The formation resistivity factor evaluation of brine-filled reservoir rock is an essential part of electrical resistivity log interpretation in petroleum exploration. Empirical relations such as Archie’s law are widely employed to model the relationship between the formation resistivity factor and porosity. Historically, the Archie cementation exponent has been obtained from experimental labora...

It is known that the three important parameters: resistivity, capillary pressure, and relative permeability, are all a function of fluid saturation in a porous medium. This implies that there may be a correlation among the three parameters. There have been many papers on the approach to inferring relative permeability from capillary pressure data. However the literature on the interrelationship...

a Laboratoire d’Étude et Modélisation des Environnements Littoraux (Lemel), Université de Bretagne Sud, Centre Yves Coppens, Campus de Tohannic, F-56000, Vannes. b Laboratoire de Statistiques Appliquées de BREtagne Sud (Sabres), Université de Bretagne Sud, Centre Yves Coppens, Campus de Tohannic, F-56000, Vannes. c Laboratoire de Mathématiques et Applications des Mathématiques (LMAM) , Universi...

Since the last few decades, electrical methods have been widely used in geophysical surveying to obtain high-resolution information about subsurface conditions. Resistivity is an important parameter in judging the ground properties, especially detecting buried objects of anomalous conductivity. Electrical DC resistivity sounding is the commonly used technique to obtain the apparent 2-D resistiv...

Phase change of pore fluid (boiling/condensing) in rock cores under conditions representative of geothermal reservoirs results in alterations of the electrical resistivity of the samples. In fractured samples, phase change can result in resistivity changes that are more than an order of magnitude greater than those measured in intact samples. These results suggest that electrical resistivity mo...

Knowing and controlling the resistivity of an individual nanowire (NW) is crucial for the production of new sensors and devices. For ZnO NWs this is poorly understood; a 10(8) variation in resistivity has previously been reported, making the production of reproducible devices almost impossible. Here, we provide accurate resistivity measurements of individual NWs, using a four-probe scanning tun...

OBJECTIVE We characterized electrode stability over twelve weeks of impedance and neural recording data from four chronically-implanted Utah arrays in two rhesus macaques, and investigated the effects of glial scarring and interface interactions at the electrode recording site on signal quality using a computational model. APPROACH A finite-element model of a Utah array microelectrode in neur...