Matches in SemOpenAlex for { <https://semopenalex.org/work/W2002956546> ?p ?o ?g. }
Showing items 1 to 98 of
98
with 100 items per page.
- W2002956546 endingPage "1126" @default.
- W2002956546 startingPage "1106" @default.
- W2002956546 abstract "An important element of electromagnetic (EM) prospecting is survey design; numerical modeling algorithms may be used to calculate signal‐to‐geologic‐noise (S/N) ratios to compare different survey configurations and measured responses quantitatively. Our models consist of a prismatic three‐dimensional (3-D) target in a conductive half‐space which may contain an overburden conductor; the models are energized by a time‐varying current transmitted in a loop of wire. The signal is the scattered or anomalous response of the target, while the geologic noise is either the response of the half‐space or the anomalous response of the overburden conductor. For typical loop sizes in exploration, the coincident‐loop configuration has a relatively high S/N ratio and thus a relatively high capability to resolve the target in the case of half‐space noise. Measurements made with the horizontal‐loop, moving‐coil configuration can be just as effective if the coil separation is one and one‐half to two times the depth of burial of the target and the transmitting and receiving coils are on opposite sides of the target. For coil positions on one side of the target, the S/N ratio decreases with increasing separation. The advantage in resolving power provided by the coincident loop’s superior S/N ratio diminishes as the size of the loop increases. For the case of noise due to the overburden conductor, the horizontal‐loop configuration with a large coil separation is optimal. If the depth of the target is unknown, the fixed‐loop, roving‐receiver configuration is useful for detecting the target but poor in resolving its depth because its S/N ratio is the least sensitive to the depth. With the fixed‐loop configuration, galvanic effects enhance the detectability of the target in a conductive half‐space, but inhibit detection if an overburden conductor is present. Regarding the S/N ratio, there does not appear to be any advantage in measuring the step response of a 3-D target in a conductive environment versus measuring the impulse response. The shapes of their respective S/N anomalies are essentially the same and the maximum impulse S/N ratio is 10 to 30 percent larger than the maximum step S/N ratio, though it occurs later in time by a factor of about 1.7. Although transient S/N ratios for a 3-D target in a conductive host reach a maximum value and then decrease with increasing time, harmonic S/N ratios do not necessarily reach a maximum value at an intermediate frequency. For all three survey configurations and both types of noise, target depths, and half‐space conductivities studied here, maximum transient S/N ratios are larger than harmonic S/N ratios. Peak step S/N ratios are 30 to 50 percent larger than corresponding in‐phase ratios in the case of half‐space noise, and several times larger in the case of the overburden conductor. A phase rotation of the target’s response due to the conductive host appears to amplify the quadrature S/N ratio relative to the in‐phase S/N ratio. However, in‐phase S/N ratios are always much larger than quadrature S/N ratios over the range of host resistivities used in this study." @default.
- W2002956546 created "2016-06-24" @default.
- W2002956546 creator A5030857471 @default.
- W2002956546 creator A5068082972 @default.
- W2002956546 date "1987-08-01" @default.
- W2002956546 modified "2023-09-27" @default.
- W2002956546 title "An evaluation of electromagnetic methods in the presence of geologic noise" @default.
- W2002956546 cites W1965238973 @default.
- W2002956546 cites W2022732336 @default.
- W2002956546 cites W2035155528 @default.
- W2002956546 cites W2043296273 @default.
- W2002956546 cites W2047543484 @default.
- W2002956546 cites W2053967400 @default.
- W2002956546 cites W2065815220 @default.
- W2002956546 cites W2065987502 @default.
- W2002956546 cites W2076128990 @default.
- W2002956546 cites W2077720156 @default.
- W2002956546 cites W2081471374 @default.
- W2002956546 cites W2091478082 @default.
- W2002956546 cites W2121660468 @default.
- W2002956546 cites W2128899785 @default.
- W2002956546 cites W2150158160 @default.
- W2002956546 cites W2159760055 @default.
- W2002956546 cites W2162984000 @default.
- W2002956546 doi "https://doi.org/10.1190/1.1442376" @default.
- W2002956546 hasPublicationYear "1987" @default.
- W2002956546 type Work @default.
- W2002956546 sameAs 2002956546 @default.
- W2002956546 citedByCount "31" @default.
- W2002956546 countsByYear W20029565462015 @default.
- W2002956546 countsByYear W20029565462016 @default.
- W2002956546 countsByYear W20029565462021 @default.
- W2002956546 crossrefType "journal-article" @default.
- W2002956546 hasAuthorship W2002956546A5030857471 @default.
- W2002956546 hasAuthorship W2002956546A5068082972 @default.
- W2002956546 hasConcept C114614502 @default.
- W2002956546 hasConcept C115961682 @default.
- W2002956546 hasConcept C120665830 @default.
- W2002956546 hasConcept C121332964 @default.
- W2002956546 hasConcept C127313418 @default.
- W2002956546 hasConcept C154945302 @default.
- W2002956546 hasConcept C163258240 @default.
- W2002956546 hasConcept C184670325 @default.
- W2002956546 hasConcept C187320778 @default.
- W2002956546 hasConcept C199360897 @default.
- W2002956546 hasConcept C202374169 @default.
- W2002956546 hasConcept C24890656 @default.
- W2002956546 hasConcept C2524010 @default.
- W2002956546 hasConcept C2777201227 @default.
- W2002956546 hasConcept C2779843651 @default.
- W2002956546 hasConcept C30403606 @default.
- W2002956546 hasConcept C33923547 @default.
- W2002956546 hasConcept C34800285 @default.
- W2002956546 hasConcept C41008148 @default.
- W2002956546 hasConcept C62520636 @default.
- W2002956546 hasConcept C99498987 @default.
- W2002956546 hasConceptScore W2002956546C114614502 @default.
- W2002956546 hasConceptScore W2002956546C115961682 @default.
- W2002956546 hasConceptScore W2002956546C120665830 @default.
- W2002956546 hasConceptScore W2002956546C121332964 @default.
- W2002956546 hasConceptScore W2002956546C127313418 @default.
- W2002956546 hasConceptScore W2002956546C154945302 @default.
- W2002956546 hasConceptScore W2002956546C163258240 @default.
- W2002956546 hasConceptScore W2002956546C184670325 @default.
- W2002956546 hasConceptScore W2002956546C187320778 @default.
- W2002956546 hasConceptScore W2002956546C199360897 @default.
- W2002956546 hasConceptScore W2002956546C202374169 @default.
- W2002956546 hasConceptScore W2002956546C24890656 @default.
- W2002956546 hasConceptScore W2002956546C2524010 @default.
- W2002956546 hasConceptScore W2002956546C2777201227 @default.
- W2002956546 hasConceptScore W2002956546C2779843651 @default.
- W2002956546 hasConceptScore W2002956546C30403606 @default.
- W2002956546 hasConceptScore W2002956546C33923547 @default.
- W2002956546 hasConceptScore W2002956546C34800285 @default.
- W2002956546 hasConceptScore W2002956546C41008148 @default.
- W2002956546 hasConceptScore W2002956546C62520636 @default.
- W2002956546 hasConceptScore W2002956546C99498987 @default.
- W2002956546 hasIssue "8" @default.
- W2002956546 hasLocation W20029565461 @default.
- W2002956546 hasOpenAccess W2002956546 @default.
- W2002956546 hasPrimaryLocation W20029565461 @default.
- W2002956546 hasRelatedWork W1538596762 @default.
- W2002956546 hasRelatedWork W2018776701 @default.
- W2002956546 hasRelatedWork W2061252580 @default.
- W2002956546 hasRelatedWork W2113972673 @default.
- W2002956546 hasRelatedWork W2125937206 @default.
- W2002956546 hasRelatedWork W2130220682 @default.
- W2002956546 hasRelatedWork W2150667673 @default.
- W2002956546 hasRelatedWork W2510258589 @default.
- W2002956546 hasRelatedWork W2897736835 @default.
- W2002956546 hasRelatedWork W2990935682 @default.
- W2002956546 hasVolume "52" @default.
- W2002956546 isParatext "false" @default.
- W2002956546 isRetracted "false" @default.
- W2002956546 magId "2002956546" @default.
- W2002956546 workType "article" @default.