scholarly journals A New Method to Extract CSP Gather of Topography for Scattered Wave Imaging

2017 ◽  
Vol 2017 ◽  
pp. 1-7
Author(s):  
Zhao Pan ◽  
Zhang Mei-gen
Keyword(s):  
Conventional Method ◽  
Seismic Data ◽  
Scattered Wave ◽  
Earth Surface ◽  
Numerical Examples ◽  
The Earth ◽  
Imaging Result ◽  
Wave Imaging ◽  
The Common ◽  
Rugged Surface

The seismic method is one of the major geophysical tools to study the structure of the earth. The extraction of the common scatter point (CSP) gather is a critical step to accomplish the seismic imaging with a scattered wave. Conventionally, the CSP gather is obtained with the assumption that the earth surface is horizontal. However, errors are introduced to the final imaging result if the seismic traces obtained at the rugged surface are processed using the conventional method. Hence, we propose the method of the extraction of the CSP gather for the seismic data collected at the rugged surface. The proposed method is validated by two numerical examples and expected to reduce the effect of the topography on the scattered wave imaging.

Near-surface scattered waves enhancement with source-receiver interferometry

Geophysics ◽  
2018 ◽  
Vol 83 (6) ◽  
pp. Q49-Q69
Author(s):  
Jixiang Xu ◽  
Shitai Dong ◽  
Huajuan Cui ◽  
Yan Zhang ◽  
Ying Hu ◽  
...  
Keyword(s):  
Seismic Data ◽  
Seismic Waves ◽  
Scattered Wave ◽  
Receiver Functions ◽  
Surface Velocity ◽  
Seismic Exploration ◽  
Common Source ◽  
Constructive Interference ◽  
Near Surface ◽  
The Common

Near-surface scattered waves (NSWs) are the main noise in seismic data in areas with a complex near surface and can be divided into surface-to-surface scattered waves and body-to-surface scattered waves. We have developed a method for NSW enhancement that uses modified source-receiver interferometry. The method consists of two parts. First, deconvolutional intersource interferometry is used to cancel the common raypath of seismic waves from a near-surface scatterer to the common receiver and the receiver function. Second, convolutional interreceiver interferometry is used to compensate the common raypath of seismic waves from the common source to the near-surface scatterer and the source function. For an isotropic point scatterer near the earth’s surface in modified source-receiver interferometry, a body-to-surface scattered wave can be reconstructed by constructive interference not only among three body-to-surface scattered waves but also among a body-to-surface scattered wave and two surface-to-surface scattered waves; a surface-to-surface scattered wave can be reconstructed by constructive interference not only among three surface-to-surface scattered waves but also among a surface-to-surface scattered wave and two body-to-surface scattered waves. According to stationary phase analysis based on the superposition principle, we have developed a so-called dual-wheel driving configuration of modified source-receiver interferometry for enhancing NSWs in the data of conventional seismic exploration. The main advantages of the scheme are that (1) it can be used to enhance NSWs without the need for any a priori knowledge of topography and near-surface velocity, (2) it can be used to reconstruct NSWs from real sources to real receivers, including 3D near-surface side-scattered waves, and (3) it can be applied to conventional seismic data with finite-frequency bandwidth, spatially limited and sparse arrays, different source and receiver functions, and static correction. Numerically simulated data and field seismic data are used to demonstrate the feasibility and effectiveness of the scheme.

The influence of out‐of‐plane surface properties on unmigrated time sections

Geophysics ◽  
1983 ◽  
Vol 48 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Jack K. Cohen ◽  
Norman Bleistein
Keyword(s):  
Seismic Data ◽  
High Frequency ◽  
Plane Surface ◽  
Specular Reflection ◽  
Scattered Wave ◽  
Principal Curves ◽  
Reflection Point ◽  
Numerical Examples ◽  
Out Of Plane ◽  
Seismic Sections

Both analytic and numerical means are used to demonstrate amplitude and phase behavior of reflections from three‐dimensionally curved interfaces. In particular, the high‐frequency geometrical optics approximation for the backward scattered wave field demonstrates that the phase of a reflection from a syncline is determined by the (in general, different) positions of focal regions for the two principal curves at the specular reflection point. Thus the amplitudes and phases of events observed on seismic sections are influenced as much by the shape of the reflector “out‐of‐the‐plane” as by the shape in the plane of the section. Results of the numerical examples suggest possible pitfalls in traditional interpretation of two‐dimensional seismic data.

Basis for the technique of the external control of the optical equipment for the remote sensing of the Earth surface

1997 ◽  
Vol 3 (3-4) ◽  
pp. 50-53
Author(s):  
O.D. Fedorovskyi ◽  
◽  
V.I. Kononov ◽  
K.Yu. Sukhanov ◽  
◽  
...  
Keyword(s):  
Remote Sensing ◽  
External Control ◽  
Earth Surface ◽  
The Earth

ESTIMATION OF THE EARTH SURFACE TEMPERATURE BY HIMAWARI-8/AHI

2016 ◽  
Vol 72 (2) ◽  
pp. II_1-II_6 ◽  
Author(s):  
Yuuki UCHIDA ◽  
Tomohito ASAKA ◽  
Takashi NONAKA ◽  
Keishi IWASHITA ◽  
Toshiro SUGIMURA
Keyword(s):  
Surface Temperature ◽  
Earth Surface ◽  
The Earth

Effects of incomplete parameterization on full-wavefield viscoelastic seismic data for petrophysical reservoir properties

Geophysics ◽  
2007 ◽  
Vol 72 (3) ◽  
pp. O9-O17 ◽  
Author(s):  
Upendra K. Tiwari ◽  
George A. McMechan
Keyword(s):  
Seismic Data ◽  
Input Data ◽  
Elastic Model ◽  
Quality Factors ◽  
Noise Levels ◽  
Reservoir Properties ◽  
Estimated Parameters ◽  
Model Parameterization ◽  
The Earth ◽  
Incomplete Model

In inversion of viscoelastic full-wavefield seismic data, the choice of model parameterization influences the uncertainties and biases in estimating seismic and petrophysical parameters. Using an incomplete model parameterization results in solutions in which the effects of missing parameters are attributed erroneously to the parameters that are included. Incompleteness in this context means assuming the earth is elastic rather than viscoelastic. The inclusion of compressional and shear-wave quality factors [Formula: see text] and [Formula: see text] in inversion gives better estimates of reservoir properties than the less complete (elastic) model parameterization. [Formula: see text] and [Formula: see text] are sensitive primarily to fluid types and saturations. The parameter correlations are sensitive also to the model parameterization. As noise increases in the viscoelastic input data, the resolution of the estimated parameters decreases, but the parameter correlations are relatively unaffected by modest noise levels.

WHITE ANTS DESTROYING LIVING TREES AND CHANGING THF FOLIAGE, IN CAMBRIDGE, MASS

1885 ◽  
Vol 17 (7) ◽  
pp. 134-136
Author(s):  
H. A. Hagen
Keyword(s):  
Dead Wood ◽  
The South ◽  
The Earth ◽  
The Common

The common white ant, Termes flavipes, destroys dead wood, stumps of trees and timber, just as does its nearest relative, T. lucifugus, in Europe. Of the latter species some cases are reported where living pines and oaks have been destroyed in the South of France. For T. flavipes, only one case is known, in which living grape vines in a hot house in Salem were injured. (S. H. Scudder. Proc. Boston, N. H. S., vol. 7, p. 287). Now the earth in the hot houses here in Cambridge is largely infested by white ants, but as far as I know, no destruction of plants has been observed. I was very much interested by the information from Mr. F. W. Putnam that in a garden in Irwing street living maples were largely infested by white ants. The evidence of the truth of this information was apparent by the first glance at the trees.

Edges of Regression and Limit Normal Point of Conjugate Surfaces1

1998 ◽  
Vol 122 (4) ◽  
pp. 419-425 ◽  
Author(s):  
Ningxin Chen
Keyword(s):  
Differential Geometry ◽  
Contact Boundary ◽  
Boundary Line ◽  
Tangent Point ◽  
Common Tangent ◽  
Numerical Examples ◽  
Envelope Surface ◽  
The Common ◽  
Conjugate Surfaces ◽  
Definition Of

The presented paper utilizes the basic theory of the envelope surface in differential geometry to investigate the undercutting line, the contact boundary line and the limit normal point of conjugate surfaces in gearing. It is proved that (1) the edges of regression of the envelope surfaces are the undercutting line and the contact boundary line in theory of gearing respectively, and (2) the limit normal point is the common tangent point of the two edges of regression of the conjugate surfaces. New equations for the undercutting line, the contact boundary line and the limit normal point of the conjugate surfaces are developed based on the definition of the edges of regression. Numerical examples are taken for illustration of the above-mentioned concepts and equations. [S1050-0472(00)00104-5]

scholarly journals XXIII. On the degree of salubrity of the common air at sea, compared with that of the sea-shore, and that of places far removed from the sea

1780 ◽  
Vol 70 ◽  
pp. 354-377 ◽  
Keyword(s):  
The Earth ◽  
The Face ◽  
The Common ◽  
In The Beginning ◽  
Bodies Of Water

Sir, As you had recommended to me the examination of the air at sea by the nitrous test, I followed your advice in my return to the Continent in the beginning of November last: and I embraced that opportunity with the more eagerness, as I knew that you had given credit to the account of several consumptive people having recovered their health by going on sea voyages, after the common means for curing that distemper had failed. I was in hopes likewise to find in this inquiry, a confirmation of what you conjectured in you Anniversary Discourse in the year 1773, viz . that great bodies of water, such as seas and lakes, are conducive to the health of animals, by purifying and cleansing the air contaminated by their breathing in it: so that the salutary gales, by which this infected air is conveyed to the waters, and by them returned again to the land, though they do rise now and then to storms and hurricanes, must nevertheless induce us to trace and to reverse in them the ways of a beneficent Being, who, not fortuitously, but with design, not in wrath, but in mercy, thus shakes the waters and the air together, to bury in the deep those pestilential effluvia which the vegetables upon the face of the earth are insufficient to consume.

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