Unlock instant, AI-driven research and patent intelligence for your innovation.

Method and device for determining stratum wave travel time

A determination method, a technology of formation waves, applied in the direction of earthwork drilling, surveying, wellbore/well components, etc., can solve the problem of low accuracy and so on

Active Publication Date: 2021-03-12
CHINA NAT OFFSHORE OIL CORP +1
View PDF7 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In acoustic logging while drilling, the traditional method of calculating formation wave travel time using cable acoustic waves has the problem of low accuracy and is no longer applicable

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method and device for determining stratum wave travel time
  • Method and device for determining stratum wave travel time
  • Method and device for determining stratum wave travel time

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0051] An embodiment of the present disclosure provides a method for determining the travel time of a formation wave, which is measured by an acoustic logging tool while drilling. The scene where the sonic logging while drilling instrument used in the embodiment of the present disclosure performs measurement is as follows: figure 1 shown. The detection part of the acoustic logging while drilling tool goes deep into the well to be measured, and the detection part at least includes: an acoustic wave transmitter and N receivers (R1-RN).

[0052] A method for determining the travel time of formation waves, the process of which is as follows figure 2 shown, including,

[0053] Step 0, obtaining a depth-measured acoustic wave monopole data while drilling; the acoustic wave monopole data while drilling includes N original acoustic wave monopoles while drilling obtained in the depth measurement by N receivers of the acoustic logging tool while drilling polar waveform;

[0054] St...

Embodiment 2

[0099] The embodiment of the present disclosure also provides a method for determining formation wave travel time, which is applied to a sonic logging tool while drilling, and its process is as follows Figure 9 shown, including:

[0100] Step 901: Obtain a plurality of original acoustic monopole waveforms while drilling corresponding to the plurality of receivers measured by the acoustic logging tool while drilling at a set measurement depth, and determine according to the plurality of original acoustic monopole waveforms while drilling Array filter waveform;

[0101] Step 902, according to the array filter waveform, determine the compressional wave slowness and shear wave slowness of the formation wave;

[0102] Step 903, according to the compressional wave slowness of the formation wave, after performing superimposition processing on the array filter waveform, a measured array waveform is formed;

[0103] Step 904, calculate the theoretical array waveform according to the...

Embodiment 3

[0140] The embodiment of the present disclosure also provides a method for determining formation wave travel time, which is applied to a sonic logging tool while drilling, and its process is as follows Figure 10 shown, including:

[0141] Step 101, within the depth range of the well to be measured, select a preset number of measurement depths, respectively execute the above-mentioned formation wave traveltime determination method at each measurement depth, and determine the formation compressional wave traveltime corresponding to the measurement depth;

[0142] Step 102: Determine the formation travel time curve of the well to be measured according to the travel time of the formation compressional wave corresponding to all the measurement depths within the depth range of the well to be measured.

[0143] In some exemplary embodiments, the preset number of measurement depths (depth positions, depth points) are evenly distributed within the depth range of the well to be measure...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method and a device for determining formation wave travel time applied to a while-drilling acoustic logging instrument. The method comprises the following steps: acquiring aplurality of measured original while-drilling sound wave monopole waveforms, and determining an array filtering waveform; determining the longitudinal wave slowness and the transverse wave slowness ofthe stratum wave according to the array filtering waveform; according to the longitudinal wave slowness of the stratum wave, performing superposition processing on the array filtering waveform to form an actual measurement array waveform; calculating a theoretical array waveform according to the array filtering waveform, the longitudinal wave slowness, the transverse wave slowness and set calculation parameters; judging whether convergence conditions are met or not according to the actual measurement array waveform and the theoretical array waveform, and if yes, extracting stratum longitudinal wave travel time according to the theoretical array waveform; and if not, modifying the stratum density and / or the borehole radius in the calculation parameters, recalculating the theoretical arraywaveform, and judging whether a convergence condition is met or not.

Description

technical field [0001] The present disclosure relates to but not limited to the field of stratum evaluation, and in particular relates to a method and device for determining the travel time of strata. Background technique [0002] In the field of stratum evaluation, it is of great significance to extract the travel time of formation waves from the acoustic wave signals of the acoustic logging array. The properties of the pore fluid; the travel time of the formation wave can also be used for the imaging of the radial velocity profile of the formation, so as to evaluate the brittleness of the rock and guide the fracturing operation of the reservoir. [0003] In wireline acoustic logging, it is relatively easy to calculate the travel time of formation waves, and the energy ratio method or the velocity of formation waves is used to calculate the travel time. In acoustic logging while drilling, the traditional method of calculating formation wave travel time using cable acoustic...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G06F30/20E21B47/14E21B49/00
CPCG06F30/20E21B47/14E21B49/00
Inventor 孙志峰仇傲刘西恩陈洪海孙小芳王春艳
Owner CHINA NAT OFFSHORE OIL CORP