scholarly journals The Effect of Glacial Cross-Section on Vertical Resistivity Depth Soundings

1973 ◽  
Vol 12 (66) ◽  
pp. 375-382 ◽  
Author(s):  
R. W. Taylor ◽  
R. J. Greenfield
Keyword(s):  
Cross Section ◽  
Field Data ◽  
Apparent Resistivity ◽  
Ice Thickness ◽  
Master Curves ◽  
Glacial Ice ◽  
Resistivity Measurements ◽  
Oriented Parallel ◽  
Wenner Array

The determination of glacial ice thickness by vertical resistivity depth soundings relies upon the use of theoretical curves which neglect the effect of valley walls. To improve the utility of glacial resistivity measurements an analytical expression is derived for the apparent resistivity determined by a Wenner array oriented parallel to the strike of a layered trough embedded in a perfectly conducting half space. Numerical evaluation of this expression allows the effects of glacial cross-section to be determined. It is shown that the presence of valley walls and layering within the glacier can strongly effect the determination of total ice thickness, and a criterion for the reliable use of plane-layered master curves in the interpretation of field data is established. An apparent resistivity curve calculated for a layered trough is shown to give an excellent fit to field data published by Röthlisberger and Vögtli (1967).

The Effect of Glacial Cross-Section on Vertical Resistivity Depth Soundings

1973 ◽  
Vol 12 (66) ◽  
pp. 375-382
Author(s):  
R. W. Taylor ◽  
R. J. Greenfield
Keyword(s):  
Cross Section ◽  
Field Data ◽  
Apparent Resistivity ◽  
Ice Thickness ◽  
Master Curves ◽  
Glacial Ice ◽  
Resistivity Measurements ◽  
Oriented Parallel ◽  
Wenner Array

The determination of glacial ice thickness by vertical resistivity depth soundings relies upon the use of theoretical curves which neglect the effect of valley walls. To improve the utility of glacial resistivity measurements an analytical expression is derived for the apparent resistivity determined by a Wenner array oriented parallel to the strike of a layered trough embedded in a perfectly conducting half space. Numerical evaluation of this expression allows the effects of glacial cross-section to be determined. It is shown that the presence of valley walls and layering within the glacier can strongly effect the determination of total ice thickness, and a criterion for the reliable use of plane-layered master curves in the interpretation of field data is established. An apparent resistivity curve calculated for a layered trough is shown to give an excellent fit to field data published by Röthlisberger and Vögtli (1967).

scholarly journals Assessment of 2-D resistivity structures using 1-D inversion

Geophysics ◽  
1991 ◽  
Vol 56 (6) ◽  
pp. 874-883 ◽  
Author(s):  
L. P. Beard ◽  
F. D. Morgan
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Apparent Resistivity ◽  
Inversion Process ◽  
Square Prism ◽  
Contour Lines ◽  
The Cross ◽  
Schlumberger Array ◽  
Wenner Array

Schlumberger and Wenner array resistivity soundings over 2-D resistivity structures are interpreted using apparent resistivity pseudosections and cross‐sections constructed from 1-D inversions in order to determine the effectiveness of 1-D interpretations over such structures. Cross‐sections contoured from resistivities of inverted “layers” show distinct differences from the apparent resistivity pseudosections and may be used as interpretational aids. Contour lines in the cross‐sections locate the horizontal interfaces of the 2-D structures quite well. The vertically oriented segments of the cross‐section contours are relatively undistorted in the inversion process and are similar to the vertically oriented portions of contours in the apparent resistivity pseudosection. A simple, empirically determined formula is used to separate the sections into resistive and conductive zones and helps to define the geometry of the anomaly. In order to apply the formula, it is necessary to know whether the target is a relative conductor or a relative resistor. Except for the case of a square prism, the Schlumberger array appears to hold advantages over the Wenner in qualitatively assessing an anomaly. The primary drawback of the Wenner array is that its expanding potential electrodes create false anomalous zones and complicate interpretation. As might be expected, structures with long horizontal interfaces, i.e. those more nearly 1-D, yield the most accurate interpretations.

Discussion of paper by A. R. Clark entitled “The Determination of the Long Dimension of Conducting Ore Bodies”

Geophysics ◽  
1956 ◽  
Vol 21 (2) ◽  
pp. 477-478
Author(s):  
Bruno Kunz
Keyword(s):  
Apparent Resistivity ◽  
Semimajor Axis ◽  
Electrode Spacing ◽  
Logarithmic Scale ◽  
Master Curves ◽  
Resistivity Ratio ◽  
Ore Bodies ◽  
The Absolute ◽  
Short Time

When J. N. Hummel published his first apparent resistivity curves some 30 years ago, he used coordinates with a linear scale. A short time later it was found that such master curves are universally usable only when plotted on logarithmic scales. The reason for this is that the shape of the curves does not depend upon the absolute electrode spacing and the absolute resistivity values but only on the relative values. This, naturally, also holds true for the examples shown by A. R. Clark. The curves as shown by him reveal a resistivity ratio of [Formula: see text]. In the same way, the “Distance as a fraction of the Semimajor Axis” is a quotient. Both coordinates should therefore be presented in a logarithmic scale. When so plotted, the characteristic properties of the curves are much more conspciuous and are very different from those when linear scales are used. The remarks made by the author relative to the shape of the curves may have to be revised.

A RESISTOLOG SURVEY OF THE LOMA ALTO‐SEVEN SISTERS AREA OF McMULLEN AND DUVAL COUNTIES, TEXAS

Geophysics ◽  
1946 ◽  
Vol 11 (4) ◽  
pp. 491-504
Author(s):  
Thomas S. West ◽  
Clarence C. Beacham
Keyword(s):  
Cross Section ◽  
Field Data ◽  
Apparent Resistivity ◽  
Oil And Gas ◽  
Direct Detection ◽  
Gas Saturation ◽  
Subsurface Geology ◽  
Electrode Separation

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.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Mekanisme Dan Proteksi Jaminan Nasabah Pada Gadai Informal

Liquidity ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 103-109
Author(s):  
Yuri Nanda Larasati ◽  
Jafril Khalil
Keyword(s):  
Qualitative Research ◽  
Research Methods ◽  
Financial Services ◽  
Field Data ◽  
Qualitative Research Methods ◽  
Research Field ◽  
Consumer Society ◽  
Library Research ◽  
The Cost

Regulation of the financial services authority (OJK) No. 31/POJK.05/2016 on Venture had arranged that the financial services agency on the basis of the law of pledge is in coaching and supervision OJK. Yet the existence of laws – invitation to Governing Enterprise pawn shops causing business activities conducted by the above parties are not yet regulated. The condition is feared could cause harm to the consumer society. The purpose of this research is to know the procedures, mechanisms, protection of goods and guarantee the consumer on an informal pledge financing, methods of determination of the cost of maintenance of the goods and the goods of the execution mechanism of the pledge as well as protection for the collateral items are viewed from the side of the consumer by looking at laws-invitations and Sharia. To find out whether the pledge have gotten permission from OJK. This research uses qualitative research methods with the study of library research, field data and simulations. The approach used in this study is the empirical juridical approach. Elaboration upon the results is discussed further in this article.

Profil Penyakit Malaria Di Rumah Sakit Islam Siti Rahmah Padang Tahun 2018

2020 ◽  
Vol 2 (2) ◽  
pp. 08-15
Author(s):  
Rahma Triyana ◽  
Salmi Salmi
Keyword(s):  
Observational Study ◽  
Frequency Distribution ◽  
Cross Section ◽  
Laboratory Tests ◽  
Age Group ◽  
Normal Range ◽  
Cross Sectional ◽  
West Sumatra ◽  
Severity Of The Disease

Malaria is one of the health problems in Indonesia, especially West Sumatra. Determination of the description of Malaria disease in an area is needed to determine the spread and severity of the disease. This study aims to determine the frequency distribution according to age, sex and place of residence, description of the types of Plasmodium causes of Malaria and hematological features in Malaria patients at Siti Rahmah Padang Hospital in 2018. This type of research is a descriptive observational study with an approach or design cross section (cross sectional). The frequency distribution of Malaria sufferers in Siti Rahmah Padang Hospital in 2018 according to the highest age was in the age group 21-30 years as many as 28 cases (36.8%), the highest sex among men was 46 (60.5%) and the highest number of residences was found in Koto Tangah sub-district there were 31 cases (40.8%). The type of Plasmodium found in Malaria cases in Siti Rahmah Padang Hospital in 2018 was P. vivax (73 cases (96.05%)) and P. falciparum (3 cases (3.95%)). The results of laboratory tests on Hb, hematocrit, platelet and leukocyte levels in Malaria positive patients in Siti Rahmah Padang Hospital in 2018 were in the normal range.

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