Patent ID: 10545256

Abstract:
Apparatus (57, 58) for determining permittivity in a downhole location comprises a sensor (57) including an elongate conducting line (62) supported on or adjacent a first side of a dielectric substrate (61). The sensor (57) also includes at least one conducting ground element (26, 27) that is spaced from the conducting line (62), the conducting line (62) being capable of juxtaposition to a downhole borehole wall (12). The apparatus further includes connected respectively to spaced locations along the conducting line at least two terminals (31, 32; 63, 64) of a vector network analyser (57b) that is capable of detecting one or more signal reflection characteristics whereby when the sensor (57) is juxtaposed to a borehole wall (12) the vector network analyser (57b) generates one or more signals that are processable to indicate the relative permittivity of rock (39) in which the borehole is formed.