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Seasonal horizontal deformations obtained using GPS and GRACE data: case study of North-East India and Nepal Himalaya Acta Geod. Geophys. (IF 0.909) Pub Date : 2021-01-13 Jagat Dwipendra Ray, M. Sithartha Muthu Vijayan, Walyeldeen Godah
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
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Correction to: Model parameter estimation and its uncertainty for 2-D inclined sheet structure in self-potential data using crow search algorithm Acta Geod. Geophys. (IF 0.909) Pub Date : 2021-01-11 Arif Haryono, Sungkono, Reni Agustin, Bagus Jaya Santosa, Amien Widodo, Bramantya Ramadhany
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)”.
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Improvement of seismic velocity model by selective removal of irrelevant velocity variations Acta Geod. Geophys. (IF 0.909) Pub Date : 2021-01-04 Ali Rointan, Mehrdad Soleimani Monfared, Hamid Aghajani
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Experimental study on comprehensive geophysical advanced prediction of water-bearing structure of shaft Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-11-27 Shenglin Li, Pingsong Zhang, Fupeng Hu
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
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One-step correction strategy for BDS-2/BDS-3 satellite observation code bias and multipath delay Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-11-19 Chao Hu, Zhongyuan Wang, Pengwen Rao, Tong Cheng
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
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Geological and structural characterizations of a basaltic environment by vertical electrical soundings and multifractal modeling techniques in Deir El-Adas Area, Yarmouk Basin, Syria Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-11-10 Jamal Asfahani, Walid Al-Fares
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
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Assessing the interaction of seismically loaded adjacent valleys using time-domain approach Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-11-09 Navid Soltani, Hamed Javdanian, Nemat Soltani
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
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Possible ionospheric anomalies associated with the 2009 M w 6.4 Taiwan earthquake from DEMETER and GNSS TEC Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-11-04 Abdur Rafeh Abbasi, Munawar Shah, Arslan Ahmed, Najam Abbas Naqvi
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
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On GPS data quality of GRACE-FO and GRACE satellites: effects of phase center variation and satellite attitude on precise orbit determination Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-10-26 Yaowei Xia, Xin Liu, Jinyun Guo, Zhouming Yang, Linhu Qi, Bing Ji, Xiaotao Chang
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
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The Late Quaternary dip–slip characteristics of the left-lateral strike-slip Yuanmou fault, the southwestern margin of the north–south seismic belt of China Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-10-17 Haifeng Lu, Weisong Zhang
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
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Effects of temperature and pressure on electrical conductivity and wave velocity of basalt: a review Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-10-15 Liu Yang, Qiang Sun, Jianjun Hu, Cunbao Li
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
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Model parameter estimation and its uncertainty for 2-D inclined sheet structure in self-potential data using crow search algorithm Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-10-12 Arif Haryono, Sungkono, Reni Agustin, Bagus Jaya Santosa, Amien Widodo, Bramantya Ramadhany
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
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The application of inter-satellite links connectivity schemes in various satellite navigation systems for orbit and clock corrections determination: simulation study Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-10-09 Tomasz Kur, Tomasz Liwosz, Maciej Kalarus
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
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Frequency distribution model for geomagnetic SYM-H fluctuations Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-09-30 Ewin Sánchez, Pedro Vega-Jorquera
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
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Correction to: On the impact of correlations on the congruence test: a bootstrap approach Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-09-18 Kermarrec Gaël, Kargoll Boris, Alkhatib Hamza
In the article On the impact of correlations on the congruence test: a bootstrap approach, Table 1 should be corrected to.
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Modeling of ionospheric characteristics based on canonical correlation analysis at Bangalore for the year 2017 Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-09-18 Ravi Kiran Pyla, J. R. K. Kumar Dabbakuti, S. G. Prasad Mutchakayala, Sairam Yashoda, Manikanta Alluri
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
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Overview of the influence of X2.2 and X9.3 solar flares on NavIC system Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-09-09 Mehul V. Desai, Shweta N. Shah
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,
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Forecasting the North Atlantic Oscillation index using altimetric sea level anomalies Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-27 Małgorzata Świerczyńska-Chlaściak, Tomasz Niedzielski
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
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Curie depth estimated from high-resolution aeromagnetic data of parts of lower and middle Benue trough (Nigeria) Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-26 Mukaila Abdullahi, Raj Kumar
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
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Source analysis of the March 7, 2019 $$\mathbf {M_L=4.0}$$ M L = 4.0 Somogyszob, Hungary earthquake sequence Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-18 Zoltán Wéber; Barbara Czecze; Bálint Süle; István Bondár
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
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Gravity tides extracted from SSA-denoised superconducting gravity data with the harmonic analysis: a case study at Wuhan station, China Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-13 Wenzong Gao, Jinyun Guo, Maosheng Zhou, Hongjuan Yu, Xiaodong Chen, Bing Ji
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
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Recent progress in identification of the geomagnetic signature of 3D outer core flows Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-14 Lukács Kuslits; István Lemperger; András Horváth; Dávid Koronczay; Viktor Wesztergom
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.
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Estimating ‘noise-floor PSD’ by using two or three collocated seismometers: an alternative approach Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-13 Izidor Tasič
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
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Effectiveness of L1-norm regularization sidereal filtering for precise point positioning Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-11 Liu Yang, Jingxiang Gao, Guobin Chang, Chao Chen
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
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Velocity structure of the upper crust and its correlation with earthquake swarms activity in Laizhou Bay and its adjacent areas, China Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-08-01 Jinchao Shen; Minmin Xu; Shicheng Li; Huiyong Yin
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
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The engineering assessments and potential aggregate analysis of mesozoic carbonates of Kohat Hills Range, KP, Pakistan Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-07-06 Gohar Rehman; Guangcheng Zhang; Maqsood Ur Rahman; Naveed Ur Rahman; Tariq Usman; Muhammad Imraz
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,
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On the impact of correlations on the congruence test: a bootstrap approach Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-07-06 Kermarrec Gaël; Kargoll Boris; Alkhatib Hamza
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
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Determination of caved and water-conducting fractured zones of “two soft and one hard” unstable coal seam Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-06-25 Yang Chen; Shuyun Zhu
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
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Crustal stress partitioning in the complex seismic active areas of Romania Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-06-09 A. Bala; M. Radulian; D. Toma-Danila
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
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Detecting time series anomalies using hybrid methods applied to Radon signals recorded in caves for possible correlation with earthquakes Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-05-28 F. Ambrosino; L. Thinová; M. Briestenský; S. Šebela; C. Sabbarese
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
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A model to obtain timing solution with un-differenced observations suitable for single-station/multi-station, a case study of BDS data Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-05-20 Pengfei Zhang; Rui Tu; Rui Zhang; Junqiang Han; Lihong Fan
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
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Velocity and attenuation of ultrasonic S-wave in Berea sandstone Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-05-11 Guangquan Li
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
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A modified iterative algorithm for the weighted total least squares Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-05-07 Younes Naeimi; Behzad Voosoghi
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}}
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Estimation of physical height changes from GRACE satellite mission data and WGHM over Turkey Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-05-05 Emel Zeray Öztürk; Walyeldeen Godah; Ramazan Alpay Abbak
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
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Numerical solution of ordinary differential equations in geodetic science using adaptive Gauss numerical integration method Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-03-13 Mostafa Kiani Shahvandi
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
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Evaluation of precipitable water vapor variation for east mediterranean using GNSS Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-03-07 Mohamed Darrag; Nadia AbouAly; Abdel-Monem S. Mohamed; Matthias Becker; Mohamed Saleh
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
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Research on the UWB/IMU fusion positioning of mobile vehicle based on motion constraints Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-03-03 Xin Li; Yang Wang
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
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Ionospheric anomaly detection and Indian ionospheric climatology from GAGAN receivers Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-02-17 K. M. Sridhar; M. Sridhar; Swapna Raghunath; D. Venkata Ratnam
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
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Seismic sources and Earth structure in the transition zone between Fore-Balkan unit and Moesian platform, NE Bulgaria Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-02-14 Lilia Dimitrova; Gergana Georgieva; Petya Trifonova; Emil Oinakov; Valentina Protopopova; Metodi Metodiev
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
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One-step compensation downward continuation method free of iteration in wave number domain Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-02-11 Yu Huang; Zhenchuan Lv; Lihua Wu
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
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Self potential data interpretation utilizing the particle swarm method for the finite 2D inclined dike: mineralized zones delineation Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-02-07 Khalid S. Essa
The self potential data interpretation is very important to delineate and trace the mineralized zones in several regions. We study how to interpret self potential anomalies due to a finite two-dimensional inclined dike using the particle swarm algorithm. However, the precise estimation of the model parameters during the inverse solution are unknown. Here, we show that the particle swarm algorithm is
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Desert seismic random noise reduction framework based on improved PSO–SVM Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-31 Mo Li; Yue Li; Ning Wu; Yanan Tian; Teng Wang
As one of the major regions of carbonate rock oil–gas exploration in western China, Tazhong area of the Tarim Basin has severe environment and complex ground surface conditions, hence the signal to noise ratio (SNR) of the field seismic data is extremely low. To improve the SNR of desert seismic data is a crucial step in the following work. However, the random noise in desert seismic characterizes
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Attenuation of regional seismic Lg waves and its spectral characteristics in and around the Indo-Burman Ranges of North Eastern region of India Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-23 Bijit Kumar Choudhury
The propagation characteristics of crustal Lg waves have been investigated in and around geotectonically complex Indo-Burman Ranges (IBR) of North Eastern region (NER) of India. To cater towards seismic hazard assessment and civil engineering practices, Lg attenuation has been studied by determining the regional average quality factor (QLg) in the frequency range of 0.5–5 Hz. The Lg attenuation regional
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Application of adaptive iterative low-rank algorithm based on transform domain in desert seismic signal analysis Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-22 Xiaofu Sun; Yue Li
Elimination of random noise is crucial in seismic data processing. Especially in desert area, field record generally has problems of weak effective reflection wave and strong noise due to its special surface factors. Besides, desert noise has characteristics of low-frequency, non-stationary and non-Gaussian. Thus, it is difficult to separate the effective signal from desert noise in low-frequency band
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Experiment and analysis for the influence of saturating method on saturation exponent n Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-13 Pan Baozhi; Lei Jian; Guo Yuhang; Zhang Lihua; Fan Yufei
Reservoir evaluation of tight sandstone involves the determination of reservoir properties from samples and logs. In the calculation of water saturation, Archie formula is an important fundamental and connection between log evaluation and petrophysics. Highly accurate parameters of Archie formula are the key to the log evaluation of gas-bearing tight sandstone. At present, there are two methods of
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Ambient noise levels in Turkey and an evaluation of recording quality of the National Network Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-04 Mehmet Ozyazicioglu; Lars Ottemöller; Tuğbay Kılıç; Fatih Alver; Ömer Kılıçarslan
By utilizing data from the National Seismic-Monitoring Network of Turkey, operated by AFAD (Disaster and Emergency Management Presidency, Ministry of the Interior), power spectra of 198 stations distributed countrywide are computed and probability density functions as well as diurnal, weekly, monthly and annual spectrogram-graphics, hence, are obtained. Observed noise levels are the result of natural
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Reducing ZHD–ZWD mutual absorption errors for blind ZTD model users Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-03 Maohua Ding
In precise point positioning (PPP), the zenith hydrostatic delay (ZHD) is traditionally treated as a priori value from the ZHD model but the zenith wet delay (ZWD) is treated as an unknown parameter to estimated. For some near real-time PPP tasks, priori ZHD from the blind ZHD models are often used because external meteorological measurement or information about atmospheric pressure or ZHD can not
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A combined estimator using TEC and b -value for large earthquake prediction Acta Geod. Geophys. (IF 0.909) Pub Date : 2020-01-02 Sergio Baselga
Ionospheric anomalies have been shown to occur a few days before several large earthquakes. The published works normally address examples limited in time (a single event or few of them) or space (a particular geographic area), so that a clear method based on these anomalies which consistently yields the place and magnitude of the forthcoming earthquake, anytime and anywhere on earth, has not been presented
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Seismic attribute method for concealed collapse column identification in coal fields Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-12-12 Bin Wu; Junyu Kong; Shouhua Dong
A collapse column is a geological structure formed by the dissolution of a soluble rock layer under certain hydrogeological conditions. This forms a cavity, which is filled by the overburden. Collapse columns have a great impact on coal mining safety. In this work, a model of a concealed collapse column is constructed according to its diameter, and the finite difference method is used to simulate it
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Reciprocal comparison of geodetically sensed and modeled vertical hydrological loading products Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-12-07 Vagner G. Ferreira; Zhiqiang Liu; Henry C. Montecino; Peng Yuan; Caleb I. Kelly; Abubakar S. Mohammed; Lu Y. Han
AbstractThe Global Positioning System (GPS) permanent stations at the equatorial and southern sub-tropical hydrobelts of South America undergo the highest seasonality on the Earth due to hydrological loadings. Fortunately, there are products that account for such variations, although some of them have not been properly evaluated. For instance, global solutions of Gravity Recovery and Climate Experiment
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New technique of electrical soundings: theoretical modeling and experimental application in study of state of the soil dam Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-11-25 Olga Ivanovna Fedorova; Vitaliy Yurievich Gorshkov
The results of mathematical modeling of electrical soundings with the AMNB (Schlumberger, Wenner) arrays and the proposed combined AMN + NMA array above horizontally layered medium and including a ball medium are presented. It is shown that the combined array has two main advantages: the current penetration depth is greater at the same position of outer electrodes of the considered arrays; edge effects
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Future stress accumulation zones around the main active faults by 3D numerical simulation in East Azerbaijan Province, Iran Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-11-13 Pouya Sadeghi-Farshbaf; Mohammad Mahdi Khatib; Hamid Nazari
As a preliminary three-dimensional numerical analysis, this research aims to detect future zones of high-stress accumulation caused by the interaction of active faults within a 3D topographic geological block based on finite-element analysis. Stress analysis of the three-dimensional topographic model covers both static and dynamic loading caused by topographic loads and crustal movements, and can provide
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Paleo-tectonic data evaluating from foundation excavations: a case study Burdur Fault segments (Turkey) Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-11-13 Mehmet Ozcelik
Burdur Fault (BF) is located in Fethiye Burdur Fault Zone and it has formed in three main sections as Gölbaşı–Gökçebağ, Burdur and Yassıgüme–Çendik. The Neogene Basin is a NE–SW oriented depression basin which forms Plio-Quaternary aged lacustrine and alluvial deposits. Paleo-seismic structures on lacustrine sediments were studied with three excavation surfaces at the BF segments in Burdur settlement
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Inverting gravity anomalies over the Burdur sedimentary basin, SW Turkey Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-11-06 Erdinc Oksum; Mustafa Nuri Dolmaz; Luan Thanh Pham
The study area comprises the NE–SW trending Burdur Basin situated at the tectonically active northeastern part of the Fethiye–Burdur Fault Zone (FBFZ), SW Turkey. The basin demonstrates a half graben geometry hosting lacustrine sedimentary deposits from the Late Miocene onward and is bounded by normal faults on its southern side namely the Burdur Fault Zone. In this study, gravity anomalies over the
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An improved prediction algorithm for Earth’s polar motion with considering the retrograde annual and semi-annual wobbles based on least squares and autoregressive model Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-11-06 Zhangzhen Sun; Tianhe Xu; Chunhua Jiang; Yuguo Yang; Nan Jiang
Earth Rotation Parameters (ERP) are indispensable in the transformation between the Celestial Reference Frame and the Terrestrial Reference Frame, and significant for high-precision space navigation and positioning. As a key parameter in ERP, Polar Motion (PM) is of great importance in analyzing and understanding the dynamic interaction between solid Earth, atmosphere, ocean and other geophysical fluids
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A combined EMD and MSSA model for the extraction of gravity tide correction from relative gravimetric data Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-10-24 Jianbo Wang; Jinyun Guo; Hongjuan Yu; Yi Yang; Bing Ji; Yongzhong Ouyang; Guozhen Zha
A combined empirical mode decomposition (EMD) and multichannel singular spectrum analysis (MSSA) model (EMD–MSSA model) was used for extraction of the gravity tide correction without a priori information (e.g., station coordinates) from static relative gravimetric data. Static observational data acquired using a CG-5 relative gravimeter over 16 days were used to investigate the feasibility and reliability
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Selecting data for autoregressive modeling in polar motion prediction Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-10-22 Fei Wu; Guobin Chang; Kazhong Deng; Wuyong Tao
The Least-squares extrapolation of harmonic models and autoregressive (LS + AR) prediction is currently considered to be one of the best prediction model for polar motion parameters. In this method, LS fitting residuals are treated as data to train an AR model. But it is readily known that using too many data will result in learning a badly relevant AR model, implying increasing the model bias. It
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A heuristic singular spectrum analysis method for suspended sediment concentration time series contaminated with multiplicative noise Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-09-23 Fengwei Wang; Yunzhong Shen; Qiujie Chen; Weiwei Li
This paper proposes a heuristic singular spectrum analysis (SSA) approach to extract signals from suspended sediment concentration (SSC) time series contaminated by multiplicative noise, in which multiplicative noise is converted to approximate additive noise by multiplying with the signal estimate of the time series. Therefore both the signal and noise components need to be recursively estimated.
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An improved model for BDS satellite ultra-rapid clock offset prediction based on BDS-2 and BDS-3 combined estimation Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-09-23 Chao Hu; Qianxin Wang; Yanghai Min; Ya Mao; Youxing Gong
Ultra-rapid clock products provide the main parameters for real-time or near real-time precise point positioning services. However, it has been found that BeiDou ultra-rapid clock offsets do not meet the requirements for high-accuracy applications because of their low accuracy, especially regarding the prediction parts. This study proposes an improved model for BDS satellite ultra-rapid clock offset
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An improved method for detecting BeiDou signal-in-space anomalies from precise ephemerides Acta Geod. Geophys. (IF 0.909) Pub Date : 2019-09-10 Lihong Fan; Rui Tu; Rui Zhang; Zengji Zheng; Xiaochun Lu; Jinhai Liu; Xiaodong Huang; Ju Hong
The signal-in-space (SIS) anomalies caused by satellites and control segments can greatly affect the reliability and safety of navigation and positioning users. The prior information associated with the failure of the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) algorithm were obtained by the evaluation of SIS failure rates broadcasted with navigation ephemeris to investigate the integrity
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