along the central Himalaya. Further, the slip rate along the transition zone lies in the range of 1.4 ± 0.8 mm/yr to 2.7 ± 0.5 mm/yr. Considering the amount of uncertainties as ~1–2 mm/yr in GNSS velocities, the study suggests that the transition zone along the middle flat of the MHT also exhibits locking behavior. Thus, the estimated locking depth extends to ~15.0 km down-dip and covers a horizontal distance of ~90 km (locking line) on the surface, reaching the foothills of the Higher Himalaya. Furthermore, along the deeper flat of the MHT, the slip rate ranges from 19.4 ± 2.5 mm/yr in the west to 12.8 ± 1.6 mm/yr in the east along Nepal Himalaya. The analysis also calculates the slip deficit rate along the MHT fault plane, revealing values of ~15.1 mm/yr in western Nepal, ~12.7 mm/yr in central Nepal, and ~10.6 mm/yr in eastern Nepal. These slip deficit rates across different segments of central Nepal indicate the potential for large earthquakes in the region. The results are further supported by a resolution test using a checkerboard synthetic model, demonstrating the capability of the GNSS network to capture the slip rate along the MHT. These findings inevitably contribute to a comprehensive assessment of the seismic hazard potential in the central Himalayan region. [ABSTRACT FROM AUTHOR]

Geodetic networks enable us to investigate interseismic crustal deformation along the northwest Himalaya. Using 144 GNSS surface velocities and a Bayesian inversion model, we estimate the slip rate and fault geometry of the Main Himalayan Thrust (MHT) along six arc-normal transects in the northwest Himalaya. We consider that the fault plane consists of three sections along the décollement, namely the locking zone (0−12 km), the transition zone (10−22 km) and the creeping zone (≥22 km). The MHT is found to be completely locked from the surface down to an average depth of 6 ± 2 km. The locking-to-creeping transition zone along the décollement extends from the edge of the fully locked area to a deeper depth (14 ± 3 km) to the tip of the creeping zone of the MHT (17 ± 2 km) with a slip rate of 1.6 ± 0.9 to 3.7 ± 1.1 mm yr−1. Considering the range of uncertainties between 1−2 mm yr−1 for the GNSS velocities, the inverted slip rate along the transition zone of MHT turns out to be insignificant. Thus, the locking zone along the northwest Himalaya extends from the MFT to ∼111 ± 6 km in the north with a locking depth of ∼17 ± 2 km. The deeper part of the MHT is inferred to be creeping with an average slip rate of ∼19.1 ± 1.9 mm yr−1 along the northwest Himalaya. In addition, we have also illustrated a splay-fault model to account for the fault kinematics along the splay faults and the main décollement. The splay-fault model indicates a distributed slip rate at the locking-to-creeping transition zone and about ∼15 per cent smaller slip rate of the MHT than that of the single-fault model. Further, the checkerboard test and the uniform slip model exhibit the reliability of the current GNSS network and the inversion model (single- and splay-fault models). Overall, the updated fault kinematics inevitably contribute to the improvement of seismic hazard evaluation along the northwest Himalaya. [ABSTRACT FROM AUTHOR]

The ability to determine the current state of seismic cycle of large sized earthquakes is of profound importance in societal policymaking and disaster preparation. In this article, we present a probabilistic formulation of event-based natural time counts to develop earthquake potential score (EPS) at 36 cities from northeast India, Bangladesh, and adjoining areas. The time-dependent natural time analysis provides an attractive regional seismic hazard evaluation method, because it (1) exhibits spatiotemporal and clustering invariability, ensuring model consistency, (2) considers "seismic cycles" for a network of faults in a defined area, and (3) enables some physical interpretations aligned with earthquake generation process characterized by stress accumulation and moment release. The modeling results for M ≥ 6 events reveal that EPS values lie between 41 and 94%, with the scores of Agartala (91%), Aizawl (84%), Dimapur (80%), Guwahati (41%), Imphal (90%), Malda (70%), Shillong (52%), Siliguri (73%), Barisal (59%), Chittagong (94%), Comilla (88%), Dhaka (78%), Mymensingh (81%), Narayanganj (77%), Rangpur (55%), and Sylhet (60%). These values essentially serve as a yardstick to statistically assess the current state of regional seismic cycle progression in the study region, bringing out some key information to the decision-makers, engineers, scientists, and citizens to improve earthquake preparedness and mitigation strategies. [ABSTRACT FROM AUTHOR]

Accurate forecasting of renewable energy resources has a deep societal and environmental impact. In this work, we investigate the efficacy and applicability of the Window-Sliding ARIMA (WS-ARIMA) method for daily and weekly forecasting of wind speed. The WS-ARIMA technique with a fixed or variable window length belongs to the class of adaptive models. Particularly, the sliding windows of fixed length are popular in the areas of finance, energy, and traffic management, where the dataset of necessity exhibits a seasonal pattern. To carry out the proposed analysis, the following processes were done: (1) we first perform a stationarity test on the wind speed data and observe weak stationarity; (2) we then apply a grid search method to obtain the optimal parameters of the ARIMA model; (3) we implement the WS-ARIMA method for both daily and weekly wind speed data and compare the results with the conventional ARIMA model, and (4) finally, we perform a residual analysis as a post processing step to examine any systematic bias in the implemented models. The experimental results based on 15 years (2000–2014) of daily and weekly wind speed data collected at four different locations in India reveal that the WS-ARIMA method consistently outperforms the conventional ARIMA method. The inclusion of window sliding in ARIMA has resulted in the overall RMSE reduction up to 75% in daily wind speed data and 50% in the weekly data. Therefore, we recommend the WS-ARIMA model as one of the potential techniques in wind speed forecasting at daily and weekly time horizons. [ABSTRACT FROM AUTHOR]

The collision between Indian and Eurasian tectonic plates results in a series of earthquakes, releasing stored elastic strain accumulated over a long period. This research utilizes 22 new and 26 previously published GPS velocities along with nine years of InSAR observations to estimate high-resolution velocity and strain rate fields across the Kumaun Himalaya. The resulting high-resolution velocity field ranges between 0.5 and 14 mm/yr relative to the India-fixed reference frame. The geodetic strain rate is not uniform across the study region and the higher strain rates are observed along the Main Central Thrust. The areal change rate along the Kumaun Himalaya indicates a significant amount of tectonic compression, with an average value of − 0.08 μstrain ∕ yr , while the maximum shear strain rate in the region has a mean value of 0.08 μstrain ∕ yr. The moment deficit rate, based on accumulated strain and energy release over 200 years, turns out to be 7.59 × 1018 Nm ∕ yr along the Kumaun Himalaya. This suggests that the study region can generate a great earthquake (Mw 8.1) in the future. • High-resolution velocity field estimated by integrating InSAR and GPS observations. • Estimated strain rates are high along the MCT in the Kumaun Himalaya. • The moment deficit rate in the study area is as high as 7.59 × 1018 Nm / yr. • The moment deficit rate suggests an earthquake potential of M w 8.1 in the study area. [ABSTRACT FROM AUTHOR]

In earthquake fault systems, active faults release elastic strain energy in a near-repetitive manner. Earthquake forecasting that basically refers to the assessment of earthquake hazards via probability estimates is crucial for many strategic and engineering planning. As the current need across sciences dominantly grows for conceptualization, abstraction, and application, comparison of lifetime probability distributions or understanding their physical significance becomes a fundamental concern in statistical seismology. Using various characteristic measures derived from density function, hazard rate function, and mean residual life function with its asymptotic (limiting) behavior, the present study examines the similitude of the two most versatile inverse Gaussian and lognormal distributions in earthquake forecasting. We consider three homogeneous and complete seismic catalogs from northeast India, northwest Himalaya, and Kachchh (western India) region for illustration. We employ maximum likelihood and moment methods for parameter estimation, and Fisher information for uncertainty valuation. Using three performance tests based on Akaike information criterion, Kolmogorov-Smirnov criterion, and Anderson-Darling test, we show that the heavy-tailed lognormal distribution performs relatively better in terms of its model fit to the observed data. We envisage that the ubiquitous heavy-tailed property of lognormal distribution helps in capturing desired characteristics of seismicity dynamics, providing better insights to the long-term earthquake forecasting in a seismically active region. [ABSTRACT FROM AUTHOR]

This work concentrates on the distribution of earthquake interevent times in northwest Himalaya and its adjacent regions. We consider 12 time-dependent probability distributions for analysis. The maximum likelihood estimation and Fisher information matrix-based methods are used to estimate model parameters and their respective uncertainties. Results from three model selection criteria suggest that the best fit arises from exponentiated Weibull, exponentiated exponential, Weibull and gamma distributions. An intermediate fit comes from exponentiated Rayleigh, and lognormal distributions, whereas the remaining distributions exhibit a poor fit to the seismic interoccurrence times of present catalogue. Using exponentiated Weibull model, it is observed that the estimated cumulative probability of magnitude 6.0 or higher event in the northwest Himalaya reaches 0.92-0.95 after about 20-23 (2019-2022) years since the last event in 1999. The conditional probability, for an elapsed time of 19 years (i.e. 2018), reaches 0.90-0.95 after about 20-25 (2038-2043) years from now. A series of conditional probability curves is also presented to understand the recent and future earthquake hazard in the study region. This temporal evolution of seismic interevent times may provide important clues to the underlying physical mechanism of earthquake genesis in the northwest Himalaya region. [ABSTRACT FROM AUTHOR]

Despite the extremely complex earthquake generation mechanism in a driven nonlinear threshold system, simple empirical scaling laws apply to the collective behavior of earthquakes in a network of geological faults. The physical interpretation of these properties and associated relations exhibit a wealth of information to study earthquake processes and consequent earthquake hazards in a defined area. In this article, an area-source-based earthquake nowcasting method is implemented to statistically determine the current state of earthquake hazards at several cities of Iran through the formulation of a discrete time-series of cumulative interevent counts, known as natural times. Use of natural times to mark the evolution of the seismic process, rather than the passage of clock time, essentially provides spatiotemporal and clustering invariable properties. Statistical inference of natural time counts corresponding to M ≥ 6.0 events results in an earthquake potential score (%) as Ahvaz (94), Hamadan (50), Isfahan (98), Karaj (76), Kerman (78), Kermanshah (73), Mashhad (40), Qom (92), Rasht (21), Shiraz (98), Tabriz (45), Tehran (78), Urmia (51), and Zahedan (53). These nowcast values provide a snapshot of the current progression of a city in its earthquake cycle of large-sized events and thus facilitate better decision-making, city-planning, and earthquake awareness, leading to an efficient seismic risk reduction strategy in the densely populated study region. • Using natural times, earthquake potential score (EPS) values at 14 cities are computed for Iran. • The EPS values (21%-98%) serve as a yardstick to assess the current progression of earthquake cycle. • Therefore, the study indirectly enables spatial distribution of earthquake risk exposure in Iran. [ABSTRACT FROM AUTHOR]

To determine the spatial distribution of earthquake potential along the active Himalayan arc, we utilize GPS measurements and earthquake data. We derive horizontal velocity field and 2-D strain rates from a new set of 41 regional GPS stations along with 446 published velocities. We convert these strain rate tensors to geodetic moment rate build-up within 24 contiguous segments and compare to the seismic moment rate release derived from a reassessed earthquake catalog of 900 years. The geodetic to seismic moment rate ratio, an indicator of stored strain energy, varies from below unity to more than 50 in different segments. The estimated geodetic moment rate ranges from 1.7 × 1018 Nm/yr to 10.2 × 1018 Nm/yr, whereas the seismic moment rate ranges from 3.7 × 1016 Nm/yr to 5.1 × 1019 Nm/yr. This variation between the geodetic and seismic moment rate corresponds to a moment deficit rate of ~1.15×1017 Nm/yr to 7.97 × 1018 Nm/yr along various segments of the study region. The above moment deficit rate provides an equivalent earthquake potential of magnitude 5.7 − 8.2 in different segments. Specifically, the higher earthquake potential (M w ≥8.0) corresponds to the segments in the central seismic gap and the northeast part of Himalaya, whereas the lower earthquake potential (M w <7.0) corresponds to the segments encompassing the rupture areas of recent large events. The present findings not only provide input constraints on the contemporary crustal deformation but also contributes to the time-dependent seismic hazard analysis along the Himalaya. • We report present-day velocity field along the Himalayafrom 41 new GPS stations along with 446 published velocities. • Geodetic strain rates are observed to be more compressional than tensional along the Himalayan arc. • We compare geodetic moment rate build-up and seismic moment rate release along 24 segments of the study region. • We provide spatial distribution of current earthquake potential along the Himalayan arc. • Our analysis contributes to the time-dependent seismic hazard evaluation in the Himalayan belt. [ABSTRACT FROM AUTHOR]

Throughout history, several large-magnitude earthquakes have caused damage to the Himalayan region and humanity. To understand the present-day strain rate distribution and associated seismic moment budget, a high-resolution velocity field is an essential component. The present study estimates the contemporary seismic moment budget along three spatial sections over the Nepal Himalaya using the state-of-the-art high-resolution velocity field. For this, (1) we integrate 5 years of InSAR data with 77 available GPS observations over the Nepal Himalaya; (2) we then calculate strain rate distribution (dilatational and maximum shear strain rates) from this integrated velocity field, and (3) at last, we compare the geodetic moment accumulation rate estimated from strain rate tensors with the seismic moment release rate based on an earthquake database of 500 years. The results reveal that: (1) the geodetic strain rate is not homogeneous over the Nepal Himalaya, rather along the main central thrust, a relatively higher strain rate is observed; (2) the geodetic moment rate from west to east across three sections ranges from 23.39×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$23.39\times 10^{18}$$\end{document} to 16.59×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$16.59\times 10^{18}$$\end{document} Nm/yr, with the minimum of 8.05×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$8.05\times 10^{18}$$\end{document} Nm/yr in central Nepal, whereas the seismic moment rate varies between 5.02×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$5.02\times 10^{18}$$\end{document} and 11.41×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$11.41\times 10^{18}$$\end{document} Nm/yr, with the minimum of 3.69×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$3.69\times 10^{18}$$\end{document} Nm/yr in central Nepal; (3) the difference between geodetic and seismic moment rates from west to east provides a moment deficit rate of 18.37×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$18.37\times 10^{18}$$\end{document} to 5.18×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$5.18\times 10^{18}$$\end{document} Nm/yr, with the minimum of 4.36×1018\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$4.36\times 10^{18}$$\end{document} Nm/yr in central Nepal, and more importantly, (4) the inferred moment deficit rate suggests that the western and eastern Nepal have an earthquake potential of magnitude Mw\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$M_w$$\end{document} 8.5 and Mw\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$M_w$$\end{document} 8.1, respectively, whereas the central Nepal has energy budget equivalent to an Mw\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$M_w$$\end{document} 7.9 event. In summary, the present study provides spatial distribution of earthquake potential in Nepal Himalaya using the most updated high-resolution InSAR and GPS velocity field, and the findings inevitably contribute to the time-dependent earthquake hazard analysis of the study region. [ABSTRACT FROM AUTHOR]

This study presents a geodetic deformation monitoring approach and its application on two severely affected and uninvestigated study sites in India, namely the Bhurkunda coal mines in Jharkhand, and the Sirobagarh landslide in Rudraprayag, Uttarakhand. For the Bhurkunda site (characterized by underground coal mining related subsidence), a network of 56 GNSS points, densified by Total Station (TS) ground points, was set up during three field visits. GNSS derived deformation estimates reveal that the southern part of the investigated area underwent subsidence (maximum displacement 1.813 m). Furthermore, DEM differences of the three epochs generated using TS points detect a subsidence of 1.358±0.057 m with similar pattern and magnitude of movement as detected by GNSS stations. For the Sirobagarh landslide (witnessing recurring slides due to local geological conditions and rainfall), a GNSS network of six control points in an area of 500×600 m2 was established. Deformation estimates from GNSS show subsidence in the area with a horizontal trend of movement towards the Alaknanda river situated below the landslide (maximum horizontal and vertical displacement values are 0.1306 m and 2.1315 m respectively). Further, for the Sirobagarh landslide, multi-temporal interferometry using Sentinel-1 SAR images detect displacement vectors showing downward movement of the landslide, with displacement rates ranging from 0.008 to −0.115 m yr−1. It is evident that the landslide scarp encountered high magnitude subsidence, whereas the area containing and surrounding the landslide (~30 km2) underwent a moderate rate of subsidence. A set of surveying guidelines for monitoring deformation events of similar kind are discussed. [ABSTRACT FROM AUTHOR]