bluuebunny/crossref_metadata_2025 huggingface dataset:
The in vitro and in vivo effect of corticosteroides on basophi releasabihty in patients with mild and severe bronchial asthma
Authors: KIVITY S. , ONN A. , AGAMI O. , FIREMAN E.
Published: April 2006

Background
While inhalation of corticosteroids (CST) is considered very effective in most asthmatic patients, some require a high dose of orul prcdnisonc to control the disease. Basophils, which participate in inflammation, are responsive to cortiseosteroids by suppressing histamine release.

Objectives
We investigated the in vivo (oral prednisone) and in vitro (dexamethasone, DEX) effect on basophil histamine release in mild and steroid‐dependent asthmatics.

Methods
Histamine release from basophils to anti‐IgE and anti‐IgE + IL3 was evaluated following live days of prednisone given 20 mg twice daily in eight subjects with mild disease and 2 h following their daily prednisone ingestion in eight subjects with severe disease, as well as after in vitro DEX was added to the cells.

Results
Histamine release from basophils was seen following anti‐ IgE as well as anti‐IgE + IL‐3. The same amount of release was seen in the mild and severe asthmatics. In vivo prednisone suppressed histamine release to both stimuli and DEX added to the suppression in the mild asthmatics. In the severe ones. DEX showed no inhibitory effect on histamine release.

Conclusion
Oral and in‐vitro CST suppressed histamine release from basophils of mild but not severe CST‐dependent asthmatics. Suppression of basophil releasability can be a reflection of asthma severity.
Increased specificity of diagnostic tests with recombinant major bee venom allergen phospholipase A2
Authors: MÜLLER U. , FRICKER M. , WYMANN D. , BLASER K. , CRAMERI R.
Published: April 2006

Background
In diagnosis of type I allergy recombinant allergens have potential advantages over conventional allergenic extracts, both regarding specificity and reproducibility.

Objectives
We therefore decided to study honey bee venom (BV) and its major allergen phospholipase A2 (PLA) in native and recombinant form for diagnosis of bee sting allergy.

Method
We investigated 85 patients with a history of a recent systemic allergic bee sting reaction and positive intracutaneous skin test to BV, and 21 controls with no history of allergic bee sting reaction and negative skin test to BV. Intracutaneous skin tests and determination of specific IgE by ImmunoCAPR to BV, native PLA (nPLA) and recomhinant PLA (rPLA) were done in all patients and controls.

Results
In skin testing 84 (99%) of the 85 patients reacted to nPLA and 81 (95%) to rPLA, while none of the 21 controls was positive with nPLA or rPLA. Specific serum IgE to BV could be detected in 82 of the patients (96%), to nPLA in 73 (86%) and to rPLA in 66 (78%). Four (19%) of the controls had a positive CAP to BV, one (4.8%) to nPLA and none to rPLA. Analysis of discordant results in CAP showed, that most patients with specific IgE to BV, but not to nPLA and rPLA, had positive skin tests to both PLA preparations and low levels of BV specific IgE. Patients with specific IgE to nPLA but not to rPLA were usually sensitized to minor allergens of BV which contaminated the commercial nPLA.

Conclusions
PLA is the major allergen in BV. While diagnostic tests with BV are more sensitive, the specificity of tests with PLA, especially rPLA is clearly increased as compared with BV.
Crossreactivity and T‐cell epitope specificity of Bet v 1‐specific T cells suggest the involvement of multiple isoallergens in sensitization to birch pollen
Authors: SPARHOLT S. H. , LARSEN J. N. , IPSEN H. , SCHOU C. , VAN NEERVEN R. J. J.
Published: April 2006

Background
Allergen‐specific T lymphocytes play an important role in the pathophysiology of atopic disease. Detailed studies of their epitope‐specificity and crossreactivity are required for the development of novel approaches for specific immunotherapy.

Objectives
The aim of the study was to characterize the fine specificity of Bet v 1‐specific T cells from allergic donors.

Methods
Polyclonal T‐cell lines (TCL) and T‐cell clones (TCC), specific for Bet v 1, the major birch (Betula verrucosa) pollen allergen, were isolated from the peripheral blood of three birch‐allergic patients. Their epitope‐specificity was studied using overlapping synthetic peptides, and crossreactivity with other tree pollen allergens of the Fagales order was evaluated. In addition, the Bet v 1‐specific TCC were studied for their phenotype and cytokine production.

Results
All isolated Bet v 1‐specific TCC (19/21 CD4+, 2/21 CD8+) reacted with affinity purified Bet v 1, but showed different reactivities with recombinant Bet v 1 (rBet v 1), and with group 1 allergens from other Fagales species. Epitope mapping of rBet v 1‐reactive TCC with synthetic peptides of Bet v 1 showed the presence of four T‐cell epitopes. Polyclonal T‐cell lines reacted with 13 different peptides, and displayed even broader crossreactivity with group 1 pollen allergens from other Fagales members.

Conclusion
This study demonstrates that apart from T‐cell epitopes of rBet v 1, many other crossreactive or Bet v 1 isoallergen‐specific epitopes exist. This indicates that isoallergenic variation plays an important role in the induction of Bet v 1‐specific and crossreactive T‐cell responsiveness to allergens.
Determinants of house dust mite allergen in homes in Wellington, New Zealand
Authors: WICKENS K. , SIEBERS R. , ELLIS I. , LEWIS S. , SAWYER G. , TOHILL S. , STONE L. , KENT R. , KENNEDY J. , SLATER T. , CROTHALL A. , TRETHOWEN H. , PEARCE N. , FITZHARRIS P. , CRANE J.
Published: April 2006

Objectives
To measure levels of the major Dermatophagoides pteronyssinus allergen (Der p 1) in homes in Wellington, New Zealand, and to examine factors which affect these levels.

Methods
As part of a study of risk factors for asthma among 474 8–10‐year‐old children, standard procedures were used to collect reservoir dust and to measure Der p 1 levels on the living room floor and child's bedroom floor and bedding. Der p 1 levels were analysed both as geometric mean μg/g of fine dust and as μg/m2. Questionnaires collected information about factors which might influence these levels, and an average relative humidity in the bed and on the bedroom floor was also measured.

Results
Similar geometric mean levels of Der p 1 were found at each floor site – 25.5μg/g (95% CI: 22.8–28.5) in the living room and 26.4 μg/g (95% CI: 23.7–29.3) on the child's bedroom floor. The geometric mean level of Der p 1 in the child's bed was 46.6 μg/g (95% CI: 42.3–51.3). After controlling for possible confounders, geometric mean living room and bedroom floor Der p 1 levels were significantly higher in households with older carpet than households with no carpets or newer carpets, and higher in the autumn. Households with three or more children had higher levels of Der p 1 than households with fewer children. Bedding levels were significantly higher in beds with kapok or inner sprung mattresses, or wool underlays and at relative humidities above the mean (51%).

Conclusion
The very high levels of house dust mite allergen (Der p 1) found in Wellington are likely to be due to a variety of life‐style and climatic factors. However, the type and age of floor covering appears to be the single most important factor.
Transforming growth factor‐β1 and interleukin‐10 in breast milk and development of atopic diseases in infants
Authors: Rigotti E. , Piacentini G. L. , Ress M. , Pigozzi R. , Boner A. L. , Peroni D. G.
Published: April 2006

Background
Precise relationship between breastfeeding and infant allergy is poorly understood.

Objective
Aim was to quantify TGF‐β1 and IL‐10 in colostrum and mature milk from allergic and non‐allergic mothers and to verify relationship with allergic disease development.

Methods
Mothers (13 allergics, nine controls) of 22 newborns participated to prospective study on development of children atopy. Colostrum and mature milk were assayed for TGF‐β1 and IL‐10 by ELISA. Children underwent paediatrician evaluation at 6 months of life.

Results
Data are presented as median values and range. A significant difference in concentration of TGF‐β1 between colostrum (330, range 0–3400 pg/mL) and mature milk (215, range 0–2400 pg/mL) was observed in samples from allergic mothers (P=0.015). In mature milk TGF‐β1 was significantly lower in allergic (215, range 0–2400 pg/mL) than in non‐allergic mothers (1059, range 0–6250 pg/mL) (P=0.015). IL‐10 was weakly expressed without significant differences between allergic (4.8, range 0–42 and 9.5, range 0–42 pg/mL in colostrum and in mature milk) and non‐allergic mothers (0, range 0–42 pg/mL in colostrum and 0, range 0–42 pg/mL in mature milk). After 6 months 46% infants from allergic mothers, but none from controls, presented atopic dermatitis.

Conclusion
TGF‐β1 was significantly less secreted in mature milk of allergic mothers, while no difference in IL‐10 was found. Particular cytokine patterns in milk could influence development of atopic diseases. Further immunological studies in this field are necessary.
Radioimmunoassayable methotrexate concentrations in plasma and skin exudate of patients with psoriasis
Authors: BOOMLA K. , AHERNE G.W. , GREAVES M.W. , QUINTON M.
Published: April 2006

Radioimmunoassay is a rapid, convenient, specific and sensitive method of measuring methotrexate (MTX) levels in plasma and skin exudate. Chronic users have a delayed peak level compared to recently treated patients. MTX levels in skin exudate approximate to those in plasma. Only 50% of plasma MTX is free, whereas almost all is free in skin exudate.
SOME REMARKS ON THE INTERPRETATION OF GRAVITATIONAL AND MAGNETIC ANOMALIES*
Authors: JUNG KARL
Published: April 2006

Abstract

Two geometric methods are given: one for estimating the position of mass distributions from the gravity anomalies, the other for determining the position of a thin plate of magnetized material from the magnetic anomalies. Finally a computational form of Nettleton's method for the determination of density is given.
LAUFZEITMESSUNGEN AN BOHRKERNEN UND GESTEINSPROBEN MIT ELEKTRONISCHEN MITTELN*
Authors: BAULE HEINRICH
Published: April 2006

Abstract

Supersonic pulses are transmitted into rock samples and cylindrical drill cores of about 10 cm to about 100 cm in length by a magnetostrictive driver attached to one end. The pulses are received at any chosen distance along the core by a small crystal geophone resting on the specimen. The beginning of the supersonic pulse and the wave form of the received disturbance, together with the marks of an accurate timer by a quartz clock, are made visual and stationary on the screen of a cathode‐ray oscillograph and the travel‐time is measured. Thus the core is picked up at different distances and a travel‐time curve is drawn from which the velocity of the waves is determined.

The method is interpreted and the measuring device described. Graphs give several travel‐time curves of different rock samples, drill cores, metal rods and rods of other solid materials. The elastic moduli E of the samples are communicated, and an example is given for determining Poisson's ratio S from longitudinal and transversal velocities on two cores of sandstone.
A STUDY OF WELL VELOCITY DATA IN NORTH WEST GERMANY*
Authors: MÜHLEN W. VON ZUR , TUCHEL G.
Published: April 2006

Abstract

The article is based on data from 74 seismic well velocity surveys in N.W. Germany.

The effect of overburden is illustrated by means of diagrams representing interval velocities against depth. To eliminate observational errors and lithological variations from well to well, interval velocities from about the same depth are averaged. Thus, relatively uniform curves are obtained for lower Tertiary, Upper Cretaceous, and Lower Cretaceous (Albian), making the effect of overburden better evident than from individual observations. The vertical gradient of velocity for these geological sections are given. Furthermore, they are compared with curves for Lower Tertiary and Cretaceous obtained in N. America. Due to its high lime content, the Upper Cretaceous of N.W. Germany has a much higher velocity than that observed in the Cretaceous of N. America. The curves for shales of the Lower Tertiary and Lower Cretaceous (Albian), however, are similar in both countries. In older formations, on the other hand, e.g. Jurassic and Triassic, lithologic character has the dominant influence and the effect of overburden is rather small and often scarcely noticeable.

The data considered cover a depth range down to 2,700 meters. The interval velocities are generally based on the use of various equal intervals.
A DEVICE FOR OVERCOMING THE EFFECTS OF STATIC ON SEISMIC SHOT SIGNALS*
Authors: ROBERTS F. A. , DENNISON A. T.
Published: April 2006

Abstract

When refraction time signals are transmitted over a radio link between shooter and observer there is a serious risk of interference from electrical storms. This risk can be minimised by sending a series of signals at fixed time intervals and the paper describes a simple device which will do this with the required accuracy.
BEITRAG ZUR INTERPRETATION VON SCHWEREBILDERN MIT HILFE HöHERER ABLEITUNGEN*
Authors: KOSBAHN B.
Published: April 2006

Abstract

For the treatment of the problems involved in the interpretation of gravity pictures this paper gives a formula that holds generally for any potential function. It provides an extended applicability of the relation used by Elkins for the computation of the second derivative, and also yields an analogous relation to derivatives of higher order of the gravity field.

This relation has not been utilized to determine in details the course of the derivatives of higher order in a plane, but is merely applied to points of comparatively extreme curvature of the isogams where the differential values present a ratio favourable to the “noise level”. By this method the values of the derivatives of higher order will not be determined themselves but only the ratio's responsible for the depth of divergence in comparison with the course of an anomaly of masses replaced by points.

It is shown by examples of intercalated masses that the divergence points are important and by law related to the form and position of the density contrasts themselves.

An analysis of the total gravity picture is made possible by progressing from elements close to the surface to deeper ones. In this way the fundamental features of the earth's crust will be obtained. The application of the analysis process to a gravity anomaly actually measured in Northwest Germany is given.
LAUFZEITANOMALIEN IM BEREICH EINER STöRUNG*
Authors: RÜHMKORF HANS ALBERT
Published: April 2006

Abstract

The measurement of well velocity data in the well of Scheibenhardt I has shown that it is possible to observe a well noticeable measurable increase of the travel time of seismic waves when approaching a disturbance. The tectonic event of the disturbance is combined in this case with a disorder (shattering) of the layers without subsequent cementation.

The significance of these anomalies for reflection seismics is discussed. When existing they will then overlap the diffraction, treated by Th. Krey.
CERTITUDE DES RÉSULTATS DE LA PROSPECTION GÉOPHYSIQUE*
Authors: MATSCHINSKI M.
Published: April 2006

Abstract

The writer classifies problems of geophysical interpretation. He distinguishes four fundamental problems and indicates the methods of solving them. Among these methods he refers to classical methods and methods based on the writer's theoretical work.

The geophysical examples are developed, as well as the very simple numerical examples. Methods of enumeration are also referred to. The whole object is to show that the practical application of the geophysical methods suggested will not give prospectors any difficulty.
QUANTITATIVE STUDIES CONCERNING THE VERTICAL GRADIENT AND SECOND DERIVATIVE METHODS OF GRAVITY INTERPRETATION*
Authors: ROSENBACH OTTO
Published: April 2006

Abstract

In the first part of the present paper we shall investigate the possibility of localising highly situated inclined faults with the aid of the vertical gradient and the second derivative in the direction of the vertical. Since these quantities have been computed from gravity values by means of formulae of approximation we shall have to study the question as to their applicability for possible quantitative interpretation. Particular caution should be exercised when making the usual comparison with theoretical test examples. For three effects have to be taken into account which result from the application of the formulae of approximation:

The extreme values appear more or less smoothed out

Extremal abscissae are being displaced

The results are influenced by the orientation of the grid which forms the basis of the calculation.

For a practical instance it was possible to locate a well under troublesome circumstances. This well is situated on the downthrown side of an inclined fault, the depth of the upthrown side being known as a result of another well.

We shall show in the second part of the present paper how small, deeply situated structures may be recognised in the diagrams of the vertical gradient and of the second derivative. In the case of two practical instances the effect of these structures is rendered unrecognisable in the isogam map in view of regional influences. The results according to the formulae of Baranov, Elkins and Rosenbach are contrasted with each other.
SOME REMARKS ON THE ERRORS IN THE CALCULATION OF THE VERTICAL GRADIENT OF GRAVITY*
Authors: BARANOV V. , TASSENCOURT J.
Published: April 2006

Abstract

In a previous paper by the first author a method has been presented for computing the first vertical derivative of the gravity field or of the magnetic field. In the present paper an analysis is given of the errors in the first vertical derivative that result when the latter is computed by the above method. Two sorts of errors are considered. Firstly, the error in the first vertical derivative that results from the errors in interpolating between isogam lines on the Bouguer anomaly map. Secondly, the error in the first vertical derivative that results from the approximations upon which the computation method is based. The conclusion is reached that both sorts of error are only of minor importance.
DÉTERMINATION DES SALINITÉS DES EAUX DANS LE SOUS‐SOL DU ZUIDERZEE PAR PROSPECTION GÉOPHYSIQUE*
Authors: VOLKER A. , DIJKSTRA J.
Published: April 2006

The paper describes the determination of the chlorine content of deep ground water by means of the direct resistivity method using the Wenner electrode configuration. The purpose was to investigate the distribution of salinity in the brackish waters within a permeable sand of thickness 250 metres and which forms the deeper subsoil of the Ysselmeer areas.

Such a knowledge is of great value, firstly because the seepage of salt water into the proposed deep “polders” may reduce the crop yield, and secondly because it allows areas, where potable waters may occur, to be delineated.

To test the method, measurements were made near existing boreholes which extended to a depth of 350 metres. From these borings water samples from various depths were collected and it was found that the resistivity pl of the porewater was closely related to their chlorine content. The resistivity p of the saturated sand was determined from the geo‐electrical measurements. It was found that the resistivity p was given by p= 4, 5 pl. From this relation, which is independent of the salinity, the chlorine content of the porewater could be estimated. These results are in close agreement with those of other observers. In the area p varied from 1 to 200 ohmmetres corresponding to a chlorine content changing from 12.000 to 15 mg per litre.

The method was adapted for working over water. Each of fourteen insulated conductors in a special cable terminated in an electrode, and these electrodes were spaced along the cable so that nine different Wenner spacings could be selected. The electrode separations varied from 44 metres up to 306 metres.
KONSTRUKTIVE DARSTELLUNG VON SEISMISCHEN HORIZONTEN UNTER BEROCKSICHTIGUNG DER STRAHLENBRECHUNG IM RAUM*
Authors: BAUMGARTE J.
Published: April 2006

The paper describes a geometrical construction which allows the reflecting or refracting Tsoundaries to be derived from seismic time observations.

In reflection work the construction makes use of the ray reflected from the boundary at normal incidence. For constant velocities of the beds, or for a linear increase of velocity with depth, the method leads to the construction of successive envelopes from which the reflecting interface and the rays are obtained. By using the idea of “stretching fictitious rays”, the construction requires ruler and compasses only and is applicable to both plane and curved boundaries with any strike direction and in any number.

The same principles can be applied to refraction problems and again the. construction of successive envelopes allows the indirect or Mintrop wave to be defined. The position of the refracting boundary and the velocity can be derived immediately. As in the reflection method any number of plane boundaries with any strike can be dealt with.

An appendix discusses the use of the method in reflection work with any type of velocity distribution.
ELECTRICAL HAZARDS IN SEISMIC PROSPECTING*
Authors: SELEM A. M. , MERLINI E.
Published: April 2006

Hazards due to powerlines, radiotransmitters and self‐potentials in connection with weather conditions are considered. Voltage and current values are given for several measurements made under the most severe conditions of circuit arrangements. The necessity of general safety precautions is stressed.
A LOW‐FREQUENCY REFRACTION GEOPHONE*
Authors: JONES W. M. , DENNISON A. T.
Published: April 2006

This paper describes a highly portable geophone, designed for large‐scale refraction surveying, which uses a novel suspension system to obtain a natural frequency of about 1.85 c/s. The nominal output is 0.7 volts/cm/second into a 500 ohm load, the damping then being 0.7 of critical. Some typical recorded arrivals obtained with this geophone are illustrated.
DÉTERMINATION DE LA POSITION DANS ĽESPACE D'UN MIROIR SITUÉ SOUS UN RÉFRACTEUR SÉPARANT DEUX MILIEUX DE VITESSES DIFFÉRENTES, À PARTIR DES DONNÉES D'UN TIR EN CROIX ISOLÉ*
Authors: FAVRE B.
Published: April 2006

The problem is considered of how to determine, from dip shooting data, the position in space of a reflecting horizon located underneath a refracting interface between two media of different velocities.

The author proposes a combination between a geometric solution and an analytic one, to obtain the quickest result.
SOME THEORETICAL CONSIDERATIONS ON THE USE OF MULTIPLE GEOPHONES ARRANGED LINEARLY ALONG THE LINE OF TRAVERSE*
Authors: HALES F. W. , EDWARDS T. E.
Published: April 2006

An analytical treatment is given of the response of linear arrays of multiple geophones, as a function of the direction of incidence of the wave and of the wave frequency. The relation between the response and the direction of incidence may be quite complicated, the response being zero in several directions. As a function of wave frequency, the response may also have several zero values within the frequency band in which reflections are expectable. This would result in a serious modification of the filter characteristics of the amplifier. It is shown, however, how such a modification of the filter characteristics may be avoided by a judicious choice of the number and the spacing of the geophones in a multiple group.
TUNIS TO LISBON AIRBORNE MAGNETOMETER PROFILE
Authors: AGOCS W. B. , ISAACS K.
Published: April 2006

Abstract

The results of an 805‐mile (1300 km) airborne magnetometer profile flown across Tunisia and Algeria, from Tunis to the coast west of Oran, across north‐western Spanish Morocco and Tangier, and across south central Portugal to Lisbon are presented. The general geology of the zone over which the profile was flown is shown with the magnetic variations. Depth, structural and rock type interpretations have been made from the magnetic control. The depth values are believed to be high due to angle of the flight line with respect to the probable maximum gradient of the magnetic anomalies. However, depth values are given in all of the basins of possible interest.
APPLICATION OF DELAY AND INTERCEPT TIMES IN THE INTERPRETATION OF MULTILAYER REFRACTION TIME DISTANCE CURVES*
Authors: WYROBEK S. M.
Published: April 2006

The well known quantities, delay and intercept times, can be made fully useful in the interpretation of multilayer refraction problems dealing with small undulating dips.

The identification of the individual refractors is made by the use of reciprocal and intercept times and by applying an additional and useful relationship, namely that the delay time profile between two shot‐points should match the half‐intercept time profile when calculated using the true velocity of the refractor.

With a suitable arrangement of shot‐points this relation permits us to obtain the true horizontal velocity of a refractor from one direction of shooting only.

Presentation of the refraction results in the form of time sections, similar to those used in reflection surveys, is often desirable. These sections can be converted easily into depth sections, once the overburden velocities are defined.

The use of the method is limited not only by the dip, but also by the depth of the refractor. Deep refractors can be, however, worked out by this method, by reducing a multilayer problem to that of two layers, using again the delay times.
SEISMIC EFFICIENCY OF EXPLOSIVES*
Authors: RICHARD Henri , PIEUCHOT Maurice
Published: April 2006

The parameters which characterize an explosive are derived from laboratory tests and none is directly usable for seismic purposes. Another one, derived from field experiments is proposed in this paper. It allows the comparison of two different explosives. The test must be conducted with care. Precautions concerning the equipment and the shot point detailed. The first available results suggest that the new parameter does not depend on the size of the charge nor on the shooting conditions, though the experimental data are not numerous enough to allow a general statement. It is shown how a coefficient of seismic efficiency can be used for selecting an explosive; and considerable amounts of money can be saved by the best choice. More studies on the generation of artificial seismic waves would be highly profitable.
APPLICATIONS OF THE REMANENT MAGNETIZATION OF ROCKS*
Authors: RUNCORN S. K.
Published: April 2006

The basic principles of remanent magnetization are stated, and possible applications are discussed in the fields of age determination of rocks, the study of relative movements of continents, and investigation of the thermal history of rocks.
SCALE MODEL SEISMIC EXPERIMENTS
Authors: HALL S. H.
Published: April 2006

Abstract

An experimental arrangement is described using an electric spark as source and barium titanate as a detector. Model experiments were made in water with the source mounted above the surface. The effect on the pulse shape on transmission through the air‐water interface and the change of pulse shape with depth were investigated. A number of profiles are presented of reflections from a slate slab immersed in the water with different arrangements of the model and detector.
A TORSION‐MAGNETOMETER FOR MEASURING THE VERTICAL COMPONENT OF THE EARTH'S MAGNETIC FIELD*
Authors: HAALCK F.
Published: April 2006

Abstract

The paper describes a vertical component magnetometer for field work whose magnet system is provided with a torsion axis and in which torsion serves as a standard of measurement. When a measurement is taken the magnetic axis of the system is brought back into the horizontal position by altering the angle of twist (null‐method). The angle of twist is thus a direct measure of the vertical intensity. The instrument is within wide limits independent of the magnetic north‐south direction and may therefore be set up in practically any position. The magnet system is temperature compensated, well damped and provided with an automatic clamping device. With a scale value of 25 gammas per scale division the range of the instrument for direct measurements is 65000 gammas. A tripod of special design enables a measurement to be taken in about one minute. The weight of the torsion magnetometer inclusive of tripod is only 2.9 kg (6.4 lb).
CORRELATION OF ROCK DENSITY DETERMINATIONS FOR GRAVITY SURVEY INTERPRETATION*
Authors: WHETTON J. T. , MYERS J. O , SMITH R.
Published: April 2006

The results of field and laboratory methods of density determination on a series of Coal Measure, Permian and Triassic rooks are presented and the different methods compared. It is concluded that the most satisfactory method is that of measuring the vertical change of gravity in a mine shaft. Nettleton's method is unsatisfactory to us, due to weathering of the rocks (particularly Magnesian Limestone) and possible effects from drift. Laboratory measurements are of variable value depending on the lithology and source of the samples.

A method adopted to solve the problem of finding the true densities for use in a local gravity survey in N.E. England is given.
MODERN TECHNIQUE IN SEISMIC REFLECTION RECORDING*
Authors: ANSTEY N. A.
Published: April 2006

This paper is presented to the geophysicist concerned with the taking of seismic records in the field. Part I summarises present knowledge of the fundamental seismic process. Part II details the manner in which this knowledge dictates the selection of some of the parameters available to the operator for controlling the quality of the records. The manner in which the recording problem is changed by the advent of magnetic recording and of automatic record computation is also discussed.
QUELQUES CONSIDERATIONS SUR LES MESURES DE VITESSE EFFECTUEES DANS LES PUITS PAR L'AGIP MINERARIA EN ITALIE ET SPECIALEMENT DANS LA PLAINE DU PO *)
Authors: QUARTA F. , MAINO C.
Published: April 2006

The numerous well velocity measurements carried out in Italy by Agip Mineraria are considered, in an attempt to establish some correlations between the determined velocities and the stratigraphical and lithological characteristics of the formations in which the measurements were made.

The distribution of the seismic velocity is discussed especially in relation to depth, age and lithologic composition of the Tertiary formations in the Po Valley.

Finally, mention is made of some satisfactory results newly obtained on the basis of such considerations, particularly for the delineation of stratigraphic traps.
DIRECT RECORDING VS. FM RECORDING IN SEISMIC TAPE MACHINES *)
Authors: ERATH LOUIS W.
Published: April 2006

This paper describes the two methods of magnetic tape recording used today in the seismic industry. It discusses objectively the characteristics of both methods including historical material, discussion of circuitry, magnetic tape, drive systems, effects of flutter and harmonic distortion, signal transfer and tape transport construction. The paper also includes discussion of noise and reproduction of transient signals. Diagrams illustrating the two recording systems, their frequency response and phase shift characteristics, distortion and noise levels as well as typical wave forms, are also attached.
SEISMIC MODEL EXPERIMENT ON THIN LAYERS*
Authors: CARABELLI E. , FOLICALDI R.
Published: April 2006

Summary

Seismic two‐dimensional model experiments have been made at the Laboratory of Fondazione Lerici in the Polytechnic School of Milan.

For this purpose the Laboratory has developed and constructed a complete equipment including pulse generators, piezoelectric transducers and amplifiers for detecting the waves propagation through the models.

We record here experiments concerning reflections from horizontal layers thin in relation to the wave lengths propagated through the media.

Layers, with a thickness from a 50th of the total wave length to several wave lengths were used. These strata consist of materials sometimes with lower and sometimes with higher velocities than the homogeneous surrounding medium.

The object of this investigation was to clarify the effects of the very thin reflecting layers, individually and in combination, on the reflected arrivals and to determine the influence of the layers upon the reflected energy in comparison with their thickness.

We are also studying at what minimum distance, as a fraction of the wave length, the reflection of a horizon appears on the seismogram in an independent event.
THE PULSED VIBRATOR AS A SEISMIC SOURCE*
Authors: EVISON F. F.
Published: April 2006

Non‐explosive seismic sources, notably the falling weight and the eccentric machine, have occasionally proved advantageous in experimental and practical seismology in spite of their relative feebleness.

Another alternative is the pulsed vibrator, which offers the advantage of a completely controllable waveform. Recent theory shows that such a source is quite well adapted to the radiation of high frequency waves from the surface of the ground; it is estimated, for example, that in typical circumstances reflections should be obtainable from depths of the order of 200 metres. The theory also shows how resonances may be avoided so as to radiate the impulsive waveform unimpaired.
ÉTUDE DE L'ATTÉNUATION DE L'INFLUENCE DES ANOMALIES SUPERFICIELLES DANS LE CALCUL DE LA DÉRIVÉE SECONDE DE LA GRAVITÉ*)
Authors: GOGUEL Jean , LEMOINE Jeannine
Published: April 2006

In order to eliminate the effect of smoothing due to the use of a finite number of grid points, the second derivative is computed by integrating the product of g with a convenient continuous function, which yields the second derivative to the extent to which the first terms of the Taylor expansion of g represent its value correctly. By applying this method to the anomaly caused by an isolated mass, and to that caused by a homogeneous half plane, it is shown that, if the result obtained is interpreted as if it really were a second derivative, erroneous values for the depth and the mass are obtained. If the real depth of the mass is small, a too large apparent depth is obtained. In the case of a half plane the use of a system of grid points gives the same result. These considerations permit the rational choice of the method of computing the second derivative, such that the effects of too shallow mass irregularities are attenuated.
SUR ĽINTERPRÉTATION DES ANOMALIES GRAVIMÉTRIQUES ET MAGNÉTIQUES *)
Authors: DE GERY Jérôme CHASTENET , NAUDY Henri
Published: April 2006

For the interpretation of gravimetric and magnetic maps two types of master curves are proposed: firstly those which apply both to the vertical gradient of g and to the pseudo gravimetric gradient obtained by reduction to the pole of magnetic maps; and secondly those which apply direct to magnetic anomalies.

With regard to the first type of master curve, the principle and the advantages of the reduction to the pole are discussed. In the last part of the paper it is shown how a set of master curves, calculated for two‐dimensional east‐west striking structures, can also be used for the interpretation of two‐dimensional structures of arbitrary direction of strike. Practical examples of application are given.
RADON MEASUREMENTS AS A GEOPHYSICAL METHOD *)
Authors: BUDDE E.
Published: April 2006

Abstract

Faults or Uranium‐bearing veins are often to be found by measuring the Radon‐content of the air in the ground through a layer of porous material, even over some distance.

It is shown by measurements in the laboratory and in the field, that this distance depends on the character of the porous material (composition of grains with different diameters and water content).

A quantitative relation between the composition of grains with different diameters and the coefficient of diffusion of Radon is obtained by comparing the practical measurements with theoretical results.

The result of the investigations is, that Uranium‐bearing veins or faults do not cause any measurable anomaly even over a distance of only 5 cm, if they are hidden under fine‐grained material with its natural water content.
REFLECTION SHOOTING TECHNIQUES IN THE NETHERLANDS*
Authors: SNIJDERS G. H. F.
Published: April 2006

Reflection quality in the Netherlands is extremely variable, ranging from very good to very poor. It is believed that the variation is caused mainly by the changing surface conditions. This suggestion is discussed in the light of available geological data.

Several examples are given showing the usefulness of making broad band recordings on normal reflection spreads.

The combination of data obtained from the study of the surface conditions and from broad band seismograms is used to select the best shooting method.

Some suggestions are made regarding seismometer and shot‐hole patterns, shot medium and the choice of filters.
LA MESURE DE LA VITESSE VERTICALE PAR LE CAROTTAGE CONTINU (CVL); PRECISION DES MESURES ET DISCUSSIONS DE QUELQUES RÉSULTATS*
Authors: SCHWAETZER T.
Published: April 2006

The introduction of the CVL and the “core speed tester” (or ultra sonic velocity meter) have enabled the geophysicist to complement large‐interval, average velocity measurement of sedimentary formations (obtained by conventional well velocity surveys, “Gardner” velocity shots, etc.) by small interval, detailed study of the velocity of particular strata, in situ or in the laboratory. The significance of laboratory velocity measurements on cores is affected by irreversible alterations of the core. At first the integrated time curve of the CVL, calibrated with a skeleton conventional velocity survey, seemed to assure the precision of the interval velocity. Later it was realised that variations of the “Delay Time” (compensation for Mud Travel Time in the single receptor CVL), failure to identify the first energy arrival, etc., could cause errors in the interval velocity measured. These errors can be, detected and reduced by increasing the number of control points of the well survey, running logs down and up the hole, overlapping, and also by the comparison of the Continuous Velocity Logs for neighbouring wells and for various strata in a given well.

Despite these errors, the C VL has been found extremely useful, not only for the determination of average velocity, the identification of reflecting strata, and of refraction markers, but also for geological correlations between wells, the determination of maximum porosity and detailed studies of the parameters affecting the velocity of sedimentary rocks.

The relation between interval velocity and porosity is discussed and a hypothesis that the low velocity of argillaceous, low‐porosity limestones may in part be due to the total fluid contained is put forward.
SYNTHETIC SEISMOGRAMS FROM CONTINUOUS VELOCITY LOGS*
Authors: DÜRSCHNER H.
Published: April 2006

In this paper a method of calculating synthetic seismograms from continuous velocity logs (CVL) is presented and described in detail.

The seismic velocities on the CVL are frequently and rapidly changing. Therefore a seismic field‐record consists of a great number of reflections with different sign and amplitude. The sum of all reflections forms the seismogram.

The first part deals with some relations between the log, the reflection‐layers, and the normal field‐record, with special emphasis on the influence of the seismic amplifier.

Then several assumptions are made for the construction of the synthetic seismograms. Finally some examples and applications are given.
ON REFLECTED REFRACTION WAVES*
Authors: BRAUCH W.
Published: April 2006

As an introduction the various ray paths of a refraction wave, which is reflected at a fault, are discussed for the case of an arbitrary angle between the refracting horizon and the fault. Simple geometric considerations lead to the conclusion that the best chances for recording these pulses are encountered, if the angle between the refracting horizon and the fault is either 90° or the critical angle of refraction. In both cases identical travel times of the pulses are to be expected.

The case of a fault perpendicular to the refracting horizon is considered in detail for dipping beds. Formulas for the shot point travel time curve and the time contour map are derived. Computed time contour maps show considerable differences between the direction of strike of the contour lines and the strike of the fault, as well as between the recorded apparent velocity and the true velocity of the refracting horizon. Finally, alignment charts and computing procedures are given by which the position of the fault and the velocity of the refracting horizon can be obtained from the recorded shot point travel times or the time contour map.
A NOTE ON THE SEISMIC PULSE RECORDED FROM A MINE EXPLOSION
Authors: ANSTEY N. A.
Published: April 2006

It is not easy to record a seismic pulse at distances of interest to oil prospectors without there being reflected or refracted pulses superimposed on the direct arrival. Accordingly the record illustrated is considered worth publishing, although it was taken fortuitously during a normal survey and cannot claim to be a controlled experiment. A comparison with the filtered pulse to be expected from a theoretical Ricker‐type wavelet is presented.
GEOPHYSICAL EXPLORATION IN MINING BY INDUCED POLARIZATION*
Authors: ŠUMI F.
Published: April 2006

Abstract

The present paper deals with various causes giving rise to potential differences caused by induced polarization. In order to obtain the induced polarization effect of ore bodies it is necessary to determine the effect of the barren rock and substract it from the total observed effect.

Results of field measurements carried out by this method in the mercury mine of Idrija, as well as those in the lead‐zinc mine of Mežica and the Kankberg ore district are in good agreement with the geological data. A theoretically calculated profile is compared with an actual field profile.
REMANENT MAGNETIZATION AND THE INTERPRETATION OF MAGNETIC ANOMALIES
Authors: GREEN R.
Published: April 2006

Abstract

Lavas and intrusives are often permanently magnetized in a direction different from the direction of the present geomagnetic field and this can make the interpretation of a magnetic intensity map difficult. However, the profiles over a permanently magnetized body are identical with the profiles over an inductively magnetized body of the same shape provided the direction and dip of the geomagnetic field in the induced case is appropriately changed. In which case, the shape of the body can be deduced by the well‐known methods of interpretation of induced anomalies. Examples of the application of this method to Australian Kainozoic basalts, Tertiary basalts from Australia and Tasmania, and the classical Pilansberg dykes have been worked out. This article stresses the fact that the apparently confused patterns obtained by magnetic surveys over volcanic rocks can often be explained with little difficulty as the juxtaposition of normal and reversely magnetized rocks.
SOME PRESSURE EFFECTS ON THE BEHAVIOUR OF WORDEN GRAVITY‐METERS *
Authors: GANTAR C. , MORELLI C.
Published: April 2006

Abstract

Some tests carried out on a Worden “Educator” gravimeter (n. E 302) showed that pressure variations had a significant effect on the readings.

The changes of pressure cause changes in readings of the same sign. Corrections are given which may be applied to the instrument readings to compensate for this effect.
ANOMALE ULTRASCHALL‐GESCHWINDIGKEITEN IN GESTEINSBOHRKERNEN *
Authors: BAULE H.
Published: April 2006

Abstract

The velocity of supersonic pulses in cylindrical drill cores and rock samples is measured as a function of the frequency or wave length λ of the pulses. If λ is very much lower than the diameter D of the drill core –λ < D– the higher velocity of the longitudinal waves vl appears; on the other side we get the lower velocity of the rod waves vd (Stabdehnungswellen) if λ > D.

Some drill cores from the carbon were found the velocities of which for sonic and supersonic pulses do not follow the above rule. It is shown that these cores have a constant velocity both for short and for long wave lengths in a frequency range between 5 kHz and 2 MHz.
SEISMIC WAVES IN TRANSITION LAYERS*
Authors: BORTFELD REINHARD
Published: April 2006

Abstract

A transition layer is a layer in which the velocity changes linearly with depth from va to ve and we consider it embedded between two layers of constant velocity va and ve, respectively. A plane displacement wave of arbitrary shape is supposed to come out of the upper v”‐layer, and to meet the transition layer at vertical incidence. Using methods of elementary calculus only, the subsequent events are derived for both inside and outside the transition layer.

The transition layer can be regarded as the limit of a sequence of constant‐velocity‐layer divisions. Thus, after computing the first few multiples of the incident wave for these divisions, the respective multiples of the transition layer are obtained as the limit of these multiples. Then, with the help of recurrence formulae, the multiples of the transition layer of any order are computed. The sum of all multiples defines the complete response of the transition layer and satisfies the differential equations of the problem.

The solution has the form of a superposition integral, and it is seen that the transition layer has the properties of a linear filter. The superposition integral is built up out of the incident wave and a conglomerate of Bessel functions, the latter being the corresponding response to an incident spike impulse in a mathematical sense. The reflected and transmitted responses to the spike impulse are shown for two values of the velocity ratio. For large values of this ratio, both these responses have a‘wave‐like’shape and it is seen that the transition layer may effect a serious change of shape of incident waves.
DIFFRACTION PROBLEMS IN FAULT INTERPRETATION*
Authors: KUNZ BRUNO F. J.
Published: April 2006

Abstract

Distinguishing between diffractions and true reflections is often difficult and may lead to misinterpretations. In the Molasse zone of Upper Austria, numerous faults were established by seismic surveying. Diffractions were observed at several antithetic faults but not at synthetic faults. As an example, a seismic record section of the Steindlberg structure is shown. The reflections from the base of Tertiary arid from the Cretaceous‐Jurassic contact run parallel over long distances, and so do the less important reflections lying above and between. If, contrary to the general trend, the reflection from the base of the Tertiary approaches the underlying reflection from the Cretaceous‐Jurassic contact, or if the latter diverges from the former, this is considered a criterion for a diffraction.
THE USE OF AMPLITUDES IN REFRACTION SHOOTING – A CASE HISTORY*
Authors: O'BRIEN P. N. S.
Published: April 2006

Abstract

On a group of seismic refraction records there occurs a late arrival with the same apparent velocity as an earlier arrival. It was first thought that the late arrival travelled along the same refractor as the earlier one but had been delayed in the overburden either by multiple reflection or by P‐S (dilatation to shear) conversion. Either of these two mechanisms could be made to fit the time‐distance data. A study of the ratio of the amplitudes of the two events showed that the observed ratio was about ten times that to be expected on either of these hypotheses. Also, the rate of attenuation of the earlier arrival (3.7 ± 1.0 db/1000 ft) was appropriate to a thin layer while the rate for the later arrival (0.74 ± 0.30 db/1000 ft) was appropriate to a thick layer. Accordingly, the later arrival was identified as a refraction from a deeper layer.

The subsequent depth section agreed very well with that found by drilling.