bluuebunny/crossref_metadata_2025 huggingface dataset:
O-glycans on human high endothelial CD34 putatively participating in L-selectin recognition
Authors: Satomaa Tero , Renkonen Ossi , Helin Jari , Kirveskari Juha , Mäkitie Antti , Renkonen Risto
Published: October 2002

Leukocyte traffic into lymph nodes and sites of inflammation is guided by L-selectin. Experiments performed in vitro and with gene-deleted mice suggest that CD34 recognizes L-selectin if decorated by 6-sulfo sialyl Lewis x (sLex) saccharides and the MECA-79 epitope. However, very little is known about glycosylation of human L-selectin ligands. We report here on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiles of N- and O-linked oligosaccharide fractions from human tonsillar endothelial CD34. All detected O-glycans were sialylated; some were also monosulfated or monosulfated and monofucosylated. If a given CD34-glycan may carry all requirements for L-selectin recognition, that is, both 6-sulfo-sLex and MECA-79 epitopes, only one O-glycan fraction, O-9, SA2Hex3HexNAc3- Fuc1(SO3)1, meets the criteria. A candidate structure is SAα2-3Galβ1-4(Fucα1-3)(6-sulfo)GlcNAcβ1-3Galβ1-3(SAα2-3Galβ1-4GlcNAcβ1-6)GalNAc. However, if sulfo sLex glycans are supplemented with separate sulfated, nonfucosylated O-glycans, saccharides in O-6, O-8, or O-9, putatively carrying MECA-79 epitopes, could form multiglycan binding epitopes for L-selectin.
Maintenance therapy with alternate-day prednisone improves survival in multiple myeloma patients
Authors: Berenson James R. , Crowley John J. , Grogan Thomas M. , Zangmeister Jeffrey , Briggs Adrienne D. , Mills Glenn M. , Barlogie Bart , Salmon Sydney E.
Published: October 2002

The role of maintenance therapy in multiple myeloma is controversial. Recent studies have shown an improvement in both progression-free and overall survival for patients receiving maintenance treatment with a combination of interferon and glucocorticoids, compared with interferon alone. The role of glucocorticoids alone as maintenance therapy has not been previously addressed. We compared alternate-day, oral prednisone at 2 different dose levels (10 mg versus 50 mg) for remission maintenance among previously untreated myeloma patients following a response to induction with standard-dose vincristine, doxorubicin, and dexamethasone with prednisone (VAD-P) or VAD-P plus quinine (VAD-P/Q). There were 250 eligible patients registered on Southwest Oncology Group study 9210 and randomized to receive VAD-P or VAD-P/Q. There were 125 patients achieving at least a 25% tumor reduction following induction therapy who were randomized to either physiologic (10 mg) or pharmacologic (50 mg) doses of alternate-day, oral prednisone until disease progression. At the time of study entry, patient characteristics were similar in VAD-P and VAD-P/Q patients and in the 2 arms randomized to maintenance therapy. After a median follow-up of 53 months, there was no difference in either progression-free or overall survival between the 2 induction regimens. However, from the time of maintenance randomization, both progression-free (14 versus 5 months; P = .003) and overall survival (37 versus 26 months; P = .05) were significantly improved in patients receiving 50 mg as compared with 10 mg alternate-day prednisone. There was no difference in treatment-related adverse events between the groups. Thus, 50 mg, oral, alternate-day prednisone is effective maintenance treatment for multiple myeloma patients who achieve a response to induction chemotherapy.
Antithrombotic effects of controlled inhibition of factor VIII with a partially inhibitory human monoclonal antibody in a murine vena cava thrombosis model
Authors: Singh Inderjit , Smith Alberto , Vanzieleghem Beatrijs , Collen Désiré , Burnand Kevin , Saint-Remy Jean-Marie , Jacquemin Marc
Published: October 2002

The human monoclonal antibody mAb-LE2E9 partially inactivates human factor VIII (FVIII), leaving approximately 10% residual activity. The antithrombotic efficacy of the antibody was evaluated in mouse models of inferior vena cava thrombosis. Thrombi were induced in wild-type mice given either the antibody or saline. No thrombi occurred in any of 8 mice treated with mAb-LE2E9, whereas 6 of 8 control mice developed thrombi (P = .007). Treatment with mAb-LE2E9 did not result in a severe bleeding phenotype: a tail-cutting experiment that resulted in death of C57BL/6 FVIII-deficient (FVIII−/−) mice did not cause hemorrhagic death in mice treated with mAb-LE2E9. To evaluate the antithrombotic effect of mAb-LE2E9 in presence of human FVIII, thrombus formation was induced in FVIII−/− mice reconstituted intravenously with recombinant human FVIII (rhFVIII) or rhFVIII preincubated with mAb-LE2E9. Only 1 of 9 mice produced a thrombus in the rhFVIII/antibody complex–treated group, compared with 7 of 9 in the control group (P = .015). FVIII−/− mice were also reconstituted with rhFVIII and then injected with either mAb-LE2E9 or saline. One of 14 mice in the group treated with the antibody developed a thrombus, compared with 10 of 14 in the control group (P = .001). The thrombi occurring in antibody-treated animals were smaller than in controls (P < .01). All animals survived, and there were no bleeding complications. Thus, the mAb-LE2E9 antibody inhibits thrombosis without causing an overt bleeding tendency.
Significance of the detection of antineutrophil antibodies in children with chronic neutropenia
Authors: Kobayashi Masao , Nakamura Kazuhiro , Kawaguchi Hiroshi , Sato Takashi , Kihara Hirotaka , Hiraoka Asako , Tanihiro Misae , Taniguchi Kikuyo , Takata Noboru , Ueda Kazuhiro
Published: October 2002

We evaluated the clinical characteristics of 41 children with chronic neutropenia based on the quantitative analysis of antineutrophil antibodies in serum by flow cytometry. According to the strength of antineutrophil antibodies, the patients were divided into 3 groups: 12 patients presented negative antibodies, 13 patients showed weak positive antibodies, and 16 patients showed strong positive antibodies. No significant differences were seen in age of diagnosis, severity of neutropenia, and infectious complications associated with neutropenia among the 3 groups. The spontaneous resolution of neutropenia was observed in all patients with negative antibodies and in 22 of 29 patients with positive antibodies. The age of the recovery of neutropenia and the duration until spontaneous resolution of neutropenia were significantly dependent on the antibody strength at the time of diagnosis. These results demonstrate that the quantification of antineutrophil antibodies at the time of diagnosis may be useful in considering the clinical course of chronic neutropenia in childhood.
“Deformation of Rocks under High Confining Pressures. I. Experiments at Room Temperature.” Journal of Geology, Vol. xliv, no. 5, pp. 541–577. By David T. Griggs. (1936).
Authors: Mott‐Smith M.
Published: October 2002

This article describes experiments on the flow and rupture of rocks under compression, tension, and torsion, while at the same time subjected to a high confining pressure supplied through a liquid surrounding the specimen. The hydrostatic pressure of this liquid could be measured very accurately and could be maintained constant. In addition, a “differential” stress was applied to the specimen, and the deformation was measured directly. By using the high pressure technique of P. W. Bridgman the confining pressure was carried up to 13,000 atmospheres, equivalent to a depth in the earth’s crust of 28 miles, and four times that available to F. W. Adams in his pioneering experiments (1901–1917).
“Magnetic Investigations in Southwest Alabama” by J. Brian Eby and E. G. Nicar; Geological Survey of Alabama, Bulletin No. 43, University, Ala. (June, 1936).
Authors: Alder Joseph L.
Published: October 2002

The report covers the results of field work with the Askania‐Schmidt vertical magnetometer done by the junior author. The area worked includes all that part of Alabama lying within sixty‐five miles of the Alabama‐Mississippi boundary between the Gulf of Mexico and the northern portions of Choctaw, Clarke, and Monroe counties. A map of that area, on a scale of three miles to the inch, showing anomaly values in gammas and locations of stations occupied, and contoured on an interval of twenty gammas, accompanies the report.
APPLICATION OF MUD ANALYSIS LOGGING
Authors: Souther Robert E.
Published: October 2002

The mud analysis logging system, now widely used for exploratory and routine drilling, continuously analyzes and records the oil and gas content of mud returns from wells being drilled by the rotary method. Oil or gas detected in the returning drilling fluid indicates oil or gas in the formation penetrated by the bit. Results of the continuous analyses are instrumentally correlated to the depths and formations from which the showings originated. A second useful phase of the system plots accurately and in detail rate of penetration or drilling speed on the log as a function of depth. Trucks and trailers provide a mobile housing for all of the mud analysis equipment so that it may be moved rapidly from well to well. Applications of the method may be divided into two classes: 1. Routine drilling in proved areas where it eliminates unnecessary coring, and locates gas caps and completion zones. 2. Exploratory drilling in which it minimizes coring by indicating for testing purposes porous zones containing oil and/or gas. Mud analysis logging can be practiced in areas where the electrical log cannot be used due to high salt content or other local conditions, where dangerous hole conditions make interruption of drilling operations for coring inadvisable, and for evaluating gas zones where cores are difficult to interpret. In addition, each mud analysis logging unit contains equipment to obtain information useful in eliminating washouts, in predicting and preventing blowouts, and in controlling drilling mud characteristics.
ORGANIZATION OF GEOPHYSICAL PARTIES FOR FOREIGN EXPLORATION
Authors: Dresbach C. H.
Published: October 2002

Current and future requirements of petroleum have produced a strong demand for American personnel, equipment and techniques to be employed in the world‐wide search for oil. Different, and sometimes much more difficult conditions are frequently encountered from those customarily met in the exploration for oil in the United States. A brief consideration of some of these factors is the purpose of this paper. It is concluded that while careful preliminary planning and the design of equipment in the light of accurate information on conditions to be encountered are highly vital factors, the demonstrated and trustworthy character of the personnel conducting the operations is the biggest guarantee of success in the undertaking.
MEASUREMENT OF SOIL‐AIR IONS OVER THE FORT COLLINS ANTICLINE
Authors: Tripp R. Maurice
Published: October 2002

The soil solution is examined for compounds of very low solubility product which might exist in a state of saturation over a large area; some radioactive compounds are found to fill this requirement better than any others. It is postulated that these minerals are preferentially precipitated in the interstices of the near surface soil by the evaporation of the soil water caused by the passage of gaseous hydrocarbons escaping from their subsurface reservoir. Measurements of the rate of formaton of ions in the soil air over a producing structure are presented.
AN INVESTIGATION OF NATURAL EARTH CURRENTS
Authors: Dahlberg R. S.
Published: October 2002

An attempt was made to obtain relative apparent resistivities by measuring the potential gradients produced by natural earth currents. Alternating components in the range 0.5 to 10 cps. were measured. The results of two surveys in Oklahoma are shown and various perturbing factors are discussed. The conclusion is reached that the method is not likely to replace conventional resistivity methods.
GRAVIMETER OPERATIONS IN THE FOOTHILLS BELT OF ALBERTA, CANADA
Authors: Hastings W. K.
Published: October 2002

As part of a gravimeter survey in western Alberta, Canada, the work was extended into quite rugged areas of the Rocky Mountain Foothills belt. This paper outlines the general methods of operation, carried out on horseback from a movable camp, which were employed where conventional methods, using trucks, were impossible. Gravity observations were made with a new, small type Gulf gravimeter which, complete with batteries and other accessories, weighs about forty‐eight pounds. The reduced gravity results were quite smooth and regular in spite of rugged topography and terrain corrections running up to 7 milligals.
REFRACTION EXPLORATION IN WEST TEXAS
Authors: Harris Sidon , Peabody Gwendolyn
Published: October 2002

A brief historical summary of refraction shooting is given, followed by general comments on present “refraction correlation” methods applied to West Texas with special reference to the Edwards Plateau province.
GRAVITY‐METER SURVEY OF THE KETTLEMAN HILLS‐LOST HILLS TREND, CALIFORNIA
Authors: Boyd Lewis H.
Published: October 2002

The gravity anomalies produced by the three Kettleman Hills Domes are maxima. The Lost Hills Anticline produces a gravity minimum. Four maps showing gravity contours, subsurface contours and sections accompany this paper. Maps from a gravity survey over the Kettleman Hills‐Lost Hills Area are compared with previously published subsurface contours and cross sections. These show that the three Kettleman Hills Domes each produce a strong and definite gravity high while the Lost Hills Anticline produces a very clear and closely corresponding gravity low. The paper points out the probable cause of this unusual feature as being a transition within the Reef Ridge Formation from punky, diatomaceous shale at Lost Hills to clays and sands at Kettleman Hills.
ESTIMATING DEPTH AND EXCESS‐MASS OF POINT‐SOURCES AND HORIZONTAL LINE‐SOURCES IN GRAVITY PROSPECTING
Authors: Kogbetliantz Ervand George
Published: October 2002

The problem of the exact quantitative determination of the depth p and total excess‐mass M of a point‐ and a line‐source is solved with the aid of moments of the mapped gravity anomaly [Formula: see text], the correction for the regional anomaly being supposed as already applied. The solution does not presuppose that the constant error E in the regional datum is zero and this error is deduced from the gravity map itself. The relative errors which may affect the given estimates of p, M, E are studied and the magnitude of their upper limits is estimated in the case of a point‐source only since the same analysis can easily be extended to the case of a line‐source. The recommended method of solution reduces the harmful influence of extraneous anomalies from shallow mass points. The details of mathematical proofs are given in an appendix.
THE PREMIUM TECHNOLOGICAL DISCOVERY OF PETROLEUM
Authors: Rosaire E. E.
Published: October 2002

Premium technological discovery volume is that achieved in excess of the volume to be anticipated on the basis of price alone and which can be attributed solely to technological advance. Three degrees of freedom, area, method, and objective, are recognized for the prospector, and these are fixed by choice in any prospecting venture. Continued operation with these three degrees fixed inevitably leads to diminishing returns and, finally, to marginal operations wherein price becomes the primary motivation. Under such conditions in the past, unfixing even one degree of freedom has led to marked surges in the discovery rate, i.e., to premium technological discovery. Such discovery surges have occurred more than once in the same petroleum province and, not infrequently, the magnitude of the surge has increased rather than decreased with time. Considerations are presented for a return to premium technological discovery within the United States. Such a return for the method now in most general use, the reflection seismograph, can be expected to follow from unfixing the area degree of freedom through initiating prospecting along the continental shelf. However, such a return for prospecting as a whole, and probably of even greater magnitude, can be anticipated to follow from unfixing the method degree of freedom through widespread application of novelty in prospecting methods.
THE PLANNING OF A FOREIGN GEOPHYSICAL OPERATION
Authors: Dawson Herbert M.
Published: October 2002

This paper contains a discussion of the advance preparation necessary for a properly conducted foreign geophysical operation. Consideration of the economic factors involved emphasizes the necessity of having proper equipment and an efficient supply system.
A RESISTOLOG SURVEY OF THE LOMA ALTO‐SEVEN SISTERS AREA OF McMULLEN AND DUVAL COUNTIES, TEXAS
Authors: West Thomas S. , Beacham Clarence C.
Published: October 2002

Additional Resistolog field data are shown. This survey is in the Loma Alto‐Seven Sisters area of McMullen and Duval Counties, Texas. The subsurface geology of this area is also shown along with an electric log cross section to which Resistologs have been added. Four of the apparent resistivity curves employed for calculating Resistologs are included for demonstrating the relatively great extent to which apparent resistivity may be influenced by shallow inhomogeneities along a traverse of electrodes which are moved for securing a variation in electrode separation. Several cases of direct detection of oil and gas saturation and successful structural correlations are presented.
INDEX OF WELLS SHOT FOR VELOCITY
Authors: Swan B. G.
Published: October 2002

The information listed on velocity surveys in 167 wells is in the nature of a supplement to the “Index of Wells Shot for Velocity” published in the October 1944 issue of Geophysics. In addition to the new surveys listed, corrections and information missing on many of the surveys of the original Index are tabulated.
A DIVING BELL FOR UNDERWATER GRAVIMETER OPERATION
Authors: Frowe Eugene W.
Published: October 2002

The recent development of a diving bell, designed to carry a gravimeter and observer, enables the geophysicist to make correct gravity observations on a river, lake or ocean floor. The bell, for which patents have been applied, is designed to operate in depths of water as great as 250 feet. It has been used with good results at depths ranging from 8 to 70 feet. Data taken from adjacent land and sea areas have been contoured and the smoothness of the resulting contours indicates that the underwater gravity readings are entirely reliable. Structural features of the diving bell and related equipment are described and plates showing exterior and interior views of the bell are given.
QUANTITATIVE ASPECTS OF JUXTAPOSED OCEAN DEEPS, MOUNTAIN CHAINS AND VOLCANIC RANGES
Authors: Gunn Ross
Published: October 2002

Continuing earlier explorations of the geological consequences of a strong elastic lithosphere supported on a weak magma, the mechanical characteristics of a shear thrust fault are examined. Due principally to the differential cooling of the continental and oceanic areas and the higher standing of the former, continental boundaries are regions of potential weakness and the lithosphere there is subject to shear failure with resultant over‐thrusting of the continental sector when sufficiently compressed by horizontal forces. The deformations of such a compressed and fractured lithosphere and the fibre stress distribution therein are quantitatively worked out, permitting the determination of maximum depths, heights, widths, figures, gravity anomalies, and fibre stresses. These estimated quantities are found to be strikingly similar to the properties of a geological area on the western coast of Mexico that exhibits juxtaposed ocean deeps, mountain and volcanic chains. The reasons for the simultaneous existence of these remarkable earth features and their special relation to each other are shown to follow immediately from the mechanical characteristics of the lithosphere. The existence of volcanic activity only in regions where there is a definite tendency for the bottom of the lithosphere to be in tension gives a valuable clue as to the basic mechanisms responsible for volcanic activity.
CASE HISTORY OF THE FORT COLLINS EXTENSION, LARIMER COUNTY, COLORADO
Authors: Wilson John H.
Published: October 2002

The results of a gravity meter survey of the Fort Collins field, Larimer County, Colorado, both before and after elimination of regional effects, is presented together with subsequent seismograph and subsurface studies which led to the development of a small northward extension of the Fort Collins oil field. Other geophysical work in the area is reviewed.
A RECORDING SIX‐TRACE CATHODE‐RAY OSCILLOGRAPH
Authors: Shepard, Ward , Beyer, G. L.
Published: October 2002

A portable, general purpose six‐trace cathode‐ray oscillograph is described. Eight 2-inch cathode‐ray tubes are arranged side by side in a line. Six of these tubes have individual d.-c. amplifiers with high gain, high input impedance, good high‐frequency response, and excellent stability. The two outside cathode‐ray tubes provide calibrated timing pulses. A removal camera with a fast lens photographs the cathode‐ray tubes on 35-mm. film, to give a continuous displacement‐time record of the cathode‐ray spots. The film may be driven past the lens aperture at speeds continuously variable from a few inches per second to 13 feet per second. A 100-foot film supply system can be used, or a 10-inch strip can be fastened around the drive drum for short records. Film can be processed rapidly, and readily examined with a viewer having a 5 to 10 diameter magnification. More complete analysis of records can be made from enlargements.
MICROSEISMS IN NEW ENGLAND—CASE HISTORY OF A STORM
Authors: Leet L. Don
Published: October 2002

A microseismic storm recorded at the Harvard Seismograph Station November 14–16, 1945 is analyzed. Associated meteorological conditions are described. Rayleigh waves and Q‐waves are identified. Rayleigh waves are used to determine the direction of approach of the microseisms. It is found that the microseisms did not radiate from the center of the barometric low and that at the height of the storm they approached the station from several directions. The position of the cold front associated with the storm correlated better than that of the barometric low with the directions from which microseisms were observed.
REMARKS REGARDING MULTIPLE REFLECTIONS
Authors: Johnson Curtis H.
Published: October 2002

These comments and illustrations are designed to show that in Butte County, California, at least, multiple reflections do exist. When to suspect them and how to evaluate the probability of their existence is discussed in the light of examples from this area.
PRELIMINARY RESULTS OF A STUDY OF SEISMOGRAPH SENSITIVITY REQUIREMENTS
Authors: Haggerty P. E. , Olson R. W.
Published: October 2002

The ambient ground‐noise level is one of the most important factors in determining sensitivity requirements for a seismograph system. This paper, on the basis of eighty‐one measurements in three areas in Texas, concludes that for these areas minimum ambient noise levels (in terms of particle velocity) of the order of 3 to 5 millionths of an inch per second are common. Assuming a seismometer sensitivity of 2 volts per inch per second and an oscillograph sensitivity of 5 inches per volt, an overall gain of 20,000 from the output of the seismometer to the input of the oscillograph would be required to give a one‐half‐inch peak‐to‐peak deflection from a noise signal with a peak‐to‐peak particle velocity of 2 1/2 millionths of an inch per second.
DEEP ELECTRICAL PROSPECTING—A DISCUSSION
Authors: Yüngül Sulhi
Published: October 2002

In two papers published in Geophysics, one in the October, 1944, issue and the other in October, 1946, a system and method of calculation, called “Resistolog” method, was presented. The object of the Resistolog method is to eliminate the effects of superficial inhomogeneities which are the most troublesome obstacles in interpreting electrical sounding results in exploring deep, horizontal discontinuities. The following is a discussion of the papers mentioned above, mainly of the subject of (1) the apparent‐resistivity formula derived for use with the Resistolog configuration, (2) determination of inflectional points on apparent resistivity curves, (3) depth of penetration, and (4) distortion caused by the “far electrode.” A new method to determine inflectional points is also given. This paper includes a comprehensive knowledge about the forementioned papers and the reader may not have to refer to them.
DEEP ELECTRICAL PROSPECTING—A REPLY
Authors: West Thomas S.
Published: October 2002

Mr. Yüngül’s review of the “Resistolog” procedure has been read with interest. The primary reason for publishing Resistolog data was the hope that a mathematical explanation for the observed phenomena would result. Mr. Yüngül’s paper is most welcome inasmuch as it represents an effort in the desired direction.
A TOTAL FIELD MAGNETOMETER FOR MOBILE OPERATION
Authors: Frowe Eugene
Published: October 2002

A magnetometer which measures the earth’s total magnetic field is described. The detector or measuring element of the magnetometer contains three mutually perpendicular elements, two of which are utilized to orient the third, which in turn operates a recording device to record the total magnetic field. The detector elements are of the inductive type and do not require ferromagnetic material to give them the high sensitivity required in geophysical work. The presence of a magnetic field in the region of the detector causes alternating currents to be generated in the detector elements. These currents are amplified to actuate motors which control the orienting and neutralizing functions of the magnetometer. A tape recorder gives continuous field readings. The accuracy of the magnetic data taken is better than five gammas.
GRAVITATIONAL TERRAIN EFFECTS OF TWO‐DIMENSIONAL TOPOGRAPHIC FEATURES
Authors: Hubbert M. King
Published: October 2002

If terrain corrections are not systematically made when conducting gravity surveys, it is a matter of some importance to locate stations away from points for which this effect is a maximum. While this fact is fully appreciated, our literature is deficient in information that a field man could use telling him how large would be the effect of a given topographic feature, or how far away the station should be placed to keep the error within prescribed limits. To meet this need continuous profiles of terrain effects across 47 different forms of two‐dimensional topography have been computed and are presented herewith. These are expressed dimensionlessly so that each figure represents an infinite class of features having the same shape. In addition, the profile for each ridge is also valid for valleys of the same form, but inverted. The data thus are applicable to a double infinity of cases. These profiles are also useful to the interpretive staff for determining quickly whether certain small anomalies are significant, or whether they are more probably the result of local uncorrected terrain.
INTEGRATION IN EXPLORATION
Authors: Green Cecil H.
Published: October 2002

It is a particular privilege to address not only geologists, paleontologists, and geophysicists of the petroleum industry, but also a group of specialists in mining exploration. To you who are mining geophysicists, I hope that I am correct in assuming that the philosophy of my discussion does have a considerable bearing also upon the search for new ore deposits, even though colored by constant reference to petroleum.
SOME ASPECTS OF ORE DEPOSITS IMPORTANT IN GEOPHYSICAL WORK
Authors: Schwartz George M.
Published: October 2002

The application of geophysics to mining problems is much more difficult than is the case with the petroleum industry. The fundamental contrasts between the occurrence of petroleum and ores are outlined. Difficulties arise because of the great complexity and variation in occurrence and size of deposits of commercial metallic and non‐metallic minerals. These complexities are discussed and illustrations cited in terms of mineralogic, petrographic, structural, and genetic variations in ores. The relatively large horizontal extent of petroleum deposits, as compared with many mineral deposits is emphasized. One of the important problems in the application of geophysics to ore‐finding is determining the definite relation of ore to specific geologic features, so that the results of geophysical work can be interpreted in terms of the probable location of more ore. This is essentially a geologic problem, and one not easily solved in many districts. For the successful application of geophysics and interpretation of the results, a very detailed knowledge and understanding of the geology is fundamental. Also additional geophysical methods are required, particularly those which might locate ore directly rather than indirectly through the geology as is largely the case in petroleum. Because of the complexities involved, no one method should be considered a true test of an area but several methods should be utilized. Much more extensive and intensive application of geophysics to problems of ore‐finding, as well as new methods are demanded by the rapid depletion of present ore reserves.
THEORY AND PRACTICE OF LOW‐FREQUENCY ELECTROMAGNETIC EXPLORATION
Authors: Evjen Haakon M.
Published: October 2002

Based directly on Maxwell’s Field Equations, the extremely low end of the frequency spectrum may be reduced in first approximation to simple potential theory. The approximation theory is borne out by some field experiments, the results of which are presented. Agreement with the theory, however, requires that the ground have a very large effective dielectric constant. This conclusion is supported by previous observations by a number of independent observers. Thus, the relaxation time has been found to be extremely great, not only in observations directly on the ground, but also in small samples of mud, and the sign of an electric anomaly over a relative insulator, such as crystalline salt or gas and oil, invariably has been found to be negative. Both of these observations can be explained in terms of a very great dielectric constant. The value yielded by the present experimental work is of the order of [Formula: see text].
BIOGEOCHEMICAL INVESTIGATIONS IN BRITISH COLUMBIA
Authors: Warren Harry V. , Delavault Robert E.
Published: October 2002

Biogeochemistry, like geophysics, is a useful tool for those who seek ore in areas where outcrops are few, vegetation heavy, or glacial drift widespread. Knowledge of the normal amounts of, as well as the ratios existing between, any elements in the selected organs of appropriate trees and lesser plants growing under the various geological and geographical conditions involved in a chosen area, makes it possible to discover biogeochemical anomalies should any be present. Experience in British Columbia suggests that in a search for copper or zinc, a study of the ratios existing between the amounts of these elements present in young twigs affords a simple and usually effective way of detecting anomalies. By using twigs, it is practical to carry on investigations during seasons when weather conditions make some types of prospecting impossible. Biogeochemistry is not a rival of geophysics, geology, or hard work as a means of finding ore. It is another tool which, if employed intelligently under appropriate but not necessarily ideal conditions and in conjunction with other suitable tools, can do much to assist in a search for hidden ore.
STUDIES IN FAULT DETECTION WITH THE REFLECTION SEISMOGRAPH
Authors: Kelsey Martin C.
Published: October 2002

Faulting has long been recognized as an important factor in the formation of traps for the accumulation of oil and gas. A discussion is presented of some of the problems connected with fault interpretation, together with suggestions as to methods which may be employed to assist in the solution. Field data and final fault interpretation of a peculiar problem are herein illustrated.
A DISCUSSION OF STEEP‐DIP SEISMIC COMPUTING METHODS
Authors: Rice R. B.
Published: October 2002

This paper presents a comparison of the results obtained by the application of several standard computing techniques to the computation of steep‐dip seismic data. Formulas for the horizontal displacements and depths of reflection points are derived for the various methods, assuming velocity to be a parabolic function of depth, and the results obtained for a typical velocity function over a wide range of reflection and stepout times are compared graphically. In addition, the overall effect of applying these methods to the computation of a specific steep‐dip asymmetric structural profile is studied.
CORRELATION POSSIBILITIES IN THE SACRAMENTO VALLEY
Authors: Cohick K. S.
Published: October 2002

Several years ago while doing routine seismic shooting in a portion of the Sacramento Valley near the town of Elk Grove, several prominent reflection bands were noticed recurring on many of the profiles. Five selected profiles are shown in discussing reflection correlation over this small, comparatively ideal area. Figure 1 shows the general location of the profiles which range from 2 to 8 miles apart. Figure 2 shows three records whose location can be seen by referring to Figure 1. Records 1, 2, and 3 were correlated as shown by events A and B. When the B events are correlated as shown, there is some evidence that in going from record 2 to 3 the A event could correlate with A′. However, when the records are studied more carefully, it appears that the interval between reflection bands thickens and that the events A and B should be correlated as marked on all three records. This correlation was independently substantiated by connecting continuous profile lines. It would appear then that between these three records, jump correlation might be done with a fair degree of accuracy.
A PRECISION DETAIL GRAVITY SURVEY, JAMESON AREA, COKE COUNTY, TEXAS
Authors: Brown Hart
Published: October 2002

Since few, if any, conventional gravity surveys of the Jameson Area produced a significant gravity anomaly, an experimental high density gravity survey was conducted immediately following the field discovery. A station density of 15 per square mile was achieved. Great pains were taken to obtain higher than customary precision of each field measurement. Careful terrain corrections were applied. Maps of observed and residual gravity are presented. The subsequent drilling of some 36 field wells now provides an accurate reef map. This reef map is compared with the gravity anomaly to bring out the degree of correlation which may be expected from other similar reefs.
ANNUAL SURVEY OF GEOPHYSICAL EDUCATION 1949–1950
Authors: Macelwane James B.
Published: October 2002

A brief questionnaire was circulated to all those institutions of higher learning who had signified their interest in any form of geophysical education by their replies to the more elaborate enquiry sent to all institutions last year. The positive answers received are best shown by means of the following tabulations. Comparison with the results of the previous year’s survey indicates a steady growth in all phases of geophysical education but especially in the field of geophysical exploration.
ELECTRIC LOGGING APPLIED TO GROUND‐WATER EXPLORATION
Authors: Jones P. H. , Buford T. B.
Published: October 2002

A method is described for the determination of the quality of ground water in granular aquifers penetrated by rotary‐drilled holes electrically logged. Conventional techniques of electric‐log interpretation, to determine true bed resistivity from apparent resistivity values, are briefly described; and a method for converting water‐resistivity values into hypothetical chemical analyses is explained. The objective of the method is to narrow the limits of error in quality‐of‐water estimates based upon electric logs. Water‐well contractors are fully aware of the risks attendant in making drill‐stem tests in open hole, which is the method now employed to obtain representative samples of formation water. Packer failure results in contaminated samples; hole collapse may mean loss of drill stem, screen, and the hole. In the Gulf Coast where water‐well tests range in depth from 100 to 3,000 feet, methods that will eliminate at least a part of the need for drill‐stem tests deserve consideration. The paper deals also with methods of determining formation porosity in situ, which is an important factor in salt‐water‐encroachment problems.
CASE HISTORY OF BENTON FIELD, BOSSIER PARISH, LOUISIANA
Authors: Valerius C. N. , Von Croy Stefan
Published: October 2002

A regional gravity‐meter survey executed during the summer of 1943 along the eastern slopes of the Sabine uplift indicated the presence of a prominent minimum trend. The first traverse of a subsequent reflection seismograph survey in portions of Townships 20 and 21 north, Ranges 12 and 13 west, Bossier Parish, Louisiana, revealed strong critical west and north dips, after which the Benton structure was delineated by a moderate amount of seismograph work. Geophysical maps of the raw gravity configurations and two seismic control horizons are presented. A comparison of the base of the anhydrite control with the deeper seismograph horizon, later identified to be somewhat below the Bodcaw sand of the Cotton Valley series, demonstrates the shifting of the structural axes down dip with increased depth. The discovery well on the apex of the structure and 16 other development wells confirm the outline of the seismic Cotton Valley picture. The structure is an elongate anticline approximately seven miles long with an average width of two and one‐quarter miles. Although only 60 feet of closure on the “D” sand has been proven by drilled wells, it is evident that total closure must exceed 100 feet. The history of folding of the Benton structure reveals interesting comparison of the results of the local causative forces as opposed to the effects of regional tilting due to the Sabine uplift. The remarkable accuracy of the seismic data was chiefly responsible for the unusual development following discovery of the field which resulted in early unitization of leaseholds which later included mineral and royalty interests. This permitted very economical drilling costs and proper spacing and location of wells to secure efficient drainage.
GEOPHYSICAL HISTORY OF THE DELHI FIELD, RICHLAND, FRANKLIN, AND MADISON PARISHES, LOUISIANA
Authors: Hollingsworth W. E.
Published: October 2002

The geophysical history of the Delhi Field started in 1938 when a Gulf gravity crew entered the area. In early 1940 results of drilling to the east indicated the absence of Tuscaloosa beds and a possible pinchout. In 1944, a seismograph crew under contract to Sun Oil Company and C. H. Murphy entered the area. A small closure was found and drilled. Production was established in 1944 from Paluxy beds.
GEOPHYSICAL ACTIVITY IN 1950
Authors: Eckhardt E. A.
Published: October 2002

When we reviewed the geophysical activity of 1949 at our meeting last year, we looked back on a considerable decline in the United States from a high of 520 seismograph crew‐months in November, 1948 to a low of 416 in February, 1950, the last month for which information was then available. We did not know at the time whether the decline would continue and, if so, how far. The atmosphere was one of concern. We noted, however, that economic and other factors strongly indicated an early reversal and the future surpassing of earlier peaks.
SEISMIC SOUNDINGS OF GLACIERS
Authors: Poulter Thomas C.
Published: October 2002

Because of the ever‐expanding field of activity of the geophysicist and the important contribution that can be made by seismic techniques to research in the polar regions, it is felt that the material contained in the review of the activity of the Swiss Glacier Commission, published in 1948, should be brought to the attention of American geophysicists. I have therefore prepared the following condensed translation of the paper by A. Renaud and P. L. Mercanton. I feel from experience gained in the Antarctic and on Taku Glacier (Alaska) that with the recent developments in modern portable electronic seismographs more reliable information can be obtained with these units using air shooting and at no increase in weight even for a 12-channel unit.
SEISMIC RECORD SECTIONS
Authors: Prescott H. R.
Published: October 2002

A method is described whereby seismic records may be secured which have sufficient dimensional stability that a composite reprint of several records, from a continuous profile, when placed in proper sequence, yields a cross section of seismic arrivals. A method is described for entering corrected time scales on the seismic record section itself. Double recording is provided, with traces in transposed positions but alike in phase relation, which makes possible the construction of closed traverse sections. A few examples of the record section are shown and some uses suggested.
THE RECENT PROGRESS OF THE GRAVITY PROGRAM OF THE COLUMBUS GROUP
Authors: Hirvonen R. A.
Published: October 2002

The world‐wide gravity program of the Mapping and Charting Research Laboratory of Ohio State University has been described for this society at the last annual meeting by Dr. W. Heiskanan, who was invited by Prof. G. H. Harding, director of the laboratory, to plan this program and to function as the scientific leader for its realization.
RELATION OF SEISMIC CORRECTIONS TO SURFACE GEOLOGY
Authors: Thralls H. M. , Mossman R. W.
Published: October 2002

The arbitrary application of any set type of near‐surface corrections to seismic data can lead to erroneous results. The determination of the type of correction to be used must be based, in part, on the type of formations present in the near‐surface. Case studies are offered to illustrate conditions arising in areas of youthful and mature topography. Specifically, they deal with a complex low velocity layer problem in a river valley, a pre‐glacial topography in the Illinois Basin, a problem arising in a mature topography in Kansas, and a youthful topography in central Wyoming. In such cases, the use of a “floating” elevation reference plane is advocated for the “Correction Zone” lying immediately below the surface.
EXPLORATION PROBLEMS OF THE WILLISTON BASIN
Authors: Burg K. E.
Published: October 2002

Discovery of oil in North Dakota by the Amerada Petroleum Corporation in their Clarence Iverson well in the vicinity of the Nesson Anticline, near the center of the Williston Basin, initiated a very active exploration program covering the entire basin. Interest in the area has continued because many of the wells drilled in other portions of the basin have resulted in discovery of oil in commercial quantities. Because of the wide regional extent of the Williston Basin and presence of a rather complete Mesozoic and Paleozoic section, many exploration problems are encountered. The role of the seismograph in the solution of these problems is discussed.
MAGNETIC SUSCEPTIBILITY MEASUREMENTS IN MINNESOTA PART I: TECHNIQUE OF MEASUREMENT
Authors: Mooney Harold M.
Published: October 2002

Susceptibility determinations have been made on 200 outcrops of 11 rock types, using a three‐coil induction instrument. Measurement is effective over a hemisphere of 50 cm radius. Data are given to show that the instrument is much less sensitive to rock surface irregularities than any previously described. Measuring circuits consist of 975 cycle oscillator, mutual inductance bridge, and two‐stage amplifier. Investigation of errors shows that surface irregularities remain most important. Calibration by calculation is checked against ferric chloride standards through small samples taken at each outcrop. Data are given to show: 1) rock variability makes the check inconclusive, 2) variation of susceptibility within outcrops for gabbro and basalt is of the same order as variation between outcrops, 3) small‐sample measurements show greater variation than large‐sample measurements.
THREE DIMENSIONAL INTERPRETATION OF GRAVITATIONAL ANOMALIES, PART II
Authors: Grant Fraser S.
Published: October 2002

This is the second of two papers describing a method of interpreting residual gravitational anomalies in terms of three‐dimensional geological structures. This paper describes an analytical method for smoothing the data, and for constructing charts and templates for computing derivatives and other quantities required in the interpretation formulae already given in Part I. Tables of all quantities required for the practical utilization of this procedure are provided. Two examples of the application of these methods are given: the first, an artificial problem, and the second, an actual survey conducted over a sulphide body that has been outlined by extensive drilling.
LIMITATIONS OF THE SEISMIC METHOD OF MAPPING FAULTS
Authors: Romberg Frederick
Published: October 2002

The limitations inherent in the seismic method of mapping faults are listed and classified. These limitations are divided into instrumental, physical, and geological. An attempt is made to treat them quantitatively and to find places where the accuracy of the seismic method can, or cannot, be improved in the foreseeable future. Attention is called to the fundamental assumptions of seismic prospecting, the prevalence in practice of contradictions of these, the inability of present methods to do what is expected of them, and the difficulty of checking their results. The role of non‐structural prospecting is considered, on the basic of specific failures in current methods. A general equation for dealing with horizontal velocity changes is suggested in an appendix.
USE OF THE WAVE HEIGHT OPERATIONAL INDEX IN PLANNING OFFSHORE GRAVITY METER SURVEYS
Authors: Glenn A. H. , James R. W.
Published: October 2002

Efficiency of offshore gravity meter exploration (stations occupied daily) is analyzed statistically as a function of wave height. For the surveys investigated, the number of stations occupied daily can best be represented by the line of regression, Yc=49.85−8.75X, where X equals wave height (as defined herein), and Yc equals number of stations. Cost of offshore gravity meter surveys is shown to vary as much as 50 percent depending on planning involving sea conditions. Application of forecasts of sea and weather conditions is discussed and savings achieved through their use are demonstrated.
APPARENT RESISTIVITY CURVES FOR DIPPING BEDS
Authors: Unz M.
Published: October 2002

The apparent resistivity calculations published for the two layer case with an inclined interface can be applied to small dip angles only. They are also limited to low ratios of the electrode spacing in relation to depth. This investigation covers the complete range of dip angles and electrode spacings. The theory of reflected images is not generally applicable to the case of dipping layers, as assumed until now. Only for certain particular values of the dip do the methods of this theory remain in force. For all other dip angles practically sufficient results are obtainable by interpolation. The calculations are exact in cases with a bottom layer of very high or negligibly low resistivity. For the intermediate resistivity values an approximation method is available. Simple algebraical expressions are obtained for the apparent resistivity curves. An approach to multilayer problems is discussed. The field procedure is outlined.