Patents by Inventor Martin D. Hurlimann

Martin D. Hurlimann has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6133735
    Abstract: A technique is provided for determining a nuclear magnetic resonance characteristic of formations surrounding an earth borehole, including the following steps: providing a logging device that is moveable through the borehole; providing, on the logging device, first and second coils having respective axes that are generally orthogonal; producing, at the logging device, a prepolarizing signal; applying pulse sequence signals to the first and second coils, the pulse sequence signals implementing repeated refocusing of spins in the formations by both adiabatic and non-adiabatic reorienting of the spins to form spin echoes; and detecting, at the logging device, the spin echoes from the formations, the spin echoes being indicative of the nuclear magnetic resonance characteristic of the formations.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: October 17, 2000
    Assignee: Schlumberger Technology Corporation
    Inventors: Martin D. Hurlimann, Yi-Quao Song, Seungoh Ryu, Pabitra N. Sen
  • Patent number: 5680043
    Abstract: An NMR pulse sequence technique for use in the borehole environment is provided which uses CPMG pulses according to?W.sub.i -90-(t.sub.cp -180-t.sub.cp -echo).sub.j !.sub.iwhere j is the index of the CPMG echoes gathered, i is the index of the wait times in the pulse sequence, W.sub.i are the varying wait times before the CPMG pulses, and tcp is the Carr-Purcell spacing. Measurements are made of the signals induced in the formation as a result of the magnetic fields to find the spin-echo relaxation time T1. Using T1, the gas effect on formation parameters may be derived. Also, gas saturation and gas chemical composition can be derived. In addition, the diffusion coefficient of gas under reservoir conditions can be more than ten times larger than that of water, making the T.sub.2 relaxation time of gas more sensitive to static magnetic field gradients. In formations where gas occupies pores larger than about 10 .mu.m, this T.sub.2 effect (effect of diffusion on the measured T.sub.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: October 21, 1997
    Assignee: Schlumberger Technology Corporation
    Inventors: Martin D. Hurlimann, Robert L. Kleinberg