A REFRACTION THEORY ADAPTABLE TO SEISMIC WEATHERING PROBLEMS

Geophysics ◽  
1941 ◽  
Vol 6 (3) ◽  
pp. 245-253 ◽  
Author(s):  
H. E. Banta
Keyword(s):  
Vertical Velocity ◽  
Seismic Waves ◽  
Time Distance ◽  
Velocity Of Propagation ◽  
Time Relation ◽  
Distance Relation ◽  
Exponential Relation

An exponential relation [Formula: see text] between depth and velocity of propagation of seismic waves is postulated. The exponent is a number between zero and unity. Expressions for the time‐distance relation, the depth‐distance relation, the average vertical velocity, and the vertical time‐horizontal time relation are derived. Applications of the relations to seismic weathering problems are discussed.

VERTICAL VELOCITIES FROM REFLECTION SHOOTING

Geophysics ◽  
1947 ◽  
Vol 12 (2) ◽  
pp. 221-228 ◽  
Author(s):  
L. W. Gardner
Keyword(s):  
Vertical Velocity ◽  
Seismic Waves ◽  
Ground Surface ◽  
Comparison Of Results ◽  
Favorable Conditions

Reflection seismograph observations supply a means of determining the average vertical velocity of seismic waves from the ground surface to the depth of any good reflecting horizon, through measurements of “angularity corrections.” Specially grouped arrangements of shot points and detectors are illustrated and described, which minimize error in making these measurements. Reflection seismograph observations using these arrangements were made at four locations where well velocity surveys were available. Comparison of results indicates that average vertical velocities good to within 3% can be obtained by this method, under favorable conditions.

A NOTE ON THE PROPAGATION OF SEISMIC WAVES

Geophysics ◽  
1937 ◽  
Vol 2 (4) ◽  
pp. 319-328 ◽  
Author(s):  
Morris Muskat
Keyword(s):  
Wave Propagation ◽  
Power Series ◽  
Conventional Method ◽  
Seismic Wave ◽  
Seismic Waves ◽  
Seismic Wave Propagation ◽  
Time Distance

It is suggested that in the computation of theoretical time‐distance curves for seismic wave propagation a more tractable form of analysis is obtained if the depth is expressed as a power series in the velocity than when the converse but more conventional method is used. Several illustrations of this procedure are given.

scholarly journals Computer model of seismic waves vertical velocity distribution for central part of the Dniprovsko-Donetsk depression

2013 ◽  
pp. 62-70
Author(s):  
P. Zagorodnyuk ◽  
G. Lisny ◽  
V. Ryumin ◽  
E. Ustenko
Keyword(s):  
Computer Model ◽  
Vertical Velocity ◽  
Seismic Waves ◽  
Oil And Gas ◽  
New Technologies ◽  
Seismic Survey ◽  
Seismic Exploration ◽  
Donets Basin ◽  
Velocity Anisotropy ◽  
Velocity Modeling

The article states the principles of layered media velocity modeling and the results of computer modeling of the value distribution of the vertical velocity of seismic waves in the central part of the Dnieper-Donets Basin. The computer model is used to integrate the seismic survey data, and to enhance the efficiency of seismic exploration for oil and gas. It is achieved through the application of new technologies for data processing with respect to velocity anisotropy, as well as through the use of traditional approaches.   

Analysis for vertical velocity of seismic waves

1989 ◽  
Vol 12 (2) ◽  
pp. 165-177
Author(s):  
Cheng‐Hsing Chen ◽  
Li‐Yen Chen
Keyword(s):  
Vertical Velocity ◽  
Seismic Waves

XIV.—The Propagation of Earthquake Waves through the Earth, and connected Problems

1920 ◽  
Vol 39 ◽  
pp. 157-208 ◽  
Author(s):  
C. G. Knott
Keyword(s):  
Royal Society ◽  
Seismic Waves ◽  
Functional Relation ◽  
Present Communication ◽  
Method Of Calculation ◽  
The Earth ◽  
Velocity Of Propagation

This paper is a continuation of two papers on Seismic Radiations published in the Proceedings of the Royal Society of Edinburgh, vol. xxviii, pp. 217–230 (1907–8) and vol. xxx, pp. 23–37 (1909). The object of the present communication is to place on record a new determination of the laws of propagation of seismic waves based upon a method of calculation in which no assumptions are made as to the functional relation between velocity of propagation and distance from the earth's centre. References to the work of others will be given incidentally as occasion arises.

scholarly journals Modeling Asymmetry in the Time–Distance Relation of Ordinal Personality Items

2021 ◽  
pp. 014662162199075
Author(s):  
Dylan Molenaar ◽  
Sandor Rózsa ◽  
Natasa Kõ
Keyword(s):  
Simulation Study ◽  
Response Times ◽  
Latent Trait ◽  
Personality Test ◽  
Personality Questionnaire ◽  
Temperament And Character Inventory ◽  
Test Items ◽  
Character Inventory ◽  
Time Distance ◽  
Distance Relation

In analyzing responses and response times to personality questionnaire items, models have been proposed which include the so-called “inverted-U effect.” These models predict that response times to personality test items decrease as the latent trait value of a given person gets closer to the attractiveness of an item. Initial studies into these models have focused on dichotomous personality items, and more recently, models for Likert-type scale items have been proposed. In all these models, it is assumed that the inverted-U effect is symmetrical around 0, while, as will be explained in this article, there are substantive and statistical reasons to study this assumption. Therefore, in this article, a general inverted-U model is proposed which accommodates two sources of asymmetry between the response times and the attractiveness of the items. The viability of this model is demonstrated in a simulation study, and the model is applied to the responses and response times of the Temperament and Character Inventory–Revised, covering a broad range of personality dimensions.

scholarly journals A study of the seismic waves SKS and SKKS*

1954 ◽  
Vol 44 (1) ◽  
pp. 39-55
Author(s):  
Robert L. Nelson
Keyword(s):  
Seismic Waves ◽  
Slight Modification ◽  
Travel Times ◽  
Time Data ◽  
Arrival Times ◽  
The Core ◽  
Time Distance ◽  
Epicentral Location ◽  
Fault Source ◽  
Good Agreement

abstract Arrival times, amplitudes, and periods of the seismic phases SKS and SKKS have been investigated for shallow, intermediate, and deep earthquakes recorded at Pasadena and Huancayo, Peru. New observed time-distance curves are constructed for depths of <60, 100, 200, and 600 kilometers. Travel times for the core have been calculated from shallow-shock time data. Slight modification of wave velocity just inside the core and of travel times within the core are suggested. Calculated travel times of SKS, SKKS, and SKKKS are in good agreement with observations. Energy parameters determined from observed amplitude/period ratios are found in only fair agreement with those calculated from theory. Observed energies are too large for most of the phase components and depths considered. The horizontal components of SKKS over the whole distance range, and of SKS at Δ ≦ 100° for all depths, yield observed energies less than those predicted by theory. Both discrepancies are at least qualitatively explained by a proposed nonspherical distribution of shear strain about the fault source, and by abnormal absorption in the outer 700 kilometers of the core. Anomalous observed energies, as functions of epicentral location, are also accounted for by the proposed nonspherical distribution of energy.

REFRACTION DETERMINATION OF WATER TABLE DEPTH AND ALLUVIUM THICKNESS

Geophysics ◽  
1968 ◽  
Vol 33 (3) ◽  
pp. 481-488 ◽  
Author(s):  
James Otto Duguid
Keyword(s):  
Ground Water ◽  
Water Table ◽  
Seismic Wave ◽  
Seismic Waves ◽  
Water Table Depth ◽  
Ground Water Table ◽  
Weathered Zone ◽  
Time Distance

During an investigation of alluvium using a shallow refraction seismograph, time‐distance curves obtained indicated two refraction interfaces. The shallower of the interfaces is the ground‐water table, whose depth was obtained with an accuracy of ±10 percent. The deeper interface is either the surface of the bedrock or the base of the weathered zone on the bedrock. If this lower interface is the surface of the bedrock, the velocity of seismic waves in the weathered material will be considerably lower than if the interface is the base of the weathered zone. Using this criteria makes it possible to determine whether the seismic wave is refracted from the surface of the bedrock or the base of the weathered zone.

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