The Experts below are selected from a list of 75 Experts worldwide ranked by ideXlab platform
Jason C Sanford - One of the best experts on this subject based on the ideXlab platform.
-
the cretaceous paleogene boundary Deposit in the gulf of mexico large Scale oceanic basin response to the chicxulub impact
Journal of Geophysical Research, 2016Co-Authors: Jason C Sanford, John W Snedden, Sean P S GulickAbstract:Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatan Peninsula, the gulf is the premier locale in which to study the near-field geologic effect of a bolide impact. We mapped a thick (decimeter- to hectometer-Scale) Deposit of carbonate debris at the Cretaceous-Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret Deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the Deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow-water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact Deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact-generated Deposition overwhelmed virtually all topography and Depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.
Bernard Tribollet - One of the best experts on this subject based on the ideXlab platform.
-
on the intrinsic coupling between constant phase element parameters α and q in electrochemical impedance spectroscopy
Electrochimica Acta, 2012Co-Authors: Pedro Cordobatorres, Bernard Tribollet, Thiago J Mesquita, O Devos, Virginie Roche, R P NogueiraAbstract:Abstract This paper presents experimental evidences of an intrinsic coupling between the α and Q parameters of constant phase elements (CPE) used in equivalent electrical circuits for EIS data fitting. Clear correlations have been found for two different experimental conditions, anodic dissolution and Scale Deposit, for which CPE behavior appears as the result of a time constant distribution originated from surface inhomogeneity. Results are in agreement with a coupling function that relates CPE parameters with interfacial quantities such as the ohmic and charge transfer resistances, and also with a characteristic interfacial capacitance whose meaning is addressed here. Although this relationship was initially derived from a theoretical model in which perfect CPE behavior was caused by a double-layer capacity distribution along the interface, it has been extensively used in the literature to estimate interface capacitance from CPE parameters in very different complex systems without any definitive evidence of it. However, its exportability to real systems can be explained from the fact that it can be deduced from simple and general arguments. In this paper we argue on these ideas in the basis of experimental evidences.
-
simultaneous eis and in situ microscope observation on a partially blocked electrode application to Scale electroDeposition
Electrochimica Acta, 2006Co-Authors: O Devos, C Gabrielli, Bernard TribolletAbstract:A novel technique allowed EIS and microscopical observation of the interface between electrode and solution to be coupled in situ. The electrochemical reduction of oxygen was investigated by using this device when the electrode surface was progressively covered by an insulating layer of Scale Deposit. It was shown that two time domains can be distinguished from the initial time of the experiment corresponding to a bare electrode up to a totally blocked surface. In the first part of the experiment, EIS showed one time constant which characterizes the charge transfer process of water reduction. When the percentage of coverage reached more than 80%, this latter electrochemical contribution to EIS was negligible and the reduction process of oxygen was highlighted by two time constants observed from impedance diagrams. The high frequency response characterized the charge transfer process and the low frequency loop identified the diffusion process of oxygen. An electrochemical model was proposed to explain the shape of the impedance spectra plotted with respect to the time of coverage. The good correlation between the experimental and the fitted model curves led to the change versus time of the different parameters of the equivalent circuit. It notably showed that the double layer capacity was directly proportional to the active surface measured by the microscope observation until the surface was totally covered, according to the expectations in the experimental conditions used here.
-
characterization of Deposits by direct observation and by electrochemical methods on a conductive transparent electrode application to biofilm and Scale Deposit under cathodic protection
International symposium on Electrochemical methods in Corrosion Research, 2001Co-Authors: H Cachet, El T Moustafid, D Herbertguillou, D Festy, S Touzain, Bernard TribolletAbstract:A new device is proposed where the electrode is a transparent electrode in modified SnO 2 . With this new electrode the reduction of oxygen occurs in a way similar to a gold electrode. Simultaneously the oxygen current is recorded versus time and picture of the interface itself is taken with a digital camera through the electrode. An image analysis is performed to determine the coated area and the number of objects by surface unit. Under cathodic protection, the reduction of oxygen induces an increase of the interfacial pH and then formation of Scale Deposit. The usual chronoamperometric analysis was completed by an in situ observation of the Scale Deposit. In natural water the biofilm development was studied by electrochemical method to determine the biofilm thickness and this analysis is completed by a direct observation through the electrode. A good correlation between the two techniques was found.
Sean P S Gulick - One of the best experts on this subject based on the ideXlab platform.
-
the cretaceous paleogene boundary Deposit in the gulf of mexico large Scale oceanic basin response to the chicxulub impact
Journal of Geophysical Research, 2016Co-Authors: Jason C Sanford, John W Snedden, Sean P S GulickAbstract:Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatan Peninsula, the gulf is the premier locale in which to study the near-field geologic effect of a bolide impact. We mapped a thick (decimeter- to hectometer-Scale) Deposit of carbonate debris at the Cretaceous-Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret Deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the Deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow-water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact Deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact-generated Deposition overwhelmed virtually all topography and Depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.
John W Snedden - One of the best experts on this subject based on the ideXlab platform.
-
the cretaceous paleogene boundary Deposit in the gulf of mexico large Scale oceanic basin response to the chicxulub impact
Journal of Geophysical Research, 2016Co-Authors: Jason C Sanford, John W Snedden, Sean P S GulickAbstract:Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatan Peninsula, the gulf is the premier locale in which to study the near-field geologic effect of a bolide impact. We mapped a thick (decimeter- to hectometer-Scale) Deposit of carbonate debris at the Cretaceous-Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret Deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the Deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow-water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact Deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact-generated Deposition overwhelmed virtually all topography and Depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.
O Devos - One of the best experts on this subject based on the ideXlab platform.
-
on the intrinsic coupling between constant phase element parameters α and q in electrochemical impedance spectroscopy
Electrochimica Acta, 2012Co-Authors: Pedro Cordobatorres, Bernard Tribollet, Thiago J Mesquita, O Devos, Virginie Roche, R P NogueiraAbstract:Abstract This paper presents experimental evidences of an intrinsic coupling between the α and Q parameters of constant phase elements (CPE) used in equivalent electrical circuits for EIS data fitting. Clear correlations have been found for two different experimental conditions, anodic dissolution and Scale Deposit, for which CPE behavior appears as the result of a time constant distribution originated from surface inhomogeneity. Results are in agreement with a coupling function that relates CPE parameters with interfacial quantities such as the ohmic and charge transfer resistances, and also with a characteristic interfacial capacitance whose meaning is addressed here. Although this relationship was initially derived from a theoretical model in which perfect CPE behavior was caused by a double-layer capacity distribution along the interface, it has been extensively used in the literature to estimate interface capacitance from CPE parameters in very different complex systems without any definitive evidence of it. However, its exportability to real systems can be explained from the fact that it can be deduced from simple and general arguments. In this paper we argue on these ideas in the basis of experimental evidences.
-
simultaneous eis and in situ microscope observation on a partially blocked electrode application to Scale electroDeposition
Electrochimica Acta, 2006Co-Authors: O Devos, C Gabrielli, Bernard TribolletAbstract:A novel technique allowed EIS and microscopical observation of the interface between electrode and solution to be coupled in situ. The electrochemical reduction of oxygen was investigated by using this device when the electrode surface was progressively covered by an insulating layer of Scale Deposit. It was shown that two time domains can be distinguished from the initial time of the experiment corresponding to a bare electrode up to a totally blocked surface. In the first part of the experiment, EIS showed one time constant which characterizes the charge transfer process of water reduction. When the percentage of coverage reached more than 80%, this latter electrochemical contribution to EIS was negligible and the reduction process of oxygen was highlighted by two time constants observed from impedance diagrams. The high frequency response characterized the charge transfer process and the low frequency loop identified the diffusion process of oxygen. An electrochemical model was proposed to explain the shape of the impedance spectra plotted with respect to the time of coverage. The good correlation between the experimental and the fitted model curves led to the change versus time of the different parameters of the equivalent circuit. It notably showed that the double layer capacity was directly proportional to the active surface measured by the microscope observation until the surface was totally covered, according to the expectations in the experimental conditions used here.
