scholarly journals Geologi og Vandboring. 2.udgave

1970 ◽  
Vol 31 ◽  
pp. 1-107
Author(s):  
Theodor Sorgenfrei ◽  
Ole Berthelsen
Keyword(s):  
Hydrostatic Pressure ◽  
Cross Sections ◽  
Salt Water ◽  
Point Of View ◽  
Glacial Deposits ◽  
Rock Composition ◽  
Gravel Beds ◽  
Rock Types ◽  
Groundwater Supply ◽  
Physical Geology

This book is intended as a simple geologic hand-book for well drillers and water supply engineers working in Denmark.The principles of physical geology are briefly treated in chapter I as an introduction to the geology of waterbearing beds in the subsoil of Denmark. The normal hydrologic cycle at the surface of the earth has been emphasized, illustrating the action of water upon landscape and subsurface. Glacial erosion and sedimentation are discussed rather comprehensively in order to make the user of the book familiar with the variability of the Quaternary deposits of the country. The work of the sea has also been treated, and the modes of marine erosion and sedimentation are outlined. The comparison of fluviatile, marine, and glacial deposits should draw attention to significant features and differences in rock composition and texture, and thus enable the well driller or engineer to determine the common rock types met with in water well drilling in this country. Weathering, disintegration, and crustal processes are only touched upon.In chapter II, which deals with the historical geology, the glacial drift that veils the bedrock formation over great parts of the country is described first, since a non-geologist should understand the nature of the Pleistocene glacial deposits before he is confronted with the less accessible formations of the subsurface. Regarding the pre-Pleistocene formation the description has been divided into two sections, the first one treating the areas W of Øresund, and the second one dealing with the island of Bornholm. The formations are described in their stratigraphic order of succession, and the sequence of sediments is described in rather great detail, with emphasis on the formations that provide aquifers of practical importance.Chapter III deals with the selection of drilling sites in general on the basis of geologic and hydrologic viewpoints, while chapter IV is a case history of the search for new groundwater supply areas for the waterworks of the township of Randers in Jutland. It includes an outline of existing major pumping stations in the town area and its surroundings, and a discussion of the geologic and hydrologic setting of the region. The plans for the test wells, which were proposed on the basis of geo-hydrologic considerations, are presented and compared with the results obtained through subsequent drilling.Waterbearing gravels and sands in the Pleistocene and waterbearing Upper Cretaceous limestone were tested. It appeared that rather complicated hydrologic situations are found in the surveyed area. One of the most cumbersome problems from a technical point of view is the occurrence of salt water in the aquifers. The salt water is assumed to be derived from deep-lying pre-Cretaceous formations from which it may ascend into the freshwater zones through structural dislocations due to a deficit in hydrostatic pressure in the more shallow aquifers. A natural drainage of the Gudenaa valley through highly permeable gravel beds near the surface may be responsible for the lower hydrostatic pressure in these aquifers. The last part of the book consists of a compilation of significant well logs, a list of geologic terms, stratigraphic tables, a geologic map of the pre-Pleistocene surface, and two cross sections through important wells.

scholarly journals Rock Emissivity Measurement for Infrared Thermography Engineering Geological Applications

2021 ◽  
Vol 11 (9) ◽  
pp. 3773
Author(s):  
Simone Mineo ◽  
Giovanna Pappalardo
Keyword(s):  
Surface Temperature ◽  
Infrared Thermography ◽  
High Sensitivity ◽  
Point Of View ◽  
Rock Surface ◽  
Rock Types ◽  
Ornamental Stones ◽  
Emissivity Measurement ◽  
Laboratory Tool ◽  
Non Destructive

Infrared thermography is a growing technology in the engineering geological field both for the remote survey of rock masses and as a laboratory tool for the non-destructive characterization of intact rock. In this latter case, its utility can be found either from a qualitative point of view, highlighting thermal contrasts on the rock surface, or from a quantitative point of view, involving the study of the surface temperature variations. Since the surface temperature of an object is proportional to its emissivity, the knowledge of this last value is crucial for the correct calibration of the instrument and for the achievement of reliable thermal outcomes. Although rock emissivity can be measured according to specific procedures, there is not always the time or possibility to carry out such measurements. Therefore, referring to reliable literature values is useful. In this frame, this paper aims at providing reference emissivity values belonging to 15 rock types among sedimentary, igneous and metamorphic categories, which underwent laboratory emissivity estimation by employing a high-sensitivity thermal camera. The results show that rocks can be defined as “emitters”, with emissivity generally ranging from 0.89 to 0.99. Such variability arises from both their intrinsic properties, such as the presence of pores and the different thermal behavior of minerals, and the surface conditions, such as polishing treatments for ornamental stones. The resulting emissivity values are reported and commented on herein for each different studied lithology, thus providing not only a reference dataset for practical use, but also laying the foundation for further scientific studies, also aimed at widening the rock aspects to investigate through IRT.

scholarly journals GRIBOV PROBLEM FOR GAUGE THEORIES: A PEDAGOGICAL INTRODUCTION

2004 ◽  
Vol 01 (04) ◽  
pp. 423-441 ◽  
Author(s):  
GIAMPIERO ESPOSITO ◽  
DIEGO N. PELLICCIA ◽  
FRANCESCO ZACCARIA
Keyword(s):  
Cross Sections ◽  
Gauge Theories ◽  
Functional Integral ◽  
Point Of View ◽  
Spherically Symmetric ◽  
Abelian Gauge ◽  
Gauge Transformations ◽  
Recent Developments ◽  
Gribov Ambiguity ◽  
Gribov Copies

The functional-integral quantization of non-Abelian gauge theories is affected by the Gribov problem at non-perturbative level: the requirement of preserving the supplementary conditions under gauge transformations leads to a nonlinear differential equation, and the various solutions of such a nonlinear equation represent different gauge configurations known as Gribov copies. Their occurrence (lack of global cross-sections from the point of view of differential geometry) is called Gribov ambiguity, and is here presented within the framework of a global approach to quantum field theory. We first give a simple (standard) example for the SU(2) group and spherically symmetric potentials, then we discuss this phenomenon in general relativity, and recent developments, including lattice calculations.

Sea Water Intrusion Monitoring on the Sendangbiru of the Southern Malang Coastal Area based on Geoelectrical Resistivity Data

2021 ◽  
Vol 14 (9) ◽  
pp. 43-48
Author(s):  
Sunaryo .
Keyword(s):  
Data Acquisition ◽  
Cross Section ◽  
Seawater Intrusion ◽  
Cross Sections ◽  
Sea Water ◽  
Salt Water ◽  
Sea Water Intrusion ◽  
Electrical Sounding ◽  
Geoelectrical Resistivity ◽  
Intrusion Layer

The study was conducted with the objective to distinguish the presence of seawater intrusion layer or salt-water aquifer distribution along the data acquisition line at the locations. Data acquisition was conducted by using the Wenner-Schumberger configuration of geoelectrical resistivity. From this research, 4 lines and 4 points of vertical electrical sounding (VES) data for every line were obtained with the distance between electrode a as 10m. Based on the data processing, obtained depth up to 120m with the smallest resistivity value is 0.02Ωm and the largest is 6764.52Ωm. To make the distribution of resistivity values along the path line of the study, cross sections were made until a depth of 120m. Based on the cross-section, the low resistivity value (less than 1.5 Ωm) that interpreted as a seawater intrusion layer or salt water aquifer distribution is located at varying depths. There are intrusions for the SB1 cross section, there is an intrusion at a depth of 6m-7m as far as 10m, at a depth of 6m-8m as far as 10m for the SB2 cross section and at a depth of 22m - 26m as far as 25m for the SB3 cross section.

Influence of Surface Condition on Oxides Layer Morphology on NiCrAlY Coating during Oxidation at Temperature 1000°C and 1100°C

2015 ◽  
Vol 227 ◽  
pp. 385-388 ◽  
Author(s):  
Grzegorz Moskal ◽  
Dawid Niemiec
Keyword(s):  
Cross Sections ◽  
Surface Characterization ◽  
Surface Condition ◽  
Point Of View ◽  
Inconel 625 ◽  
Oxidation Test ◽  
Nicraly Coating ◽  
Static Oxidation ◽  
Plasma Spraying Process

Characterization of top-surface of NiCrAlY coating deposited by plasma spraying process on Inconel 625 Ni based superalloys was analyzed in two different completely conditions. First of them was as sprayed state of NiCrAlY coating and the second one was condition after grinding process. The basic aim of this treatment was related to obtain totally different conditions of coatings surface especially from roughness point of view. Those two types of top surface morphology was a base to comparison of oxidation resistant during static oxidation test at temperature of 1000°C and 1100°C. The temperature of static oxidation test was 1000°C and 1100°C. The specimens were moved out from furnace after 25, 300, 500, 750 and 1000 hours of exposition in laboratory air. The range of investigations after each interval included top surface characterization of specimens by SEM, XRD and EDS method. Those investigations showed that different types of top surface conditions had a fundamental influence on oxides layer morphology. Especially in the case of phase`s constituent of oxides zone. More detailed investigations were made on the cross sections of two types of investigated specimens. Analysis of oxides layer morphology showed in this case basic differences in thickness of oxides zone which was much higher in the case of as sprayed NiCrAlY coating.

scholarly journals Electron-capture modes with realistic nuclear structure calculations

2019 ◽  
Vol 21 ◽  
pp. 4
Author(s):  
P. G. Giannaka ◽  
T. S. Kosmas
Keyword(s):  
Electron Capture ◽  
Cross Sections ◽  
Nuclear Reactions ◽  
Random Phase ◽  
Point Of View ◽  
Electron Neutrino ◽  
Β Decay ◽  
Decay Modes ◽  
Theory Point ◽  
Nuclear Structure Calculations

Nuclear electron capture posses prominent position among other weak interaction processes occuring in explosive nucleosynthesis. In particular, this process plays important role in the core-colapse of massive stars by modifying the electron to baryon ratio Ye. From a nuclear theory point of view, such processes may be studied by using the same nuclear methods (e.g. the quasi-particle random phase approximation, QRPA), employed in the present work with these used for the one-body charge changing nuclear reactions (β-decay modes, charged-current electron-neutrino absorption by nuclei, etc). In this work we calculate e−-capture cross sections on 56Fe using two different approaches. At first, original cross section calculations are perfored by using the pn-QRPA method considering all the accessible transitions of the final nucleus 56Mn. Secondly, we evaluate the Gamow-Teller strength distributions and obtain the cross sections at the limit of zero-momentum transfer. The agreement between the two methods is very good.

QEMSCAN-Assisted Interpretation of Imbibition Capillary Pressure for Multiporosity Carbonate Rocks

SPE Journal ◽  
2020 ◽  
pp. 1-17
Author(s):  
Aymen Alramadhan ◽  
Yildiray Cinar
Keyword(s):  
Capillary Pressure ◽  
Numerical Models ◽  
Rock Composition ◽  
Rock Samples ◽  
Rock Types ◽  
Centrifuge Tests ◽  
Medium Permeability ◽  
Mercury Injection Capillary Pressure ◽  
The Impact ◽  
Selection Of

Summary In this paper, we present an experimental study that explores the potential links between the imbibition capillary pressure Pci and the pore systems and/or mineralogy for carbonate reservoirs undergoing waterflood. A systematic workflow has been formulated to ensure the data quality ofPci, minimize uncertainty in derivingPci from centrifuge tests, and analyze the data considering the pore-size distribution from mercury injection capillary pressure (MICP) and mineralogy from Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN). The workflow starts with assessing the centrifuge production data for gravity-capillary equilibrium at each speed. Then, the quality-checked data are used to generate six differentPci curves using analytical and numerical models. The resulting curves provide a measure of the variability in solutions for various rock types and assist in the selection of the most-representativePci curve. Finally, the representative Pci curves of all rock samples are analyzed together with the MICP and QEMSCAN data to examine the change in Pci curves as a result of changes in the number and character of rock types, pore systems, dominant pore-throat radii, and mineralogy. Findings from this study shed light on the impact of mineralogy and pore systems on Pci. From the mineralogy perspective, the presence of dolomite, microporous calcite, or rutile and anatase (TiO2) within the rock composition is found to affect the Pci of the carbonate samples used in this study. The rock samples with these minerals should be separated from other bimodal samples before attempting to obtain a correlation between Pci and pore systems. The data analysis further reveals that some bimodal samples of medium permeability yield a better waterflood imbibition efficiency than those of the high-permeability samples. This observation is attributed to a better communication between the micropore and macropore systems, and a closer proximity of the peak radii of the micro- and macropore systems of the medium-permeability samples.

scholarly journals Influence of measuring force on CMM accuracy

2018 ◽  
Vol 208 ◽  
pp. 03004
Author(s):  
Bin Wang
Keyword(s):  
Cross Sections ◽  
Measurement Accuracy ◽  
Coordinate Measuring Machine ◽  
Point Of View ◽  
Signal Acquisition ◽  
Force Model ◽  
Thin Part ◽  
Measuring Machine ◽  
The Relationship ◽  
Measuring Force

The measuring accuracy of CMM (Coordinate Measuring Machine) is influenced by many factors, such as temperature, humidity, measuring force and method of signal acquisition. For thin parts, the influence of measuring force is especially obvious. In this paper, the relationship between measuring force and measurement accuracy is studied for a thin part with a U-shaped cross-section. By analyzing the structure of the probe and establishing the force model, the influencing factors of the accuracy of CMM are obtained, and the influence of the contact deformation and the bending deformation on the measurement accuracy is analyzed from the point of view of material mechanics. At the same time, the measurement accuracy of different measuring cross-sections is analyzed. Through the research of this paper, the relationship between measuring force and CMM is established, and an effective method to improve the accuracy of CMM is also found.

Collapse study of thin-walled polygonal section columns subjected to oblique loads

2007 ◽  
Vol 221 (7) ◽  
pp. 801-810 ◽  
Author(s):  
P Hosseini-Tehrani ◽  
S Pirmohammad
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Rigid Wall ◽  
Point Of View ◽  
Explicit Finite Element ◽  
Thin Walled ◽  
Oblique Load ◽  
Crash Behaviour ◽  
Vehicle Crashworthiness ◽  
Load Conditions

The present paper deals with the collapse simulation of aluminium alloy extruded polygonal section columns subjected to oblique loads. Oblique load conditions in numerical simulations are applied by means of impacting a declined rigid wall on the tubes with no friction in this task. The explicit finite element code LS-DYNA is used to simulate the crash behaviour of polygonal section columns that are undergoing both axial and bending collapse situations. In order to validate LS-DYNA results the collapse procedure of square columns is successfully simulated and the obtained numerical results are compared with actual available experimental data. Mean crush loads and permanent displacements corresponding to load angles have been investigated, considering columns with square, hexagonal, octagonal, decagonal, and circular cross-sections. It is shown that the octagonal cross-section has better characteristics from the point of view of vehicle crashworthiness under oblique load conditions.

JOSEPH HENRY AND GEOLOGY AT PRINCETON

2019 ◽  
Vol 38 (2) ◽  
pp. 232-275
Author(s):  
DAVIS A. YOUNG
Keyword(s):  
New Jersey ◽  
Cross Sections ◽  
Natural Philosophy ◽  
Internal Heat ◽  
The United States ◽  
Structural Features ◽  
Princeton University ◽  
Rock Types ◽  
College Of New Jersey ◽  
The Impact

ABSTRACT The first documented geology lectures at Princeton were given in 1825 by John Finch (circa 1790–circa 1835), an English visitor to the United States. In the 1830s, John Torrey (1796–1873) delivered a few geology and mineralogy lectures at the College of New Jersey (now Princeton University), but Joseph Henry (1797–1878), Professor of Natural Philosophy at the College of New Jersey from 1832 to 1848, introduced the first repeated geology course. In the 1830s, the College of New Jersey instituted a handful of short courses on topics outside of the regular curriculum. Geology was assigned to Henry, owing to his geological experience with Amos Eaton (1776–1842) along the recently opened Erie Canal. Henry taught geology for the first time in August 1841, repeated the course in 1843, 1846, and 1847, and probably also in 1844, 1845, 1850, and 1851. Henry typically focused on geophysical aspects of Earth, such as internal heat and Laplace's nebular hypothesis. He also discussed the geologic time scale from Primitive to Alluvium and Diluvium with descriptions of rock types and fossil content of each group. The final lecture was normally devoted to paleontology. Henry relied on Eaton and Edward Hitchcock (1793–1864) for much of his information and took advantage of published cross-sections to explain structural features. The content and timing of the various offerings is reconstructed from Henry's various lecture notes, dated correspondence, and three student notebooks. The impact of Henry's course on students, himself, and the Smithsonian Institution is evaluated.

Studies on Design Optimization of Coronary Stents

2008 ◽  
Vol 2 (1) ◽  
Author(s):  
K. Srinivas ◽  
T. Nakayama ◽  
M. Ohta ◽  
S. Obayashi ◽  
T. Yamaguchi
Keyword(s):  
Design Optimization ◽  
Cross Sections ◽  
Latin Hypercube Sampling ◽  
Coronary Stents ◽  
Point Of View ◽  
Two Dimensional ◽  
Reattachment Length ◽  
Design Variables ◽  
Two Dimensional Flow ◽  
The Relationship

The stent design itself seems to be one of the factors responsible for restenosis. As a remedy, the present work attempts to perform a design optimization of coronary stents from a hemodynamic point of view. For the purpose, we have applied the principles of modern exploration of design space restricting ourselves to two-dimensional considerations. Width, thickness, and spacing of the struts of the stent formed the design variables. The objectives chosen for optimization were the vorticity generated, length of recirculation zone, and the reattachment distance in between the struts. Both semicircular and rectangular cross sections of stents were included. Starting with the range of design variables, sample stent cases were generated using Latin hypercube sampling. Objective functions were calculated for each of these by computing the two-dimensional flow using software FLUENT under the assumption of a steady, Newtonian flow considering a model stent with three struts. This was followed by Kriging to construct a response surface, which gives the relationship between the objectives and the design variables. The procedure gave nondominated fronts, which consist of optimized designs. Stents with minimum vorticity, with minimum recirculation distance, and the ones with maximum reattachment length in between struts were generated. The procedure is capable of producing the optimum set of design variables to achieve the prescribed objectives.

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