Systems and methods for high-resolution travel time and move-out velocity estimation using downhole linear receiver arrays
AssigneeHalliburton Energy Services, Inc.
InventorKristoffer Thomas Walker
Life of this patent
Estimating the term…
Abstract
A method for borehole measurements may comprise receiving one or more signals from a linear receiver array, computing an arctan of a Hilbert Transform, isolating a first arriving energy, selecting a reference instantaneous phase on a reference receiver, finding the reference instantaneous phase for the linear receiver array, computing a relative travel time shift, combining a reference pick time with a relative time, and determining a travel time. A system for borehole measurements comprise a conveyance, a bottom hole assembly attached to the conveyance, a linear receiver array, wherein the linear receiver array is disposed on the bottom hole assembly, and a computer system connected to the linear receiver array.
Claims20
A method for borehole measurements, comprising:
- receiving one or more signals from a linear receiver array;
- computing an arctan of a Hilbert Transform;
- isolating a first arriving energy;
- selecting a reference instantaneous phase on a reference receiver;
- finding the reference instantaneous phase for the linear receiver array;
- computing a relative travel time shift;
- combining a reference pick time with a relative time;
- and
- determining a travel time.
A method for borehole measurements, comprising:
- receiving one or more signals from a linear receiver array;
- isolating a first arriving energy;
- assigning a reference receiver as a matched filter;
- performing a cross-correlate filter with one or more receivers;
- computing a relative travel time shift;
- aligning a first arrival energy;
- assigning an average of aligned first arrival energy as the matched filter;
- evaluating a convergence;
- combining a reference pick time with a relative time;
- and
- determining a travel time.
A system for borehole measurements comprising:
- a conveyance;
- a bottom hole assembly attached to the conveyance;
- a linear receiver array, wherein the linear receiver array is disposed on the bottom hole assembly;
- and
- a computer system connected to the linear receiver array and configured to:
- compute an arctan of a Hilbert Transform;
- isolate a first arriving energy;
- select a reference instantaneous phase on a reference receiver;
- find the reference instantaneous phase for the linear receiver array;
- compute a relative travel time shift;
- combine a reference pick time with a relative time;
- and
- determine a travel time.
Dependencies are inferred from the claim text.