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CN-121995469-A - Dynamic monitoring method for longitudinal development of oil layer based on time-lapse earthquake

CN121995469ACN 121995469 ACN121995469 ACN 121995469ACN-121995469-A

Abstract

The invention provides a time-lapse earthquake-based dynamic monitoring method for longitudinal development of an oil layer, which comprises the steps of 1 respectively explaining stratum slice control layers of an oil layer of a monitoring earthquake and a basic earthquake, 2 respectively solving amplitude differences of the monitoring earthquake and the basic earthquake on the whole oil layer, 3 respectively determining whether a proportional relationship exists between the whole amplitude differences of the oil layer and dynamic data, 4 respectively cutting a proper and equal number of stratum slices of the monitoring earthquake and the basic earthquake, 5 respectively solving amplitude or attribute differences before and after time-lapse on each slice of the obtained earthquake and the basic earthquake, and selecting a plurality of slice differences with the most obvious longitudinal capability of the monitoring oil layer, 6 respectively comparing the solved stratum slice differences out of phase, and monitoring the development differences of different parts of the longitudinal direction of the oil layer to guide the adjustment of a development scheme. The invention can adopt targeted technical measures to carry out development scheme adjustment, improves the longitudinal monitoring capability of time-lapse earthquake to the oil layer, and further improves the recovery ratio of the oil layer.

Inventors

  • LI HAITAO
  • NIU XUEMIN
  • RUI YONGJUN
  • SHANG XINMIN
  • DAI LEI
  • SHEN GUOQIANG
  • Wu Lukai
  • CHEN HONG
  • WANG GUIZHAI

Assignees

  • 中国石油化工股份有限公司
  • 中国石油化工股份有限公司胜利油田分公司

Dates

Publication Date
20260508
Application Date
20241101

Claims (14)

  1. 1. The time-lapse seismic based reservoir longitudinal development dynamic monitoring method is characterized by comprising the following steps of: step 1, respectively explaining stratum slice control layers of the monitoring earthquake and the basic earthquake oil layer; step 2, solving amplitude differences of the monitoring earthquake and the basic earthquake in the whole oil layer; step 3, determining whether the whole amplitude difference of the oil layer and the dynamic data have a direct proportion relation; Step 4, cutting proper stratum slices with the same number from the monitoring earthquake and the basic earthquake respectively; Step 5, respectively solving amplitude or attribute differences before and after time shift for each slice of the obtained earthquake and the basic earthquake, and selecting a plurality of slice differences with the most obvious longitudinal capability of monitoring an oil layer; And 6, comparing the obtained stratum slice differences and phases, monitoring development differences of different longitudinal parts of the oil layer, and guiding the development scheme to adjust.
  2. 2. The method of claim 1, wherein in step 1, the slice control layer of the reservoir of the monitoring earthquake and the base earthquake is a well-defined, easily-tracked reservoir top-bottom interface corresponding to the seismic reflection axis or an easily-tracked seismic reflection axis in the same deposition unit immediately adjacent to the reservoir top-bottom interface.
  3. 3. The method for dynamically monitoring longitudinal development of oil reservoirs based on time lapse earthquake according to claim 1, wherein in step 1, the method for automatically tracking and interpreting is used for interpreting peaks or troughs or zero points of the earthquake reflection axis corresponding to the control horizon by 1x1 grid horizon, so as to ensure consistency of control horizons of stratum slices before and after time lapse.
  4. 4. The method for dynamically monitoring longitudinal development of reservoir based on time lapse earthquake according to claim 1, wherein in step 2, the top-bottom control layer of the stratum slice of the monitoring earthquake and the basic earthquake reservoir explained in step 1 is used to extract the amplitude attribute or other time lapse sensitivity attribute of the monitoring earthquake and the basic earthquake reservoir respectively, and then the amplitude attribute or other sensitivity attribute difference is directly subtracted from the amplitude attribute or other sensitivity attribute of the basic earthquake whole reservoir.
  5. 5. The method for dynamically monitoring longitudinal development of oil reservoir based on time lapse earthquake according to claim 1, wherein in step 2, suitable sensitive attribute bodies of the base earthquake and the monitoring earthquake are extracted first, the base earthquake and the monitoring earthquake are extracted by using the control layer at the top and bottom of the stratum slice of the base earthquake and the monitoring earthquake oil reservoir, which are explained in step 1, respectively, and finally, the sensitive attribute of the monitoring earthquake integral oil reservoir and the sensitive attribute of the base earthquake integral oil reservoir are directly subtracted to obtain the sensitive attribute difference of the integral oil reservoir.
  6. 6. The method for dynamically monitoring longitudinal development of an oil reservoir based on time lapse earthquake as claimed in claim 1, wherein in step 3, the range of the difference of the whole earthquake amplitude attribute or other time lapse earthquake sensitive attribute of the oil reservoir section obtained in step 2 is compared with the dynamic data of the research well, and whether a direct proportional relationship exists between the range of the difference and the dynamic data of the single well is determined and verified.
  7. 7. The method for dynamically monitoring longitudinal development of reservoir based on time lapse earthquake as claimed in claim 1, wherein in step 4, the control horizon is used to cut stratum slices for the monitoring earthquake and the base earthquake respectively, the number of slices is enough to reflect the earthquake changes of different longitudinal parts of reservoir of all the research wells, each separated reservoir is cut for the reservoir with the interlayer, and the slices of the monitoring earthquake and the base earthquake are in one-to-one correspondence.
  8. 8. The method for dynamically monitoring longitudinal development of oil reservoirs based on time lapse earthquake as set forth in claim 7, wherein in step 4, in case of large difference of oil reservoir distribution among the research wells, proper number of time lapse front and back formation slices are needed to be cut out from the split wells respectively.
  9. 9. The method for dynamically monitoring longitudinal development of reservoir based on time lapse earthquake according to claim 1, wherein in step 5, the amplitude attribute or other time lapse sensitivity attribute is obtained along all stratum slices of the basic earthquake and the monitoring earthquake reservoir respectively, the monitored earthquake amplitude attribute or other time lapse sensitivity attribute of each stratum slice is directly subtracted from the basic earthquake difference or other time lapse sensitivity attribute to obtain the amplitude attribute or other time lapse sensitivity attribute difference of each stratum slice, the most obvious amplitude difference or other time lapse sensitivity attribute difference capable of monitoring the longitudinal condition of the reservoir is selected, or the earthquake stratum slices before and after the time lapse capable of monitoring the longitudinal distribution condition of the reservoir of a research target well region are selected, the earthquake amplitude or other time lapse sensitivity attribute difference is extracted from the selected stratum slices, and the earthquake amplitude attribute difference or other time lapse sensitivity attribute difference is subtracted.
  10. 10. The method for dynamically monitoring longitudinal development of oil reservoirs based on time lapse earthquake according to claim 1, wherein in step 5, sensitive attributes are extracted from base earthquake and monitoring earthquake respectively, a proper and equivalent number of stratum slices are cut from the monitoring earthquake attribute and the base earthquake sensitive attribute respectively by using control layers respectively, then slice sensitive attribute differences are obtained by directly subtracting the obtained monitoring earthquake and base earthquake sensitive attribute slices, and finally slice sensitive attribute differences which are most obvious and can monitor longitudinal conditions of the oil reservoirs are selected.
  11. 11. The method for dynamically monitoring the longitudinal development of the oil layer based on the time lapse earthquake according to claim 1, wherein in step 6, based on the study of step 5, the differences of the development conditions of different parts of the oil layer in the longitudinal direction are monitored by comparing and analyzing the differences of the earthquake amplitudes of different stratum slices or the differences of other time lapse earthquake sensitive attributes and combining with the dynamic data of the oil layer development, so as to guide the adjustment of the development scheme.
  12. 12. The method for dynamically monitoring longitudinal development of oil reservoirs based on time lapse earthquakes according to claim 11, wherein in step 6, the oil and gas movement ranges and movement directions around well points on different stratum slices are deduced according to the magnitude of the amplitude around the well points on different slices and the magnitude of the difference range of other time lapse earthquakes sensitive properties, and the longitudinal development difference of the oil reservoirs is clarified, so that the adjustment of a single well steam injection scheme is guided.
  13. 13. The method for dynamically monitoring the longitudinal development of the oil layer based on the time lapse earthquake as claimed in claim 11, wherein in step 6, the amplitude difference around the well points on different sections or the communication relation of other time lapse earthquake sensitive attributes is combined with other dynamic data, the difference of the longitudinal distribution condition of the inter-well interference in the oil layer is analyzed, and the longitudinal plugging and water plugging scheme in the inter-well oil layer is designed according to the difference.
  14. 14. The time-lapse-earthquake-based reservoir longitudinal development dynamic monitoring system is characterized in that the time-lapse-earthquake-based reservoir longitudinal development dynamic monitoring system adopts the time-lapse-earthquake-based reservoir longitudinal development dynamic monitoring method according to any one of claims 1 to 13 to perform earthquake reservoir longitudinal monitoring.

Description

Dynamic monitoring method for longitudinal development of oil layer based on time-lapse earthquake Technical Field The invention relates to the technical field of oil reservoir exploration and development, in particular to a dynamic monitoring method for longitudinal oil reservoir development based on time-lapse earthquake. Background Reservoir dynamic monitoring is measures and means adopted for knowing and mastering the seepage dynamics of fluid in a reservoir, the underground reservoir change conditions of a production well and various injection wells in the development and production process of the reservoir. Wherein the prediction of residual oil is a main technical goal of reservoir dynamic monitoring. The conventional main means for dynamic monitoring of the oil reservoir at present comprise (1) development of open hole well logging, (2) casing well logging, (3) development of test well, (4) analysis and test, and (5) interwell monitoring. The above techniques are mainly applied to the data in the well and between the wells, and are 'one hole' or 'first line' and have smaller monitoring range on oil reservoirs. The time-lapse earthquake is a relatively new oil reservoir dynamic monitoring technology, in theory, after the imaging results of the time-lapse earthquake are subtracted, the static properties (such as structure, lithology and the like) of the oil and gas reservoir can be effectively removed, so that the direct imaging of the dynamic fluid properties (fluid saturation, pressure, temperature and the like) of the oil and gas reservoir can be obtained, and the oil reservoir can be monitored in a large range. The time-lapse earthquake is applied to develop reservoir management, so that the three-dimensional characteristics of the oil and gas reservoir can be revealed, the time-lapse difference information of earthquake response can be fully utilized, the positions of residual oil can be identified through calibration of logging information and development information, and precious information is provided for optimizing development schemes and reducing dry wells. At present, the domestic time-lapse seismic technology is still in a deepened research stage. Under the current requirement of further improving the oil reservoir development precision, not only is the integral or most prominent change of the oil reservoir required to be monitored, but also the development and utilization conditions of different longitudinal parts of the oil reservoir can be monitored, so that a method for improving the longitudinal monitoring capability of the earthquake oil reservoir is required. The China patent application with the application number of CN202311585979.9 relates to a residual oil gas prediction method and a residual oil gas prediction system based on time difference interpretation, wherein the residual oil gas prediction method and the residual oil gas prediction system comprise the steps of selecting any two-period seismic data in time-lapse seismic data, performing seismic data conversion based on slope operation to obtain extremum domain data of the two-period seismic data, performing time-lapse seismic time difference interpretation based on extremum domain data of the two-period seismic data, and predicting residual oil gas based on time-lapse seismic time difference interpretation results. The invention innovatively develops the method for converting the time-lapse two-period seismic data into extremum volume data through slope, arctangent and difference operation, effectively highlights the detail characteristics of longitudinal and transverse changes of the seismic data, and can realize the fine interpretation of a target layer position by utilizing the extremum volume, thereby obtaining the time-lapse time difference attribute and breaking through the problem that the traditional post-stack seismic time difference attribute is difficult to obtain. In the chinese patent application of application number CN201010244645.1, a method is referred to for identifying whether time lapse seismic can be performed. The method comprises the steps of obtaining energy variation differences of seismic effective signals caused by oil reservoir parameter changes, obtaining noise levels in actual seismic data, and comparing the energy variation differences with the noise levels, wherein if the energy variation differences are larger than the noise levels, time-lapse seismic can be implemented. By comparing the simulated energy change with the result of the signal-to-noise ratio analysis, it can be seen that the energy change (13.3%) of the seismic effective signal caused by the reservoir parameter change such as pressure drop in the gas field in the embodiment is far higher than the noise level (2.9%) in the region. It is therefore believed that the field may now be performing time lapse earthquakes. In the chinese patent application of application number CN201010196389.3, a method for well placement by time la