Albania is located in the Alpine fold belt extending to the central part of the Dinarides–Hellenides arc in a zone characterized by intense tectonic-seismic activity that has a considerable influence in shaping the geo-environment of the area. Historically, strong earthquakes occurred in this region and triggered lots of mass movements causing considerable damages such as life loss, destruction of

Spontaneous combustion of coal seams can produce very high temperature (generally between 600 and 850 °C, even reach to 1000 °C), which greatly changes the properties of the surface loess layer, such as its magnetic susceptibility and chromaticity. In order to study a fast, effective and nondestructive method to determine the influence range of coal seam spontaneous combustion zone, and to provide

The downward continuation (DWC) of airborne gravity data usually adopts the Poisson integral equation, which is the first kind Fredholm integral equation. To improve the stability and accuracy of the DWC, based on the traditional regularization methods and Landweber iteration method, we introduce two other iterative algorithms, namely Cimmino and component averaging (CAV). In order to cooperate with

Nowadays, cities and towns all over the world are dotted with high-rise buildings, and floor positioning technology has gradually become the focus of indoor positioning research. Multi-level buildings with an atrium space structure mainly consist of shopping malls and hospital outpatient buildings. This kind of building is widely spread, and they usually have a lot of people and a high demand for location-based

We present our analysis of the characteristics of the waveforms of earthquakes and quarry blasts that occurred within extreme local-distance (< 25 km) of Csókakő (CSKK) station in the Vértes Hills, Hungary. Our motivation was to determine the linear discrimination line between the earthquake and explosion populations. CSKK is located in the Mór Graben, a seismically relatively active region, and also

The service areas of the BeiDou Navigation Satellite System (BDS) are China, the Asia–Pacific, and the world via three stages of development. The BDS constellation is designed to maintain a geostationary Earth orbit (GEO), inclined geosynchronous orbit (IGSO), and medium Earth orbit (MEO). These orbital maneuvers yield certain difficulties for data processing, especially for the BeiDou satellites,

In the present paper, a fuzzy model of assessment is proposed according the framework of fuzzy mathematical theory to estimate the complexity of rock fractures and geological structures. We established the fuzzy evaluation model and decided a trapezoidal membership function using the fuzzy mathematics. Dataset acquisition is integrated with an advanced technique of coupling multiscale fracture data

In double permeability models, the first and second porosities are represented by the main pores and fissures, respectively. The constitutional relation in the models suffers from a disadvantage that the compressibility matrix is symmetric which is incompatible with classic poroelasticity. This study aims to improving the double permeability models not only to well predict the measured velocity and

In the present paper Global Positioning System (GPS) as well as Very Low Frequency (VLF) measurements at multi-stations have been used to analyze ionospheric anomalies related with major earthquake (Mw = 7.4) of South West Banten (Lampung Area), Indonesia. The earthquake occurred on 02 August 2019 at 19:03:21 LT (epicenter at geog. lat = 07.22° S, long. 104.83º E, depth 10 km). Tremors due to the earthquakes

In this study, the amplitudes and Greenwich phase-lags of the principal semidiurnal tides and the diurnal tides of the ocean tide loading displacements (OTLD) were estimated at the worldwide distributed 37 Very Long Baseline Interferometry (VLBI) stations using 36 years of geodetic VLBI observations from 1984 to 2020. Then, the level of agreement was assessed between the OTLD observed by the VLBI space

Understanding the permeability of fractured rocks can make for significant advances in the development of fluid flow and mass transport modeling. This paper investigates the effects of fracture number, length, and aperture on the permeability of fractured rocks with extremely low matrix permeability. For this purpose, we apply numerical estimations of fracture-scale permeability to fractured rock samples

Seismic exploration is an essential way for stratigraphic information acquisition and resource exploitation. However, the unique near surface conditions of the desert region in northwest China pose a special problem. On the one hand, compared with Gaussian noise, desert noise concentrates in the low-frequency band, which is seriously overlapped with those of the effective signals; On the other hand

Gravity Recovery and Climate Experiment (GRACE) and the GRACE-Follow-On (GRACE-FO) gravimetric missions provide essential data for remotely measure large-scale Terrestrial Water Storage (TWS) changes on a regional and global scale. However, during the operating time of the gravimetric missions, monthly or almost yearly data gaps may induce and fail to provide continuous information. Quantifying and

The detection of buried geometrical model parameters is vital to full interpretation of potential field data, especially that related to gravity and/or self-potential anomalies. This study introduced a proposed non-linear least-squares algorithm for solving a combined formula for gravity and self-potential anomalies due to simple geometric shapes. This proposed algorithm was relied upon delimiting

The prediction of an accurate geodetic point velocity has great importance in geosciences. The purpose of this work is to explore the predictive capacity of three artificial neural network (ANN) models in predicting geodetic point velocities. First, the multi-layer perceptron neural network (MLPNN) model was developed with two hidden layers. The generalized regression neural network (GRNN) model was

We present an approximation method for offset curves of polygons on an oblate ellipsoid using implicit algebraic surfaces. The polygon on the ellipsoid is given by a set of vertices, i.e. points on the ellipsoid. The edges are the shortest geodesic paths connecting two consecutive points. The offset curve of the polygon consists of two parts. The offset curve of an edge is the set of points that are

The atomic clock is the core of the Global Navigation Satellite System (GNSS), which plays an important role in Positioning, Navigation and Timing (PNT) services. However, the long-term characteristics of the global BeiDou navigation system (BeiDou-3) and comparison of satellite clocks performance for the five GNSSs have not yet been revealed. We evaluated and analysed the performance of atomic clocks

Before performing the inversion process, the original measured data set is often transformed (corrected, smoothed, Fourier-transformed, interpolated etc.). These preliminary transformations may make the original (statistically independent) noisy measurement data correlated. The noise correlation on transformed data must be taken into account in the parameter fitting procedure (inversion) by proper

A frequency transfer model that is suitable for short baseline links is proposed herein. Based on a GPS single-differenced (SD) observation among two stations, the initial values and the corresponding variance of the SD ambiguity can be estimated. This can form the double-differenced (DD) ambiguity while defining the reference satellite, and can be fixed to an integer value by using the integer search

In order to reveal the residual distribution pattern and obtain a wide range of high-accurate vertical movement field, we systematically analyzed the joint geodetic adjustment with vertical rate parameters (denoted as joint adjustment) issues based on the simulated and actual multi-source vertical data. First of all, 1000 sets of simulated leveling data containing rand noise were constructed and processed

The area of North-East India and Nepal Himalaya undergoes seasonal deformations due to the variation of surface mass loads induced mainly by annual monsoon precipitation. The present study focuses on comparing seasonal horizontal deformations of the Earth’s surface obtained over the area of North-East India and Nepal Himalaya using Global Positioning System (GPS) and the corresponding ones obtained

In subtitle “Tambakrejo SP anomaly, Indonesia”, page 710, for describing Fig. 13 written: “Besides those two faults, the inversion data result also produce four other minor faults with different position (Fig. 13 lower panel)” should be revised as “Besides those two faults, the inversion data result also produce seven other minor faults with different position (Fig. 13 lower panel)”.

Water-bearing structures in front of coal mine shaft drivages require effective advanced prediction. Based on the characteristics of coal field logging curve carrying rich geological information, it is introduced into the advanced prediction of water-bearing bodies in mine shafts. At the same time, mine geophysical prospecting technology, such as the DC resistivity method, can accurately and effectively

Global navigation satellite systems and positioning, navigation, and timing services, such as the newly developed BeiDou satellite system (BDS), require high-accuracy satellite observations. Satellite-induced code bias is present in BDS-2 satellite observations while it is negligibly present in BDS-3 satellite observations. The traditional method of mitigating BDS code bias involves two steps, first

Concentration-number (C-N) fractal modeling technique is adapted and newly proposed to interpret vertical electrical sounding (VES) measurements. This proposed technique is practiced herein on a case study taken from Deir El-Adas, Southern Syria, where four VES geoelectrical profiles (Pro-1, Pro-2, Pro-3, and Pro-4) are interpreted. The general targeting concept of this technique is to use the threshold

Amplification or attenuation of seismic waves while passing through the soil medium can be due to soil type and its stratification or local topographic effects. Such aspects have been theoretically explained in many researches by means of ground response analysis. The results of seismic ground response analysis provide the necessary and realistic information for seismic design of structures and soil-structure

The recent advances in satellite based ionosphere monitoring provided more evidence about earthquake (EQ) precursors from lithosphere ionosphere coupling mechanism. In this paper, we investigate ionospheric anomalies associated with the December 19, 2009, Taiwan EQ (Mw = 6.4), that occurred on UT = 13:02 h. Seismo ionospheric anomalies are evaluated during 31 days (20 day before followed by 10 days

As the gravity formation flying spacecraft jointly developed by National Aeronautics and Space Administration and German Research Centre for Geosciences, the Gravity Recovery and Climate Experiment (GRACE) and GRACE follow-on (GRACE-FO) satellites have adopted the same K-band ranging system and orbit design in order to detect the Earth’s gravity field information. Different from the BlackJack receiver

The North–South Seismic Belt distributed along the eastern margin of the Tibetan Plateau is a regional-scale seismically active zone. The Yuanmou Fault, located at the junction of the North–South Seismic Belt and the Central Yunnan Sub-Block, is an important boundary of earthquakes distribution and topography. Therefore, the studying of the Late Quaternary activity of the Yuanmou Fault is of great

The electrical conductivity and wave velocity of basalt are important parameters for analyzing the evolution of the crust and mantle; they are also used in many fields, such as underground engineering. To analyze the influences of pressure and temperature on the electrical conductivity and wave velocity of basalt, this review summarizes many relevant references. The results show that mineralogical

Fracture or fault can control several geological or geophysical events and exploration, where the fault associated with mineralization or fluid flow can be used as a source for Self-Potential (SP) anomaly. The 2-D inclined sheet can be used for modeling for fault interpretation using SP data. In this paper, the improved crow search algorithm (ICSA) using Levy flight is proposed for SP data inversion

Inter-Satellite Links (ISLs) are intended to improve precision of orbit determination and satellite clock estimation. The ISLs provide a precise pseudorange measurements between satellites in a specific constellation. The study is a preparatory assessment of exploitation of seven connectivity schemes in the terms of the precise orbit determination for three types of constellations—Galileo-like with

A model describing the frequency distribution of geomagnetic field fluctuations has been developed, allowing a better understanding of the influence of the solar magnetic field on the geomagnetic variations. The constructed model is analogous to the one presented by same authors in 2018 to describe the frequency distribution of seismic magnitudes. A similarity between seismic and geomagnetic systems

In the article On the impact of correlations on the congruence test: a bootstrap approach, Table 1 should be corrected to.

Ionospheric peak electron density (NmF2) and total electron content (TEC) are the essential measures of ionospheric variability for modeling their effects on navigation and communication system applications. The global and regional models have their limitations in predicting ionospheric variations at the low latitude Indian region, mainly due to the anomalous electron density gradients and equatorial

The solar flares and geomagnetic storms are considered a potential threat for the upcoming Indian Regional Navigation Satellite System or Navigation with Indian Constellation (NavIC). Therefore, we investigated in detail the occurrence of tracking failure and effects on the positional accuracy of the NavIC L5-band and S-band system under direct exposure of X2.2 and X9.3 solar flare on September 6,

The objective of this paper is to present a new approach for forecasting NAO index (NAOi) based on predictions of sea level anomalies (SLAs). We utilize significant correlations (Pearson’s r up to 0.69) between sea surface height (SSH) calculated for the North Atlantic (15–65°N, basin-wide) and winter Hurrell NAOi, as shown by Esselborn and Eden (Geophys Res Lett 28:3473–3476, 2001). We consider the

To quantitatively understand the geodynamic process of a region, study of geothermal parameters underneath the earth surface is very paramount. Curie depth can be an alternative to delineate geothermal parameters. In the present study, we estimated Curie depths from the power spectra of 25 equally window sizes areas/points with 50% overlap extracted from high-resolution aeromagnetic anomalies of parts

Between February 16 and April 5, 2019, a series of earthquakes took place around the village of Somogyszob, Somogy county, Hungary. The mainshock occurred on March 7 with a local magnitude \(M_L=4.0\) and epicentral intensity of 5 on the EMS scale. The main event was preceded by four foreshocks and followed by four aftershocks. The largest foreshock (\(M_L=2.6\)) was also felt with maximum intensity

Superconducting gravimetry is one main technique to determine the gravity tides. In superconducting gravimeter (SG) measurement, the gravity tides is affected by the gross errors (including spikes and severe deviations and mainly caused by instrument problems and earthquakes) and noise (caused due to the internal structure of SG instrument and measurement environment) in SG data. The singular spectrum

A summary of methods yielding information about the generation and configuration of the geomagnetic main field is presented with special focus on complications concerning these methods. A global source model constructed with the help of machine learning (and deep learning) is proposed to mitigate these issues, in particular the uncertainties caused by vigorous convection and small scale fields.

The revolutionary approach to determining self-noise of the test seismometer by the use of two additional seismometers was presented by Sleeman et al (Bull Seismol Soc Am 96(1):258–271, 2006). Yet nowadays there are common situations where only two seismometers are installed side by side. This article thus outlines the various procedures that can be used in such situations. As it will be shown by examples

Integer ambiguity resolution is critical for achieving positions of high precision and reliability of precise point positioning (PPP). However, as an important error source in global navigation satellite system (GNSS), multipath interference limits the ability of PPP in high-accuracy GNSS positioning applications. Thus, to guarantee the performance of PPP ambiguity resolution techniques in a multipath

This study used the double-difference seismic tomography method to obtain the upper crustal velocity structure in Laizhou Bay and its adjacent areas (LBAA). We found that the horizontal and vertical distributions of the earthquakes after relocation in earthquake swarms are more concentrative than that before relocation. The lateral heterogeneity of crustal velocity structure near the surface in the

China-Pakistan Economic Corridor (CPEC) is the ongoing mega construction project in Pakistan. This project provides multi trading routes like roads, railways and fiber optics to more than 70 countries. Additionally, local infrastructure and industrial zones construction in Pakistan is also the part of this project. This construction needs a considerable amount of construction materials. Therefore,

The detection of deformation is one of the major tasks in surveying engineering. It is meaningful only if the statistical significance of the distortions is correctly investigated, which often underlies a parametric modelization of the object under consideration. So-called regression B-spline approximation can be performed for point clouds of terrestrial laser scanners, allowing the setting of a specific

The height of the development of a caved zone (CZ) and a water-conducting fractured zone (WCFZ), hereinafter “CZ and WCFZ”, in mining of soft coal with a soft mine floor, hard mine roof and different thicknesses of the coal seam, hereinafter “two soft and one hard” unstable coal seam, is of interest in the long wall coal mining. An observation borehole was drilled above a coal seam with an average

Analyzing the partitioning of stress and deformation in active orogenic settings is of fundamental importance for understanding the mechanisms driving the geodynamic evolution and seismicity, particularly in complex orogenic settings. In this respect, a quantitative understanding is obtained by coupling the large-scale geodynamic evolution with partitioning of local deformation and stress patterns

Anomalies in the Radon activity concentration time series recorded in five European caves (Czech Republic, Slovakia, Slovenia) are detected using three hybrid methods: (1) multiple linear regression and autoregressive integrated moving average statistical methods, (2) Empirical Mode Decomposition with Support Vector Regression techniques and (3) the Singular Spectrum Analysis composed with a predicting

This study proposes a model for a BeiDou Satellite Navigation System (BDS) precise timing solution with un-differenced carrier phase observations, and it is suitable for both single-station and multi-station. With this model, not only can users employ high-precision carrier phase observations to improve the uncertainty of the timing service for single station, but they can also directly use the un-differenced

In Biot theory, the relative velocity between fluid and solid and their relative acceleration, via Darcy permeability and the coupling factor, respectively, are used to quantify stress between the phases. In this paper, the relative velocity via variable permeability is used to improve the quantification of the stress. The modeling quantities are the S-wave velocity ratio of brine saturated Berea sandstone

In this paper first, the method used for solving the weighted total least squares is discussed in two cases; (1) The parameter corresponding to the erroneous column in the design matrix is a scalar, model \(({\mathbf{H}} + {\mathbf{G}})^{T} {\mathbf{r}} + \delta \, = {\mathbf{q}} + {\mathbf{e}}\), (2) The parameter corresponding to the erroneous column in the design matrix is a vector, model \(({\mathbf{H}}

Gravity Recovery and Climate Experiment (GRACE) satellite mission had provided gravity data for ca. 15 years, completed its mission in 2017 and handed over to GRACE Follow-On. During its active life, GRACE contributed to the understanding of temporal variations of geoid/quasigeoid heights as well as vertical and horizontal displacements of the Earth’s surface induced by mass loading, and thereby the

In this paper a new method of numerically solving ordinary differential equations is presented. This method is based on the Gaussian numerical integration of different orders. Using two different orders for numerical integration, an adaptive method is derived. Any other numerical solver for ordinary differential equations can be used alongside this method. For instance, Runge–Kutta and Adams–Bashforth–Moulton

The study of climate change is an important field of research. Monitoring of atmospheric variability especially the tropospheric precipitable water vapor (PWV) is a powerful way to investigate climate change. Global navigation satellite systems (GNSS) provide a good tool for studying atmospheric parameters as GNSS signals along its path from the satellites to the ground based receivers suffer a significant

In a non-line-of-sight (NLOS) environment, high accuracy ultra-wideband (UWB) positioning has been one of the hot topics in studying indoor positioning. Aiming at the UWB and inertial measurement unit (IMU) fusion vehicle positioning, a constraint robust iterate extended Kalman filter (CRIEKF) algorithm has been proposed in this paper. It has overcome the innate defect of the extended Kalman filter

The ionospheric anomalies are often responsible for compromising the accuracy and performance of Global Navigation Satellite System (GNSS). GPS Aided Geo Augmented Navigation (GAGAN) is the autonomous Space Based Augmentation System of India which serves to provide timely error detection and correction for the corrupted GNSS signals in aircrafts. This paper discusses a Maximum Minimum Eigen (MME) detector

Investigations of hydraulically induced micro-seismicity are typically connected with magma injections, exploitation of geothermal fields and salt mines. Our study examines the seismicity and seismic sources in a peri-platform region with long salt production history. In addition, a very large site for extraction of aggregates and limestone is presented in the area. Increased seismicity in the region

As a kind of geomagnetic data processing, downward continuation of potential field plays an important role in geologic interpretation and geomagnetic localization. The inherent instability of larger distance downward continuation restricts its practical applications. In this paper, we report a kind of one-step compensation downward continuation method free of iteration using the equivalent wave number