Transmission filtering by high‐amplitude reflection coefficients: Theory, practice, and processing considerations

1996 ◽  
Vol 15 (9) ◽  
pp. 1037-1042 ◽  
Author(s):  
Craig A. Coulombe ◽  
D. Neil Bird
Keyword(s):  
High Amplitude ◽  
Reflection Coefficients ◽  
Amplitude Reflection

Results of a seismic reflection survey across the fault zone between the Thompson nickel belt and the Churchill Tectonic Province, northern Manitoba

1981 ◽  
Vol 18 (1) ◽  
pp. 13-25 ◽  
Author(s):  
A. G. Green
Keyword(s):  
Fault Zone ◽  
Lower Crust ◽  
Seismic Reflection ◽  
High Amplitude ◽  
Small Scale ◽  
Upper Crust ◽  
Travel Times ◽  
Reflection Point ◽  
Point Data ◽  
Amplitude Reflection

Approximately 11 km of four-fold common reflection point data have been recorded across a region that spans the contact fault zone between the Thompson nickel belt and the Churchill Tectonic Province. From these data it is shown that the upper crust in this region and, to a lesser extent, the lower crust are characterized by numerous scattered events that originate from relatively small-scale features. Within the Thompson nickel belt two extensive and particularly high-amplitude reflection zones, at two-way travel times of t = 5.0–5.5 s and t = 6.0–6.5 s, are recorded with apparent northwesterly dips of 0–20 °C. These reflection zones, which have a laminated character, are truncated close to the faulted contact with the Churchill Province. Both the contact fault zone and the Churchill Province in this region have crustal sections that are relatively devoid of significant reflectors. The evidence presented here confirms that the crustal section of the Thompson nickel belt is fundamentally different from that of the Churchill Tectonic Province.

scholarly journals Seismic Characteristics of Mud Diapir in Song Hong Basin, Offshore Vietnam

2021 ◽  
Vol 54 (2A) ◽  
pp. 1-10
Author(s):  
Anh Ngoc Le
Keyword(s):  
Oil And Gas ◽  
High Amplitude ◽  
High Energy ◽  
Hydrocarbon Generation ◽  
Red River Basin ◽  
Seismic Characteristics ◽  
Mud Diapir ◽  
The Relationship ◽  
Seismic Lines ◽  
Amplitude Reflection

Seismic characteristics of mud diapir has been investigate over an area of 3900 km2, located in the central part of Song Hong basin, using four 2D seismic lines. There are six mud diapirs and three mud pipes have been documented. The core of the diapir is characterized as a zone of chaotic, disrupted seismic reflection, with the amplitude reflection ranging from low the high. High amplitude reflections are distributed in the top of the some diapir, which is possibly related to the gas accumulation. They are in different sizes, shapes, and the relationship with surrounding rock. They are characterized as deep sourced, high energy rooting from Oligocene/early Miocene shale layers. This organic rich shale rocks are in the oil and gas windows, thus their hydrocarbon generation combining with the tectonic inversion during Miocene make the overpressured shale and therefore rising the diaipirs. The area has experienced several phases of eruption in Middle Miocene, Late Miocene, Late Pliocene and Present day. The discovery and identification of the occurrence of mud diapirs implied a great potential for prediction of structural traps in the central part of the Red River Basin.

scholarly journals Electromagnetic Reflection from Multi-Layered Snow Models

1975 ◽  
Vol 14 (72) ◽  
pp. 501-515 ◽  
Author(s):  
William I. Linlor ◽  
George R. Jiracek
Keyword(s):  
Water Resource Management ◽  
Plane Waves ◽  
Electromagnetic Response ◽  
Effective Dielectric Constant ◽  
Reflection Coefficients ◽  
Snow Layer ◽  
Flood Prediction ◽  
Incident Plane ◽  
Simplifying Assumptions ◽  
Amplitude Reflection

The remote sensing of snow-pack characteristics with surface installations or an airborne system could have important applications in water-resource management and flood prediction. To derive some insight into such applications, the electromagnetic response of multi-layered snow models is analyzed in this paper. Normally incident plane waves at frequencies ranging from 106 to 1010 Hz are assumed, and amplitude reflection coefficients are calculated for models having various snow-layer combinations, including ice layers. Layers are defined by a thickness, permittivity, and conductivity; the electrical parameters are constant or prescribed functions of frequency. To illustrate the effect of various layering combinations, results are given in the form of curves of amplitude reflection coefficients versus frequency for a variety of models. Under simplifying assumptions, the snow thickness and effective dielectric constant can be estimated from the variations of reflection coefficient as a function of frequency.

scholarly journals Electromagnetic Reflection from Multi-Layered Snow Models

1975 ◽  
Vol 14 (72) ◽  
pp. 501-515
Author(s):  
William I. Linlor ◽  
George R. Jiracek
Keyword(s):  
Water Resource Management ◽  
Plane Waves ◽  
Electromagnetic Response ◽  
Effective Dielectric Constant ◽  
Reflection Coefficients ◽  
Snow Layer ◽  
Flood Prediction ◽  
Incident Plane ◽  
Simplifying Assumptions ◽  
Amplitude Reflection

The remote sensing of snow-pack characteristics with surface installations or an airborne system could have important applications in water-resource management and flood prediction. To derive some insight into such applications, the electromagnetic response of multi-layered snow models is analyzed in this paper. Normally incident plane waves at frequencies ranging from 106 to 1010 Hz are assumed, and amplitude reflection coefficients are calculated for models having various snow-layer combinations, including ice layers. Layers are defined by a thickness, permittivity, and conductivity; the electrical parameters are constant or prescribed functions of frequency. To illustrate the effect of various layering combinations, results are given in the form of curves of amplitude reflection coefficients versus frequency for a variety of models. Under simplifying assumptions, the snow thickness and effective dielectric constant can be estimated from the variations of reflection coefficient as a function of frequency.

scholarly journals Stratigraphic Trap in the Permian Unayzah Formation, Central Saudi Arabia

GeoArabia ◽  
1997 ◽  
Vol 2 (3) ◽  
pp. 259-278 ◽  
Author(s):  
Daniel S. Evans ◽  
Bassam H. Bahabri ◽  
Ahmed M. Al-Otaibi
Keyword(s):  
Saudi Arabia ◽  
Source Rock ◽  
High Amplitude ◽  
Seismic Survey ◽  
Lower Silurian ◽  
Eastern Flank ◽  
The North ◽  
Light Oil ◽  
Trap Potential ◽  
Amplitude Reflection

ABSTRACT The recent discovery in Central Saudi Arabia of Arabian Super Light oil in 'Usaylah-1 confirms stratigraphic trap potential of the Permian Unayzah Formation. The trap is an updip pinch-out of an upper Unayzah sandstone along the eastern flank of the north-south trending Hawtah anticline. The seal is the basal shales and siltstones of the Khuff and Unayzah formations and the source rock is the Lower Silurian Qusaiba Shale. The well encountered an oil column of 31 feet in an upper Unayzah eolian dune facies. The areal distribution of the prospect was mapped with a 3-D seismic survey. Seismic horizon slices and relative amplitude maps at the target reflection clearly delineate the trap. The oil-productive Unayzah sandstone is imaged as a high-amplitude reflection in an isolated area of approximately 8 square kilometers. Seismic isochron maps are proving effective in focusing future exploration to areas of similar stratigraphic trap potential in the region.

TO TACKLE THE DECONVOLUTION PROBLEM — A POWERFUL METHOD BASED ON MORE GEOLOGICAL HYPOTHESES

1986 ◽  
Vol 26 (1) ◽  
pp. 192
Author(s):  
E. Denelle
Keyword(s):  
High Amplitude ◽  
Hydrocarbon Exploration ◽  
Reflection Coefficients ◽  
Seismic Section ◽  
Seismic Processing ◽  
Seismic Prospecting ◽  
Generalized Inversion ◽  
Reflectivity Spectra ◽  
Deconvolution Problem ◽  
Reflectivity Function

The new rules of the game in hydrocarbon exploration demand an exact positioning of the seismic markers in order to define the geometry of the targets more than ever before. However, the degree of success will depend to a great extent on how accurately the amplitude of reflection coefficients can be estimated.These new requirements mean that all stages of traditional seismic processing have to be critically evaluated. It can be seen, in particular, when assessing existing deconvolution methods for seismic processing, that they are often ill-conditioned to problems posed by the targets of stratigraphic exploration or by reservoir seismic prospecting. The amplitude of the reflectivity function is often estimated inaccurately.The approach described in this paper abandons the usual hypothesis (white reflectivity spectra) made by deconvolution methods and employs as alternative information the lateral redundancies which are always present on a seismic section. Our method first estimates the location of high amplitude reflectors with good lateral continuity, by means of an elegant automatic picking program. Based on these locations, a generalized inversion can be used to yield the wavelet emitted by the source, and the amplitude of the main reflection coefficients simultaneously for each trace. All the reflection coefficients are then estimated using the amplitudes and the wavelets computed previously.The various stages of this method which is called Deconvolution-Inversion, developed by Total Compagnie Française des Pétroles, are illustrated in the paper by means of both synthetic and real examples. The ability of the method to preserve the amplitudes makes it a powerful tool for stratigraphic and reservoir seismic prospecting purposes.

Reflection Coefficients at Collagen Interfaces in Soft Tissues

1979 ◽  
Vol 1 (4) ◽  
pp. 346-355 ◽  
Author(s):  
Avtar S. Ahuja
Keyword(s):  
Normal Tissue ◽  
Elastic Moduli ◽  
Soft Tissues ◽  
Reflection Coefficients ◽  
Body Model ◽  
The Matrix ◽  
Correlation Parameters ◽  
Tissue Matrix ◽  
Amplitude Reflection

For the purpose of ultrasonic imaging, soft tissue has been modeled as a viscoelastic (Voigt) composite material consisting of collagen fibers (as the inhomogeneity) embedded in a continuum tissue (as the matrix). It is known that infarction enhances the collagen content in myocardial tissues. The published in vitro attenuation data in normal and infarcted myocardial tissues have been correlated with the Voigt body model. From the correlation parameters and mixture laws for the elastic moduli of tissue components, the bulk modulus of collagen has been estimated to be about 50–55% higher than that of the normal tissue. From a knowledge of the bulk moduli and mass densities of collagen and tissue matrix, amplitude reflection coefficients at collagen interfaces have been computed. The amplitude reflection coefficient at the saline-collagen or at the collagen-myocardium interface is about 6 times that at the saline-myocardium interface.

Sign in / Sign up

Export Citation Format

Share Document