SOME RESULTS OF GEOPHYSICAL PROSPECTING CONDUCTED FOR THE GEOLOGICAL SURVEY OF INDIA FROM 1945–1948

Geophysics ◽  
1950 ◽  
Vol 15 (4) ◽  
pp. 704-731
Author(s):  
G. Dessau
Keyword(s):  
Electrical Resistivity ◽  
Spontaneous Polarization ◽  
Geological Survey ◽  
Foundation Engineering ◽  
Geophysical Prospecting ◽  
Geophysical Surveys ◽  
Engineering Problems ◽  
Geophysical Investigations ◽  
The Many ◽  
Geological Background

The methods used and some results obtained from geophysical investigations conducted by the Geophysical Section of the Geological Survey of India from 1945–1948 are presented. The many difficulties encountered in obtaining the proper instruments necessitated the widespread use of equipment made by the Section. This is one of the reasons why electrical resistivity and spontaneous polarization methods were employed in preference to others. The majority of the geophysical surveys during this three year period were concentrated in the search for minerals, water supplies, and in the solution of foundation engineering problems. The emphasis on these phases of geophysical prospecting rather than on oil surveys was necessary because, of the types of equipment available, as well as the priority assigned to these projects. Two spontaneous polarization, two magnetic, and two resistivity surveys are described, in addition to one carried out jointly by electrical and seismic methods. The geological background of these investigations are also briefly mentioned together with some details of the equipment used.

Airborne geophysical surveys in Greenland in 1998

1999 ◽  
pp. 34-38 ◽  
Author(s):  
Thorkild M. Rasmussen ◽  
Leif Thorning
Keyword(s):  
High Resolution ◽  
Geophysical Data ◽  
Digital Data ◽  
Geological Survey ◽  
Magnetic Data ◽  
Magnetic Survey ◽  
Original Series ◽  
Geophysical Surveys ◽  
The Government

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Rasmussen, T. M., & Thorning, L. (1999). Airborne geophysical surveys in Greenland in 1998. Geology of Greenland Survey Bulletin, 183, 34-38. https://doi.org/10.34194/ggub.v183.5202 _______________ Airborne geophysical surveying in Greenland during 1998 consisted of a magnetic project referred to as ‘Aeromag 1998’ and a combined electromagnetic and magnetic project referred to as ‘AEM Greenland 1998’. The Government of Greenland financed both with administration managed by the Geological Survey of Denmark and Greenland (GEUS). With the completion of the two projects, approximately 305 000 line km of regional high-resolution magnetic data and approximately 75 000 line km of detailed multiparameter data (electromagnetic, magnetic and partly radiometric) are now available from government financed projects. Figure 1 shows the location of the surveyed areas with highresolution geophysical data together with the area selected for a magnetic survey in 1999. Completion of the two projects was marked by the release of data on 1 March, 1999. The data are included in the geoscientific databases at the Survey for public use; digital data and maps may be purchased from the Survey.

Model-Eliciting Activities: A Research-Based Method for Inquiry Learning and Professional Development in the Engineering Classroom

2008 ◽  
Author(s):  
Tamara J. Moore
Keyword(s):  
Complex Systems ◽  
Student Development ◽  
Engineering Problem ◽  
First Year ◽  
Foundation Engineering ◽  
Underrepresented Populations ◽  
Model Eliciting Activities ◽  
Engineering Problems ◽  
The Given ◽  
Mathematics And Science

Attracting students to engineering is a challenge. In addition, ABET requires that engineering graduates be able to work on multi-disciplinary teams and apply mathematics and science when solving engineering problems. One manner of integrating teamwork and engineering contexts in a first-year foundation engineering course is through the use of Model-Eliciting Activities (MEAs) — realistic, client-driven problems based on the models and modeling theoretical framework. A Model-Eliciting Activity (MEA) is a real-world client-driven problem. The solution of an MEA requires the use of one or more mathematical or engineering concepts that are unspecified by the problem — students must make new sense of their existing knowledge and understandings to formulate a generalizable mathematical model that can be used by the client to solve the given and similar problems. An MEA creates an environment in which skills beyond mathematical abilities are valued because the focus is not on the use of prescribed equations and algorithms but on the use of a broader spectrum of skills required for effective engineering problem-solving. Carefully constructed MEAs can begin to prepare students to communicate and work effectively in teams; to adopt and adapt conceptual tools; to construct, describe, and explain complex systems; and to cope with complex systems. MEAs provide a learning environment that is tailored to a more diverse population than typical engineering course experiences as they allow students with different backgrounds and values to emerge as talented, and that adapting these types of activities to engineering courses has the potential to go beyond “filling the gaps” to “opening doors” to women and underrepresented populations in engineering. Further, MEAs provide evidence of student development in regards to ABET standards. Through NSF-funded grants, multiple MEAs have been developed and implemented with a MSE-flavored nanotechnology theme. This paper will focus on the content, implementation, and student results of one of these MEAs.

Investigating the Effective Resistivity of Reinforced Concrete Waste Storage Tanks at the Hanford Site

Geophysics ◽  
2021 ◽  
pp. 1-50
Author(s):  
Allan Haas ◽  
Dale F. Rucker ◽  
Marc T. Levitt
Keyword(s):  
Electrical Resistivity ◽  
Reinforced Concrete ◽  
Geophysical Methods ◽  
Underground Storage ◽  
Storage Tanks ◽  
Hanford Site ◽  
Underground Storage Tanks ◽  
Effective Resistivity ◽  
Geophysical Surveys ◽  
Wide Range

Industrialized sites pose challenges for conducting electrical resistivity geophysical surveys, as the sites typically contain metallic infrastructure that can mask electrolytic-based soil and groundwater contamination. The Hanford site in eastern Washington State, USA, is an industrialized site with underground storage tanks, piping networks, steel fencing, and other potentially interfering infrastructure that could inhibit the effectiveness of electrical resistivity tomography (ERT) to map historical and monitor current waste releases. The underground storage tanks are the largest contributor by volume to subsurface infrastructure and can be classified as reinforced concrete structures with an internal steel liner. Directly measuring the effective value for the electrical resistivity of the tank, i.e., the combination of individual components that comprise the tank’s shell, is not reasonably possible because they are buried and dangerously radioactive. Therefore, we indirectly assess the general resistivity of the tanks and surrounding infrastructure by developing synthetic ERT models with a parametric forward modeling study using a wide range of resistivity values from 1×10−6 to 1×104 ohm-m, which are equivalent to steel and dry rock, respectively. The synthetic models used the long-electrode ERT method (LE-ERT), whereby steel cased metallic wells surrounding the tanks are used as electrodes. The patterns and values of the synthetic tomographic models were then compared to LE-ERT field data from the AX tank farm at the Hanford site. This indirect method of assessing the effective resistivity revealed that the reinforced concrete tanks are electrically resistive and the accompanying piping infrastructure has little influence on the overall resistivity distribution when using electrically based geophysical methods for characterizing or monitoring waste releases. Our findings are consistent with nondestructive testing literature that also shows reinforced concrete to be generally resistive.

scholarly journals Data for the potential gold mineralization mapping with the applications of Electrical Resistivity Imaging and Induced Polarization geophysical surveys

Data in Brief ◽  
2019 ◽  
Vol 22 ◽  
pp. 830-835 ◽  
Author(s):  
Mohd Hariri Arifin ◽  
John Stephen Kayode ◽  
Muhammad Khairel Izwan ◽  
Hussein Ahmed Hasan Zaid ◽  
Hamzah Hussin
Keyword(s):  
Electrical Resistivity ◽  
Gold Mineralization ◽  
Induced Polarization ◽  
Electrical Resistivity Imaging ◽  
Resistivity Imaging ◽  
Geophysical Surveys

GEOPHYSICAL METHODS ADAPTED TO HIGHWAY ENGINEERING PROBLEMS

Geophysics ◽  
1952 ◽  
Vol 17 (3) ◽  
pp. 505-530 ◽  
Author(s):  
R. Woodward Moore
Keyword(s):  
Seismic Refraction ◽  
Geophysical Methods ◽  
Engineering Structures ◽  
Highway Engineering ◽  
Earth Resistivity ◽  
The Earth ◽  
Ore Bodies ◽  
Geophysical Surveys ◽  
Engineering Problems ◽  
Test Use

Of the several geophysical methods used in exploration for oil and useful ore bodies, the earth‐resistivity and seismic‐refraction tests have been found to be the most adaptable to the shallow tests generally required in highway construction work. Of these, the earth‐resistivity test is the faster and has a wider range of application to highway problems than does the seismic test. Use of both methods of tests in subsurface explorations for engineering structures is expanding. The paper cites a growing need for a more thorough subsurface investigation of all engineering structure sites and gives examples of field data obtained by the Bureau of Public Roads when making preliminary geophysical surveys of proposed highway locations or structure sites. The economic aspects and the advantages and limitations of the two methods of test are discussed with particular reference to their application to highway engineering problems.

scholarly journals Large-scale electrical resistivity tomography in the Cheb Basin (Eger Rift) at an International Continental Drilling Program (ICDP) monitoring site to image fluid-related structures

Solid Earth ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 1951-1969 ◽  
Author(s):  
Tobias Nickschick ◽  
Christina Flechsig ◽  
Jan Mrlina ◽  
Frank Oppermann ◽  
Felix Löbig ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Fault Zone ◽  
Large Scale ◽  
Monitoring Site ◽  
Earthquake Activity ◽  
Resistivity Tomography ◽  
Scientific Drilling ◽  
Eger Rift ◽  
Geophysical Surveys ◽  
Cheb Basin

Abstract. The Cheb Basin, a region of ongoing swarm earthquake activity in the western Czech Republic, is characterized by intense carbon dioxide degassing along two known fault zones – the N–S-striking Počatky–Plesná fault zone (PPZ) and the NW–SE-striking Mariánské Lázně fault zone (MLF). The fluid pathways for the ascending CO2 of mantle origin are one of the subjects of the International Continental Scientific Drilling Program (ICDP) project “Drilling the Eger Rift” in which several geophysical surveys are currently being carried out in this area to image the topmost hundreds of meters to assess the structural situation, as existing boreholes are not sufficiently deep to characterize it. As electrical resistivity is a sensitive parameter to the presence of conductive rock fractions as liquid fluids, clay minerals, and also metallic components, a large-scale dipole–dipole experiment using a special type of electric resistivity tomography (ERT) was carried out in June 2017 in order to image fluid-relevant structures. We used permanently placed data loggers for voltage measurements in conjunction with moving high-power current sources to generate sufficiently strong signals that could be detected all along the 6.5 km long profile with 100 and 150 m dipole spacings. After extensive processing of time series for voltage and current using a selective stacking approach, the pseudo-section is inverted, which results in a resistivity model that allows for reliable interpretations depths of up than 1000 m. The subsurface resistivity image reveals the deposition and transition of the overlying Neogene Vildštejn and Cypris formations, but it also shows a very conductive basement of phyllites and granites that can be attributed to high salinity or rock alteration by these fluids in the tectonically stressed basement. Distinct, narrow pathways for CO2 ascent are not observed with this kind of setup, which hints at wide degassing structures over several kilometers within the crust instead. We also observed gravity and GPS data along this profile in order to constrain ERT results. A gravity anomaly of ca. −9 mGal marks the deepest part of the Cheb Basin where the ERT profile indicates a large accumulation of conductive rocks, indicating a very deep weathering or alteration of the phyllitic basement due to the ascent of magmatic fluids such as CO2. We propose a conceptual model in which certain lithologic layers act as caps for the ascending fluids based on stratigraphic records and our results from this experiment, providing a basis for future drillings in the area aimed at studying and monitoring fluids.

On rhodonite and tephroite from Treburland manganese mine, Altarnun, Cornwall; and on rhodonite from other localities in Cornwall and Devonshire

1946 ◽  
Vol 27 (194) ◽  
pp. 221-235 ◽  
Author(s):  
Arthur Russell
Keyword(s):  
Sedimentary Rocks ◽  
Point Of View ◽  
Contact Metamorphism ◽  
Geological Survey ◽  
The West ◽  
The Past ◽  
Manganese Deposits ◽  
The Many

Of the many small manganese deposits which have in the past been worked in both Cornwall and Devonshire that of Treburland is from the mineralogical point of view by far the most remarkable, its especial interest being due to the variety of minerals which it has afforded and to the fact that it and one other are the only manganese deposits in the west of England which are known to lie on the contact of igneous and sedimentary rocks and which have consequently been vitally affected by contact metamorphism.The following observations are based on frequent visits to the spot since the year 1906, when I first stumbled across the locality, which, strange to say, has only received very cursory mention by the Geological Survey and has altogether escaped mention in mineralogical literature.

To: NOMOGRAMS TO SPEED UP SEISMIC REFRACTION COMPUTATIONS, GEOPHYSICS, OCTOBER, 1960.

Geophysics ◽  
1961 ◽  
Vol 26 (1) ◽  
pp. 102-102
Author(s):  
Tsvi Meidav
Keyword(s):  
Electrical Resistivity ◽  
Ground Water ◽  
Seismic Refraction ◽  
Geological Survey ◽  
Field Techniques ◽  
Electrical Resistivity Survey ◽  
Resistivity Survey ◽  
Offset Distance ◽  
Speed Up

The last sentence in the paper “Nomograms . . . ,” p. 1045 should read: “Pass a line through i and Z and read off X, the offset distance.” Also, a regrettable typist omission is present in the paper “An Electrical Resistivity Survey for Ground Water,” and was not captured in reading the typed manuscript. The sentence before last on p. 1093 should read: “The project was later concluded under the auspices of the Missouri Geological Survey, with the active help of Dr. H. C. Spicer of the U.S.G.S. who spent much time in instructing the author in both field techniques and interpretation.”

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