Influencing Factors of P/S Wave Velocity Ratio and Gas-Water Identification in Tight Sand Reservoir
Velocity ratio of P/S wave plays an important role in gas-bearing property evaluation of the tight sand. With the emergence of water-producing wells in the study area, the first layer of Jurassic Shaximiao formation of F area, the property of fluid has changed from gas to gas-water, and there are so...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | zho |
| Published: |
Editorial Office of Well Logging Technology
2023-10-01
|
| Series: | Cejing jishu |
| Subjects: | |
| Online Access: | https://www.cnpcwlt.com/#/digest?ArticleID=5527 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Velocity ratio of P/S wave plays an important role in gas-bearing property evaluation of the tight sand. With the emergence of water-producing wells in the study area, the first layer of Jurassic Shaximiao formation of F area, the property of fluid has changed from gas to gas-water, and there are some water zones of high-resistance, which leads to the low coincidence rate of both the basic value method of P/S wave velocity ratio and the resistivity method in judging gas-bearing property. Through numerical simulation and P-wave and S-wave experiments of the cores in formation conditions, the deficiency of the single P/S wave velocity ratio in gas-water identification is discussed, in other words, it is affected by the coupling of lithology, physical properties and saturation. Based on the experimental data, a saturation estimation model of the inversion of fluid bulk modulus based on Gassmann equation is also given. This model has a certain effect in the identification of the water zones of high-resistance in tight sand, and as a non-electrical method it shows the advantages of identifying the fluid property of reservoir with the attribute of difficult resistivity. |
|---|---|
| ISSN: | 1004-1338 |