Inventor

ROSTHAL RICHARD A

US36 patents

⚠️ This page may combine multiple inventors who share the name “ROSTHAL RICHARD A”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

ROSTHAL RICHARD A

SCHLUMBERGER TECHNOLOGY CORP

Shielding method and apparatus using transverse slots

Method and apparatus for evaluating the resistivity of formations with high dip angles or high-contrast thin layers

Method and apparatus for directional well logging with a shield having sloped slots

Dipmeter apparatus and method using transducer array having longitudinally spaced transducers

Directional electromagnetic measurements insensitive to dip and anisotropy

Method and apparatus for cancellation of borehole effects due to a tilted or transverse magnetic dipole

Shielding method and apparatus for selective attenuation of an electromagnetic energy field component

Method and apparatus for determining horizontal conductivity and vertical conductivity of earth formations

Induction logging method and apparatus including means for combining on-phase and quadrature components of signals received at varying frequencies and including use of multiple receiver means associated with a single transmitter

Method and apparatus for controlling the effect of contact impedance on a galvanic tool in a logging-while-drilling application

Apparatus and method for determining the resistivity of earth formations

Antenna structures for electromagnetic well logging tools

Method and apparatus for cancellation of borehole effects due to a tilted or transverse magnetic dipole

Borehole current correction methods and apparatus

Coil shielding method for selective attenuation of an electromagnetic energy field component

Shielding apparatus for selective attenuation of an electromagnetic energy field component

Induction coil impedance modeling using equivalent circuit parameters

Anti-symmetrized electromagnetic measurements

Method and apparatus for determining the presence and orientation of a fraction in an earth formation

Shielding method and apparatus using flexible strip

Apparatus and method for determining the resitivity of underground formations surrounding a borehole

Determining correction factors representing effects of different portions of a lining structure

Electromagnetic logging tool calibration system

Apparatus and methods for determining isotropic and anisotropic formation resistivity in the presence of invasion

Apparatus and methods for reducing borehole current effects

Borehole current correction for tilted or transverse magnetic dipoles on conductive supports

Passive, active and semi-active cancellation of borehole effects for well logging

Apparatus and methods for determining isotropic and anisotropic formation resistivity in the presence of invasion

Method and apparatus for removal of the double indication of defects in remote eddy current inspection of pipes

ZHANG HONG

Surface to borehole electromagnetic surveying using metallic well casings as electrodes

Electromagnetic logging between a cased borehole and surface

Detecting electrical current in a magnetic structure

LEGENDRE EMMANUEL

Method and apparatus for removal of the double indication of defects in remote eddy current inspection of pipes

ROSTHAL RICHARD A

Correction factors for electromagnetic measurements made through conductive material

GAO GUOZHONG

Attenuation of electromagnetic signals passing through conductive material

MORRISON FRANK

Characterizing at least one property of a liner that lines a well