scholarly journals A survey on multiscale mollifier decorrelation of seismic data

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
C. Blick ◽  
S. Eberle
Keyword(s):  
Seismic Data ◽  
Structural Features ◽  
Processing Method ◽  
Multiscale Approach ◽  
Post Processing ◽  
Salt Domes ◽  
Survey Paper ◽  
Geological Models ◽  
Navier Equation ◽  
Geological Formations

AbstractIn this survey paper, we present a multiscale post-processing method in exploration. Based on a physically relevant mollifier technique involving the elasto-oscillatory Cauchy–Navier equation, we mathematically describe the extractable information within 3D geological models obtained by migration as is commonly used for geophysical exploration purposes. More explicitly, the developed multiscale approach extracts and visualizes structural features inherently available in signature bands of certain geological formations such as aquifers, salt domes etc. by specifying suitable wavelet bands.

Multiattribute Seismic Analysis With Fractal Dimension and 2D and 3D Continuous Wavelet Transform

2014 ◽  
Vol 17 (04) ◽  
pp. 436-443 ◽  
Author(s):  
Puneet Saraswat ◽  
Vijay Raj ◽  
Mrinal K. Sen ◽  
Arun Narayanan
Keyword(s):  
Fractal Dimension ◽  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Seismic Data ◽  
Seismic Analysis ◽  
Seismic Attributes ◽  
Structural Features ◽  
Primary Concern ◽  
Continuous Wavelet ◽  
Salt Domes

Summary The 3D post-stack seismic attributes provide an intuitive and effective way of using seismic volumes for reservoir characterization and development, and further identification of exploration targets. Some of the seismic attributes can aid in the precise prediction of the geometry and heterogeneity of subsurface geological settings. These also can provide useful information on petrophysical and lithological properties when combined with well-log information. There exist numerous seismic attributes that provide a unique interpretation on some aspects of subsurface geology. Of these, the proper demarcation of structural features— such as location and edges of faults and salt domes, and their throw and extent—always has been of primary concern. In this paper, we propose new multiattribute seismic algorithms by using fractal dimension and 2D/3D continuous wavelet transform (CWT). The use of higher-dimensional wavelets incorporates information from the ensemble of traces and can correlate information between neighboring traces in seismic data. The spectral decomposition that is based on the CWT aids in resolving various features of geological interest at a particular scale or frequency, which, when rendered with fractal attribute, demarcates the boundaries between those. We apply these two algorithms separately to a seismic amplitude volume and co-render output volumes together with some weights to yield a final attribute volume incorporating information from the aforementioned algorithms. We demonstrate the efficacy of these two algorithms in terms of the resolution and proper demarcation of various geological structures on real seismic data. The application of these algorithms results in better illumination and proper demarcation of various geological features such as salt domes, channels, and faults, and it illustrates how these simple tools can help to extract detailed information from seismic data.

Post Processing Method for Multiple Spinecho Brain MR by grouping voxels by signal decay

1990 ◽  
Vol 25 (12) ◽  
pp. 1355
Author(s):  
S. S. Winkler ◽  
Y. H. Kao ◽  
J. A. Sorenson
Keyword(s):  
Processing Method ◽  
Post Processing ◽  
Signal Decay

scholarly journals Similar understorey structure in spite of edaphic and floristic dissimilarity in Amazonian forests

2015 ◽  
Vol 45 (4) ◽  
pp. 393-404 ◽  
Author(s):  
Lassi SUOMINEN ◽  
Kalle RUOKOLAINEN ◽  
Timo PITKÄNEN ◽  
Hanna TUOMISTO
Keyword(s):  
Satellite Imagery ◽  
Forest Structure ◽  
Satellite Image ◽  
Light Availability ◽  
Floristic Composition ◽  
Structural Features ◽  
Canopy Openness ◽  
Understorey Plants ◽  
Amazonian Forests ◽  
Geological Formations

Forest structure determines light availability for understorey plants. The structure of lowland Amazonian forests is known to vary over long edaphic gradients, but whether more subtle edaphic variation also affects forest structure has not beenresolved. In western Amazonia, the majority of non-flooded forests grow on soils derived either from relatively fertile sediments of the Pebas Formation or from poorer sediments of the Nauta Formation. The objective of this study was to compare structure and light availability in the understorey of forests growing on these two geological formations. We measured canopy openness and tree stem densities in three size classes in northeastern Peru in a total of 275 study points in old-growth terra firme forests representing the two geological formations. We also documented variation in floristic composition (ferns, lycophytes and the palm Iriartea deltoidea) and used Landsat TM satellite image information to model the forest structural and floristic features over a larger area. The floristic compositions of forests on the two formations were clearly different, and this could also be modelled with the satellite imagery. In contrast, the field observations of forest structure gave only a weak indication that forests on the Nauta Formation might be denser than those on the Pebas Formation. The modelling of forest structural features with satellite imagery did not support this result. Our results indicate that the structure of forest understorey varies much less than floristic composition does over the studied edaphic difference.

scholarly journals Optimization of Magnetic Properties of Magnetic Microwires by Post-Processing

Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 1006
Author(s):  
Valentina Zhukova ◽  
Paula Corte-Leon ◽  
Lorena González-Legarreta ◽  
Ahmed Talaat ◽  
Juan Maria Blanco ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Chemical Composition ◽  
Hysteresis Loops ◽  
Structural Features ◽  
Post Processing ◽  
Soft Magnetic ◽  
Magnetic Microwires ◽  
Prepared State ◽  
Induced Magnetic Anisotropy ◽  
Selection Of

The influence of post-processing conditions on the magnetic properties of amorphous and nanocrystalline microwires has been thoroughly analyzed, paying attention to the influence of magnetoelastic, induced and magnetocrystalline anisotropies on the hysteresis loops of Fe-, Ni-, and Co-rich microwires. We showed that magnetic properties of glass-coated microwires can be tuned by the selection of appropriate chemical composition and geometry in as-prepared state or further considerably modified by appropriate post-processing, which consists of either annealing or glass-coated removal. Furthermore, stress-annealing or Joule heating can further effectively modify the magnetic properties of amorphous magnetic microwires owing to induced magnetic anisotropy. Devitrification of microwires can be useful for either magnetic softening or magnetic hardening of the microwires. Depending on the chemical composition of the metallic nucleus and on structural features (grain size, precipitating phases), nanocrystalline microwires can exhibit either soft magnetic properties or semi-hard magnetic properties. We demonstrated that the microwires with coercivities from 1 A/m to 40 kA/m can be prepared.

Sign in / Sign up

Export Citation Format

Share Document