scholarly journals SOURCE PARAMETERS of CRIMEAN-BLACK SEA EARTHQUAKES in 2015

2021 ◽  
pp. 226-236
Author(s):  
B. Pustovitenko ◽  
E. Eredzhepov
Keyword(s):  
Seismic Waves ◽  
Source Parameters ◽  
Normal Fault ◽  
Dislocation Model ◽  
Average Value ◽  
Velocity Models ◽  
Amplitude Spectra ◽  
Tensile Forces ◽  
Dynamic Source

The spectral and dynamic source parameters (М0, r0, , , ησ, , u, Eu and Mw) of 16 Crimean earthquakes with КП=6.5–10.8, restored by amplitude spectra of compression and shear seismic waves recorded by digital regional seismic stations are analyzed. Approximation of the spectra and source parameters calculation is performed in the framework of the Brune dislocation model. The highest values of dynamic parameters (М0, r0, , , ησ, u, EU и Mw) are obtained for the earthquakes on June 13 and August 16 with h=11 km, h=7 km respectively and КП=10.8, which occurred in the Azov-Kuban and Kerch-Anapa areas. The radiation friction r for all earthquakes had a negative value, pointing to a complex slide of the rupture in the source. Within the whole energy range, the average value of the released stress did not exceed Δσ=8∙105 PA (8 bar) and apparent stress ησ <11∙105 PA (11 bar). For most 2015 earthquakes, the average M0 и r0 values were within the confidence intervals of long-term dependencies M0(КП), r0(КП). The values of r0 were evenly distributed concerning the regression r0(КП) and М0 is mostly located below the average according to М0 (КП). The maximum deviations of M0 from the long-term М0(КП) dependence were obtained for the most strong earthquakes on June 13 and August 16 with КП=10.8. These deviations can be associated with participation in average M0 of the "Sevastopol" station data which give low values of М0 and possible errors in determining the focal depths influencing the choice of environment velocity models to calculate М0. For the most strong earthquake of August 16 with Мw=3.8, which occurred in the Kerch-Anapa region, a solution of focal mechanism was obtained. The earthquake occurred under the action of horizontal latitudinal tensile forces. The type of movement in the source is an oblique normal fault. Both nodal planes have near-meridional (STKNP1=167°) and near-diagonal (STKNP2=336°) strike.

scholarly journals SPECTRAL and SOURCE PARAMETERS of CRIMEAN-BLACK SEA EARTHQUAKES

2020 ◽  
pp. 250-262
Author(s):  
B. Pustovitenko ◽  
E. Eredzhepov
Keyword(s):  
Black Sea ◽  
Stress Drop ◽  
Seismic Waves ◽  
Source Parameters ◽  
Normal Component ◽  
Strike Slip ◽  
The Black Sea ◽  
Dislocation Model ◽  
Tensile Forces ◽  
The Individual

The spectral and dynamic source parameters (М0, r0, , , ησ, , ū, Eu and Mw) of 13 Crimean earthquakes with КП = 7.2–11.2 (Mw=2.6–4.1), restored by 123 amplitude spectra of longitudinal and transverse seismic waves recorded by digital regional seismic stations is shown. Approximation of the spectra and the source dynamic parameters calculation based on their parameters is performed in the framework of the Brune dislocation model. Four to seven station definitions participated in the averaging of focal parameters, which ensured a small standard deviation, the scattering degree index of the individual estimates. The best convergence of the station definitions is obtained for the radius of a circular dislocation. The highest values of dynamic para-meters have been obtained for the perceptible earthquake on March 2 with КП=11.2, and the lowest values have been obtained for its weak aftershock on April 6 with КП = 7.2. Within the total range of energies the value of the stress drop does not exceed = 106Pa(10 bar), and the apparent stress drop does not exceed ησ<3∙105Pa (3 bar). The average values of seismic moments and circular dislocation radius within the errors of their deter-mination match the average long-term correlations of the parameters on the earthquake energy level obtained by the analog recording.For the strongest earthquakes on March 2 with Mwreg=4.1 and October 18 with Mwreg=3.8 solutions of the focal mechanisms were obtained. The March 2 earthquake occurred in the central part of the region near the South Coast of Crimea under the action of horizontal tensile forces oriented near the latitude. The type of movement in the focus is a obligue slip with predominance of a normal component over a strike-slip. The earthquake on October 18 occurred in the central part of the Black Sea basin in condition of sublatitudinal compression and submeridional extension. Type of movement in the source is a pure strike-slip. For the main shock on March 2 and its six aftershocks, energy spectra according to the data of Alushta station and their main parameters are given. The analysis of obtained results is given.

scholarly journals Moment tensor inversion of early instrumental data: application to the 1917 High Tiber Valley, Monterchi earthquake

2016 ◽  
Vol 59 (3) ◽  
Author(s):  
Fabrizio Bernardi ◽  
Maria Grazia Ciaccio ◽  
Barbara Palombo ◽  
Graziano Ferrari
Keyword(s):  
Focal Mechanism ◽  
Moment Tensor ◽  
Source Parameters ◽  
Normal Fault ◽  
Historical Earthquakes ◽  
Moment Magnitude ◽  
Macroseismic Data ◽  
Natural Period ◽  
Amplitude Spectra ◽  
Tiber Valley

<p>In this paper we present a new study on the High Tiber Valley earthquake occurred on April 26, 1917. Using the digitized data from mechanical seismograph records, we computed the source parameters like focal mechanism and moment magnitude from moment tensor (MT). The study of historical earthquakes from an instrumental perspective is crucial because of the complexity of problems associated with the study of seismograms of moderate to large earthquakes occurred from the late 19th century until the early 1960s. Since historical earthquake records show significant uncertainties in phase arrival times and have been recorded by seismograph generally with short natural period, we developed a code to compute the MT based on a forward modeling technique, which uses the amplitude spectra of the full waveform length and the first P-arrival polarities to constrain the P- and T-axes. The best solution is determined by the best fit between the observed and synthetic amplitude spectra and from the coherency between the observed and the theoretical first P-arrival polarities. The 1917 High Tiber Valley earthquake is one of the most important 20th century earthquake occurred in the Italian Peninsula for which the focal mechanism and moment magnitude from seismic records are not available. Additionally, we apply a multidisciplinary approach to characterize the source of this earthquake, combining instrumental, macroseismic, geological and tectonic data and investigations. The computed MT results in a north-south normal fault mechanism (strike: 147°, dip: 29°, slip: −94°), which is consistent with the strike estimated from the macroseismic data (157°). The moment magnitude calculated from the MT and that derived from the macroseismic data are M<span><sub>w</sub></span>=5.5±0.2 and M<span><sub>w</sub></span>=5.9±0.1, respectively.</p>

scholarly journals SOURCE PARAMETERS of CRIMEAN-BLACK SEA REGION EARTHQUAKES

2019 ◽  
pp. 299-310 ◽  
Author(s):  
B. Pustovitenko ◽  
I. Kalinyuk
Keyword(s):  
Energy Level ◽  
Black Sea ◽  
Experimental Error ◽  
Source Parameters ◽  
Body Waves ◽  
Dynamic Parameters ◽  
Black Sea Region ◽  
Amplitude Spectra ◽  
The Crimea

The source dynamic parameters of 12 earthquakes in Crimea with energy classes КП=7.0–10.1 have been restored by 63 amplitude spectra of P and S body waves registered by a group of regional seismic stations of the Crimea. For the three strongest earthquakes: May 1, October 15, and December 9, the solution of the focal mechanism has been obtained and the direction of radiation from the source at the registration station has been determined to take into account in the calculation of the scalar seismic moment. For these earthquakes, the best convergence of station definitions of all source dynamic parameters has been obtained. The average values of seismic moments and radii of circular dislocation within the experimental error of their determination satisfy the average long-term dependencies of the parameters on the energy level of earthquakes ob-tained previously by analog records

Evaluation attempt of own body sensing amongst persons with and without scoliosis

2021 ◽  
pp. 1-6
Author(s):  
Elżbieta Szczygieł ◽  
Agata Gigoń ◽  
Izabela Cebula Chudyba ◽  
Golec Joanna ◽  
Golec Edward
Keyword(s):  
Idiopathic Scoliosis ◽  
Sensory Integration ◽  
Head Position ◽  
Clinical Test ◽  
Spine Deformity ◽  
Functional Tests ◽  
Body Proportion ◽  
Average Value ◽  
Age Range

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a common structural spine deformity affecting 2%–4% of adolescents. Due to the unknown cause of idiopathic scoliosis, its therapy is a long-term and often unsatisfactory process. In the literature, it is often suggested that problems related to the feeling of one’s own body are caused by AIS. OBJECTIVE: The aim of this study was to assess the feeling of one’s own body among children with and without scoliosis on the example of feeling the head position, pelvis shape and balance. METHOD: The research included 62 children: 30 with scoliosis and 25 without diagnosed scoliosis with an age range between 11 to 19 years. The minimum scoliosis value was 7∘ and the maximum was 53∘. The average value was 25∘. During the study, three functional tests were used: Cervical Joint Position Error Test (CJPET), Clinical Test of Sensory Integration on Balance (CTSIB) and Body proportion demonstration test (BPDT). RESULTS: The results of the tests showed statistically significant differences (CJPET p= 3.54* 10-14, CTSIB p= 0.0376, BPDT p= 0.0127). However, none of the studies showed a correlation between the results of people with scoliosis and the value of their Cobb angles.

Present-day orogenic processes in the western Kalpin nappe explored by interseismic GNSS measurements and coseismic InSAR observations of the 2020 Mw 6.1 Kalpin event

2021 ◽  
Author(s):  
Ping He ◽  
Yangmao Wen ◽  
Shuiping Li ◽  
Kaihua Ding ◽  
Zhicai Li ◽  
...  
Keyword(s):  
Source Parameters ◽  
Satellite System ◽  
Tien Shan ◽  
Dislocation Model ◽  
Maximum Displacement ◽  
Finite Fault ◽  
Instantaneous Deformation ◽  
Gnss Measurements ◽  
Global Navigation Satellite ◽  
Finite Fault Model

Summary As the largest and most active intracontinental orogenic belt on Earth, the Tien Shan (TS) is a natural laboratory for understanding the Cenozoic orogenic processes driven by the India-Asia collision. On 19 January 2020, a Mw 6.1 event stuck the Kalpin region, where the southern frontal TS interacts with the Tarim basin. To probe the local ongoing orogenic processes and potential seismic hazard in the Kalpin region, both interseismic and instantaneous deformation derived from geodetic observations are employed in this study. With the constraint of interseismic global navigation satellite system (GNSS) velocities, we estimate the décollement plane parameters of the western Kalpin nappe based on a two-dimensional dislocation model, and the results suggest that the décollement plane is nearly subhorizontal with a dip of ∼3° at a depth of 24 km. Then, we collect both Sentinel-1 and ALOS-2 satellite images to capture the coseismic displacements caused by the 2020 Kalpin event, and the interferometric synthetic aperture radar (InSAR) images show a maximum displacement of 7 cm in the line of sight near the epicentral region. With these coseismic displacement measurements, we invert the source parameters of this event using a finite-fault model. We determine the optimal source mechanism in which the fault geometry is dominated by thrust faulting with an E–W strike of 275° and a northward dip of 11.2°, and the main rupture slip is concentrated within an area 28.0 km in length and${\rm{\,\,}}$10.3 km in width, with a maximum slip of 0.3 m at a depth of 6–8 km. The total released moment of our preferred distributed slip model yields a geodetic moment of 1.59 × 1018 N$\cdot $m, equivalent to Mw 6.1. The contrast of the décollement plane depth from interseismic GNSS and the rupture depth from coseismic InSAR suggests that a compression still exists in the Kalpin nappe forefront, which is prone to frequent moderate events and may be at risk of a much more dangerous earthquake.

scholarly journals The waveform inversion of mainshock and aftershock data of the 2006 M6.3 Yogyakarta earthquake

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hijrah Saputra ◽  
Wahyudi Wahyudi ◽  
Iman Suardi ◽  
Ade Anggraini ◽  
Wiwit Suryanto
Keyword(s):  
Joint Inversion ◽  
Body Wave ◽  
Moment Tensor ◽  
Near Field ◽  
Source Parameters ◽  
Waveform Inversion ◽  
Moment Tensor Inversion ◽  
Slip Distribution ◽  
Aftershock Distribution ◽  
Velocity Models

AbstractThis study comprehensively investigates the source mechanisms associated with the mainshock and aftershocks of the Mw = 6.3 Yogyakarta earthquake which occurred on May 27, 2006. The process involved using moment tensor inversion to determine the fault plane parameters and joint inversion which were further applied to understand the spatial and temporal slip distributions during the earthquake. Moreover, coseismal slip distribution was overlaid with the relocated aftershock distribution to determine the stress field variations around the tectonic area. Meanwhile, the moment tensor inversion made use of near-field data and its Green’s function was calculated using the extended reflectivity method while the joint inversion used near-field and teleseismic body wave data which were computed using the Kikuchi and Kanamori methods. These data were filtered through a trial-and-error method using a bandpass filter with frequency pairs and velocity models from several previous studies. Furthermore, the Akaike Bayesian Information Criterion (ABIC) method was applied to obtain more stable inversion results and different fault types were discovered. Strike–slip and dip-normal were recorded for the mainshock and similar types were recorded for the 8th aftershock while the 9th and 16th June were strike slips. However, the fault slip distribution from the joint inversion showed two asperities. The maximum slip was 0.78 m with the first asperity observed at 10 km south/north of the mainshock hypocenter. The source parameters discovered include total seismic moment M0 = 0.4311E + 19 (Nm) or Mw = 6.4 with a depth of 12 km and a duration of 28 s. The slip distribution overlaid with the aftershock distribution showed the tendency of the aftershock to occur around the asperities zone while a normal oblique focus mechanism was found using the joint inversion.

The effects of direct drilling, shallow cultivation and ploughing on some soil physical properties in a long-term experiment on spring barley

1985 ◽  
Vol 104 (1) ◽  
pp. 125-133 ◽  
Author(s):  
K. Chaney ◽  
D. R. Hodgson ◽  
M. A. Braim
Keyword(s):  
Spring Barley ◽  
The Other ◽  
Clay Loam ◽  
Average Value ◽  
Structural Problems ◽  
Physical Measurements ◽  
Long Term Experiment ◽  
Direct Drilling ◽  
Air Capacity

SummaryPhysical measurements were made on the soil of a long-term cultivation experiment comparing direct drilling, tine cultivation and mouldboard ploughing for spring barley to investigate possible reasons for differences in yield. The soil was a typical argillio brown earth, approximately 90 cm of sandy clay loam topsoil and clay loam subsoil overlying magnesian limestone. For the three periods 1971–4, 1975–7 and 1978–80 the mean grain yields were marginally lower after direct drilling than after shallow cultivation or ploughing. There was an average decline in yield of 1·33 t/ha from the first to the last period, the decline being greater for direct drilling than the other two tillage systems. Although the surface horizon (0–5 cm) of direct-drilled soil had a higher content of organic matter than the ploughed, this did not increase the stability of the aggregates. Slaking tests had shown the soil to be inherently unstable and likely to suffer from structural problems. After the first 3 years bulk density of direct-drilled soil (0–15 cm) increased markedly to ca. l·5 g/cm8 and then remained relatively stable. In the ploughed soil, density increased steadily over the period to an average value of co. 1·45 g/cm8. Tine cultivation to 7–8 cm reduced cone resistance values in the surface compared with direct-drilled soil but below 15 cm there were no significant differences. Ploughing gave significantly lower values than direct drilling to a depth of 30 cm. Measurements of pore sizes in direct-drilled and ploughed soil were highly variable with few significant differences. Mean air capacity values (1978–80) tended to be lower in direct-drilled than in ploughed topsoil particularly for plots direct drilled after 7 years of deep tine cultivation. A limited number of root measurements in 1978 and 1980 showed that the length of root per unit of ground area was much less after direct drilling than after ploughing. Shallow cultivation, surprisingly, gave most root with a greater proportion of the root system below 20 cm than in the other two treatments. The classification of this soil according to its suitability for direct drilling cereals is discussed.

scholarly journals Values of rainfall erosivity factor for the Czech Republic

2013 ◽  
Vol 61 (2) ◽  
pp. 97-102 ◽  
Author(s):  
Miloslav Janeček ◽  
Vít Květoň ◽  
Eliška Kubátová ◽  
Dominika Kobzová ◽  
Michaela Vošmerová ◽  
...  
Keyword(s):  
Czech Republic ◽  
Water Erosion ◽  
Rainfall Erosivity ◽  
The Czech Republic ◽  
Average Value ◽  
R Factor ◽  
The Usa ◽  
Time Division ◽  
R Factors

Abstract The processing of ombrographic data from 29 meteorological stations of the Czech Hydrometeorological Institute (CHMI), according to the terms of the Universal Soil Loss Equation for calculating long term loss of soil through water erosion, erosion hazard rains and their occurrence have been selected, with their relative amount and erosiveness - R-Factors determined for each month and years. By comparing the value of the time division of the R-Factor in the area of the Czech Republic and in selected areas of the USA it has been demonstrated that this division may be applied in the conditions of the Czech Republic. For the Czech Republic it is recommended to use the average value R = 40 based on the original evaluation.

scholarly journals Lithospheric structure models applied for locating the Romanian seismic events

1994 ◽  
Vol 37 (3) ◽  
Author(s):  
M. Rizescu ◽  
E. Popescu ◽  
V. Oancea ◽  
D. Enescu
Keyword(s):  
Constant Velocity ◽  
Seismic Waves ◽  
Seismic Events ◽  
Lithospheric Structure ◽  
Structural Units ◽  
Data Set ◽  
Velocity Models ◽  
Seismic Sequences ◽  
Geological Information ◽  
Propagation Velocities

The paper presents our attempts made for improving the locations obtained for local seismic events, using refined lithospheric structure models. The location program (based on Geiger method) supposes a known model. The program is run for some seismic sequences which occurred in different regions, on the Romanian territory, using for each of the sequences three velocity models: 1) 7 layers of constant velocity of seismic waves, as an average structure of the lithosphere for the whole territory; 2) site dependent structure (below each station), based on geophysical and geological information on the crust; 3) curves deseribing the dependence of propagation velocities with depth in the lithosphere, characterizing the 7 structural units delineated on the Romanian territory. The results obtained using the different velocity models are compared. Station corrections are computed for each data set. Finally, the locations determined for some quarry blasts are compared with the real ones.

scholarly journals Trends of the energy and protein value of hylage from legumes in the Republic of Tatarstan

2021 ◽  
pp. 45-48
Author(s):  
Evgeny Olegovich Krupin ◽  
Marsel Sharipzyanovich Tagirov ◽  
Adelya Ayratovna Askarova
Keyword(s):  
Energy Level ◽  
Nutritional Value ◽  
Raw Materials ◽  
Net Energy ◽  
Average Value ◽  
Plant Raw Materials ◽  
Digestible Protein ◽  
The Republic ◽  
Perennial Legumes

The results of the analysis of the dynamics of energy and protein nutritional value of haylage from perennial legumes harvested from plant raw materials in the territory of the Republic of Tatarstan in the period from 1993 to 2018 are described. The long-term average value of the studied indicator was 9.52 MJ / kg, which is 5.54% higher than the norm. The highest content of exchangeable energy was noted in 1996 - 9.67 MJ / kg, which is 1.58% higher than the long-term average. The lowest content of exchangeable energy was established in 2009 (9.36 MJ / kg). The long-term average value of the net energy level of lactation was 1.96 MJ / kg, which is 9.68% higher than the norm. The maximum was observed in 2017 and amounted to 2.17 MJ / kg, and the minimum - in 2001 (1.65 MJ / kg), when it was 23.97% below the norm. It was found that the average long-term value of the level of digestible protein in haylage was 111.31 g / kg, which is 1.78% higher than the norm. The highest content of digestible protein was found in 2010 (17.21%). The smallest value was recorded a year earlier, in 2009 and amounted to 95.64 g / kg, which, respectively, is lower than the average long-term value and the value of the norm by 14.08 and 12.56%, respectively.

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