scholarly journals SEISMIC MODEL OF THE UPPER EARTH`s CRUST ON NORTH-EAST PART OF TRAVERSE 3-DV BASED ON RESULTS OF HEAD WAVES DIGITAL PROCESSING

2021 ◽  
Vol 2 (2) ◽  
pp. 225-233
Author(s):  
Pavel O. Polyansky ◽  
Alexander F. Emanov ◽  
Alexandr S. Salnikov
Keyword(s):  
Sedimentary Cover ◽  
Mineral Resources ◽  
Digital Processing ◽  
Velocity Model ◽  
Depth Interval ◽  
Tectonic Block ◽  
East Part ◽  
North East ◽  
Head Waves ◽  
Refracted Waves

Digital processing of refracted waves data, which are registered on North-East part of profile3-DV, is done. Time sections and velocity model are formed. It is proved, that refraction horizons on depth interval of 0-1.5 km are geologic boundaries in sedimentary cover on Ayan-Yuryakh tectonic block. Refraction boundary on depth of ~1.0 km is not lithologic border on Inyaly-Debin block. Layers, which are potentially productive for ore mineral resources, are substracted by low values of V/V (1.66-1.70) on depth below 1.0 km, on Inyaly-Debin block and Orotukan-Balygychan elevation.

Upper earth crust’s seismic structure on conjuction zone of Eurasian and Okhotomorskaya plates (according to head waves data)

2020 ◽  
Author(s):  
Pavel O. Polyansky ◽  
◽  
Alexander F. Emanov ◽  
Alexandr S. Salnikov ◽  
◽  
...  
Keyword(s):  
Digital Processing ◽  
Earth’S Crust ◽  
Depth Interval ◽  
Seismic Structure ◽  
Seismic Model ◽  
East Part ◽  
North East ◽  
Head Waves ◽  
Earth's Crust

Digital processing of CDP–data, which are registered on North–East part of profile 3–DV, is done. Time sections which are result from method of head waves dynamic conversion were achieved for tectonic blocks are located at conjuction zone of Eurasian and Okhotomorskaya plates. Coefficients of refraction on the upper Earth’s crust were calculated based on frequencies difference between initial seismic traces and traces–results of processing. Seismic model of 0–2 km depth interval was constructed.

scholarly journals UPPER EARTH CRUST’S REFRACTION HORIZONS ON TRAVERSE 1-SB (TRANSBAIKALIAN PART)

2019 ◽  
Vol 2 (2) ◽  
pp. 11-18
Author(s):  
Pavel Polyansky ◽  
Alexander Emanov ◽  
Alexandr Salnikov
Keyword(s):  
Seismic Data ◽  
Digital Processing ◽  
Crystalline Basement ◽  
Depth Interval ◽  
Upper Crust ◽  
Intrusive Body ◽  
Fold Belt ◽  
Head Waves ◽  
Seismic Sections

Digital processing of seismic data, which are registered on Transbaikalian part of reference geophysical profile 1-SB, is executed. These data are registered on CDP source-receiver configuration. Time sections images and wavefields of P- and S- head waves are result from technique of head waves dynamic conversion. These time sections are image a structure of refraction boundaries on the upper Earth crust on some areas of Argunskaya fold area, Mongol-Okhotsky fold belt, West-Stanovaya and Selengino-Yablonevaya fold areas. Seismic sections of depth interval of 0-2 km are constructed. Boundaries of intrusive body are detected on upper crust of Argunskaya fold area. This body is underlying lens shaped sedimentary layers on depth interval of 0.5÷1.0 km. Top of crystalline basement is established on the depth interval of 1.6-2.0 km on the northern part of Mongol-Okhotsky fold belt.

TBE in Italy

2019 ◽  
Author(s):  
Valentina Tagliapietra ◽  
Flavia Riccardo ◽  
Giovanni Rezza
Keyword(s):  
Case Series ◽  
East Part ◽  
Mountainous Regions ◽  
North East ◽  
The North ◽  
Tick Borne Encephalitis ◽  
Low Incidence

Italy is considered a low incidence country for tick-borne encephalitis (TBE) in Europe. Areas at higher risk for TBE in Italy are geographically clustered in the forested and mountainous regions and provinces in the north east part of the country, as suggested by TBE case series published over the last decade.

SEJNEŃSKI OŚRODEK KOŚCIELNY (WYBRANE ZAGADNIENIA)

2016 ◽  
Vol 10 (2) ◽  
pp. 87-97
Author(s):  
Wojciech W Guzewicz
Keyword(s):  
East Part ◽  
North East ◽  
The North ◽  
Registered Office

Sejny is situated in the north-east part of Poland, in the diocese Elk. Here among othersa parish is located near a sanctuary of NMP hitting and the registered office of the Sejny deanery.It is a city of the borderland, cultures and nations. Presenting landmarks in the life to thecongregation, describing the infrastructure and populations are a purpose of the article, as well asdiscussing the most important punished monuments of this earth.

Far-offset detection of normal modes and diving waves: a case study in Valhall, southern North Sea

Geophysics ◽  
2021 ◽  
pp. 1-50
Author(s):  
Filipe Borges ◽  
Martin Landrø
Keyword(s):  
Normal Modes ◽  
Seismic Source ◽  
Velocity Model ◽  
Seismic Survey ◽  
The Past ◽  
Lack Of Control ◽  
Record Data ◽  
Refracted Waves ◽  
1D Velocity Model

The use of permanent arrays for continuous reservoir monitoring has become a reality in the past decades, with Ekofisk and Valhall being its flagships. One of the possibilities when such solution is available is to passively record data while acquisitions with an active source are ongoing in nearby areas. These recordings might contain ultrafar-offset data (over 30 km), which are hardly used in standard reservoir exploration and monitoring, as they are mostly a combination of normal modes, deep reflections and diving waves. We present here data from the Valhall Life of Field Seismic array, recorded while an active seismic survey was being acquired in Ekofisk, in April 2014. Despite the lack of control on source firing time and position, analysis of the data shows that the normal modes are remarkably clear, overcoming the ambient noise in the field. The normal modes can be well explained by a two-layer acoustic model, while a combination of diving waves and refracted waves can be fairly well reproduced with a regional 1D velocity model. We suggest a method to use the far-offset recordings to monitor changes in the shallow sediments between source and receivers, both with and without a coherent seismic source in the area.

scholarly journals Application of Soft Data in Nodule Resource Estimation

2020 ◽  
Author(s):  
Steinar Løve Ellefmo ◽  
Thomas Kuhn
Keyword(s):  
Conditional Expectation ◽  
Expert Knowledge ◽  
Mineral Resources ◽  
Deep Ocean ◽  
Study Data ◽  
Ocean Floor ◽  
Soft Data ◽  
North East ◽  
The Mean ◽  
Harsh Conditions

AbstractMinerals and metals are of uttermost importance in our society, and mineral resources on and beneath the deep ocean floor represent a huge potential. Deciding whether mining from the deep ocean floor is financially, environmentally and technologically feasible requires information. Due to great depths and harsh conditions, this information is expensive and time and resource consuming to obtain. It is therefore important to use every piece of data in an optimum way. In this study, data retrieved from images and expert knowledge were used to estimate minimum and maximum nodule abundances at image locations from an area in the Clarion-Clipperton-Zone of the equatorial North East Pacific. From the minimum and maximum values, box cores and the spatial correlation quantified through variogram, a conditional expectation and associated uncertainty were obtained through the Gibbs sampler. The conditional expectation and the uncertainty were used with the assumed certain abundance data from the box cores in a kriging exercise to obtain better informed estimates of the block by block abundance. The quality assessment of the estimations was done based on distance criterion and on kriging quality indicators like the slope of regression and the weight of the mean. From the original image locations, alternative image configurations were tested, and it was shown that such alternatives produce better estimates, without extra costs. Future improvements will focus on improving the estimation of the minimum and the maximum values at image locations.

scholarly journals PHENOLIC PROFILE OF HONEYDEW HONEYS FROM THE NORTH-EAST PART OF ROMANIA

2016 ◽  
Vol 73 (2) ◽  
pp. 105
Author(s):  
Mircea OROIAN ◽  
Sorina ROPCIUC ◽  
Amalia BUCULEI ◽  
Sergiu PADURET ◽  
Elena TODOSI
Keyword(s):  
European Union ◽  
Moisture Content ◽  
The European Union ◽  
Free Acidity ◽  
Glucose Content ◽  
Phenolic Profile ◽  
East Part ◽  
North East ◽  
The North ◽  
Acidic Nature

The aim of this study is to determine the physicochemical (moisture content, pH, free acidity, electrical conductivity, colour (L*, a*, b*, chroma, hue angle), ash content, fructose and glucose content) and to determine the phenolic profile (quercetin, apigenin, myricetin, isorhamnetin, kaempherol, caffeic acid, chrysin, galangin, luteolin, p-coumaric acid, gallic acid and pinocembrin) of five samples of honeydew honeys from the North East part of Romania. The honey samples analysed respected the maximum allowable level of the moisture content, which is established by the European Union at 20%. The acidic nature of the honeydew is confirmed by the level of the pH and free acidity of the samples, and is influenced in principal by the organic acids; all the samples had a free acidity lower than 50 meq acid/kg. The honey colour is dark which is confirmed by the level of the CIE L*a*b* parameters (lower values of L*, a* and b*). The inverted sugar level (fructose and glucose content) is higher than 60 g/ 100g, respecting the European Union directive. The phenolic profile of the honeydew samples do not presented one compound that can be considered a chemical marker, the major polyphenols presented into the honeydew honeys are quercetin and pinocembrin.

scholarly journals Geo-dynamic Activity of the Fluvial Flows of North East Part of Kosova

2014 ◽  
Vol 120 ◽  
pp. 711-715
Author(s):  
Shpejtim Bulliqi ◽  
Florim Isufi ◽  
Bashkim Kastrati ◽  
Fitim Humolli
Keyword(s):  
Dynamic Activity ◽  
East Part ◽  
North East

Inversion of seismic refraction and reflection data for building long-wavelength velocity models

Geophysics ◽  
2015 ◽  
Vol 80 (2) ◽  
pp. R81-R93 ◽  
Author(s):  
Haiyang Wang ◽  
Satish C. Singh ◽  
Francois Audebert ◽  
Henri Calandra
Keyword(s):  
Wave Equation ◽  
Short Wavelength ◽  
Velocity Model ◽  
Density Model ◽  
Data Set ◽  
Reflected Waves ◽  
Long Wavelength ◽  
Velocity Models ◽  
Computation Efficiency ◽  
Refracted Waves

Long-wavelength velocity model building is a nonlinear process. It has traditionally been achieved without appealing to wave-equation-based approaches for combined refracted and reflected waves. We developed a cascaded wave-equation tomography method in the data domain, taking advantage of the information contained in the reflected and refracted waves. The objective function was the traveltime residual that maximized the crosscorrelation function between real and synthetic data. To alleviate the nonlinearity of the inversion problem, refracted waves were initially used to provide vertical constraints on the velocity model, and reflected waves were then included to provide lateral constraints. The use of reflected waves required scale separation. We separated the long- and short-wavelength subsurface structures into velocity and density models, respectively. The velocity model update was restricted to long wavelengths during the wave-equation tomography, whereas the density model was used to absorb all the short-wavelength impedance contrasts. To improve the computation efficiency, the density model was converted into the zero-offset traveltime domain, where it was invariant to changes of the long-wavelength velocity model. After the wave-equation tomography has derived an optimized long-wavelength velocity model, full-waveform inversion was used to invert all the data to retrieve the short-wavelength velocity structures. We developed our method in two synthetic tests and then applied it to a marine field data set. We evaluated the results of the use of refracted and reflected waves, which was critical for accurately building the long-wavelength velocity model. We showed that our wave-equation tomography strategy was robust for the real data application.

3‐D tomographic static correction

Geophysics ◽  
2002 ◽  
Vol 67 (4) ◽  
pp. 1275-1285 ◽  
Author(s):  
Xu Chang ◽  
Yike Liu ◽  
Hui Wang ◽  
Fuzhong Li ◽  
Jing Chen
Keyword(s):  
Computation Time ◽  
Matrix Decomposition ◽  
Velocity Model ◽  
Seismic Survey ◽  
Surface Model ◽  
Low Velocity ◽  
Near Surface ◽  
Model Inversion ◽  
Static Corrections ◽  
Refracted Waves

A 3‐D tomographic inversion approach based on a surface‐consistent model for static corrections is presented in this paper. Direct, reflected, and refracted waves are used simultaneously to update the near‐surface model. We analyze the characteristics of the first‐break traveltime in complicated low‐velocity layers. To improve the accuracy for the velocity model, the various first‐break times from direct, reflected, and refracted waves are considered for model inversion. A fractal algorithm which overcomes the error caused by wavelet shape differences is applied to pick first breaks. It also overcomes the leg jump of refractions. The method can pick a large number of first breaks automatically. The raypaths and traveltimes are calculated with a 3‐D ray tracer that does not increase computation time for complicated geological models. Our method can determine the raypath associated with minimum traveltimes regardless of wave mode (direct, refracted, or reflected). We use a least‐squares approach in conjunction with a matrix decomposition to reconstruct a 3‐D velocity model from the actual first‐break times obtained from 3‐D data. Finally, long‐ and short‐wavelength static corrections are calculated concurrently, based on the reconstructed velocity profile. The method can be applied to wide‐line profiles, crooked lines, and 2‐D and 3‐D seismic survey geometries. The results applied to a real 3‐D data example indicate that the 3‐D tomographic static corrections are effective for field data.

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